A pharmaceutical composition for treating bacterial skin infections

Abstract

The present invention discloses a pharmaceutical composition for treating bacterial skin infections. By combining fluoroquinolone antibiotics and / or glycopeptide antibiotics with indocyanine green, the present invention synergistically enhances the antibacterial effect of antibiotics, reduces the dosage of antibiotics, and thus reduces the side effects caused by overuse of antibiotics. The present invention combines the respective advantages of phototherapy antibacterial and antibiotic antibacterial, makes up for the deficiencies of single antibacterial therapy, reduces the dosage of antibiotics required to achieve the same antibacterial effect through phototherapy antibacterial, and at the same time maintains and enhances the effect of phototherapy antibacterial through antibiotics to improve the transient problem of phototherapy antibacterial relying on laser irradiation.

Description

Technical Field

[0001] The present invention belongs to the technical field of medicine, and particularly relates to a pharmaceutical composition for treating bacterial skin infections. Background Art

[0002] The skin is the first natural barrier between the human body and nature. It can protect the internal tissues and organs of the body from external attacks, prevent the loss of body fluids inside the human body, and also has the functions of sensing and regulating body temperature. Although many bacteria come into contact with or parasitize on the skin, they usually do not cause infections under normal circumstances. Bacterial skin infections occur when bacteria enter through hair follicles or through small skin breaks caused by scratches, stabs, surgeries, burns, sunburns, animal or insect bites, wounds, and pre-existing skin lesions. The infected area can range from a small spot to the entire skin surface. People may develop bacterial skin infections after participating in various activities, such as gardening in contaminated soil, or swimming in contaminated ponds, lakes, or the ocean.

[0003] At present, the treatment of bacterial skin infections in clinical practice still mainly relies on the use of antibiotics. Fluoroquinolone antibiotics are a widely used class of antibiotics in clinical practice. Their structural characteristics are that on the basis of the basic structure of quinolone, a fluorine atom is added at the C6 position and a basic piperazine group is added at the C7 position. This class of compounds has the characteristics of broad antibacterial spectrum, strong antibacterial effect, high bioavailability, good tissue permeability, etc. The bactericidal concentration is 2-4 times the minimum inhibitory concentration (MIC). Representative compounds include sparfloxacin, norfloxacin, ciprofloxacin, levofloxacin, gatifloxacin, moxifloxacin, lomefloxacin, grepafloxacin, fleroxacin, clinafloxacin, etc. Research shows that this class of compounds can act on DNA topoisomerase to prevent processes such as DNA replication and transcription, thereby causing bacterial death. Another class of antibiotics widely used in clinical practice is glycopeptide antibiotics, which share a highly modified heptapeptide backbone in structure and can interfere with cell wall synthesis by inhibiting the formation of phospholipids and polypeptides in the bacterial cell wall, thereby inhibiting the growth and reproduction of bacteria. Due to the unique chemical structure and mechanism of action of such antibiotics, there is no cross-resistance phenomenon with other antibacterial drugs. Representative compounds include vancomycin, teicoplanin, oritavancin, etc. However, with the increasingly serious problems such as drug resistance and side effects caused by the abuse of antibiotics, and the biofilm formed after bacteria invade the body and colonize further enhancing the drug resistance of bacteria, it is difficult to cope with the severe challenge of increasingly serious bacterial drug resistance in the future by relying solely on antibiotics. Moreover, the overuse of antibiotics will also cause side effects such as flora imbalance and immune function decline.

[0004] Although new antibiotics are still being actively researched and developed, due to the complex and expensive research process and the risk of further inducing bacterial mutations and exacerbating the variation and evolution of multi-drug resistant bacteria after their application, the road to developing new drugs has been greatly hindered. Summary of the Invention

[0005] The purpose of the present invention is to provide a pharmaceutical composition for treating bacterial skin infections.

[0006] To achieve the above purpose, the present invention adopts the following technical solutions:

[0007] Use of the combination of fluoroquinolone antibiotics and / or glycopeptide antibiotics and indocyanine green in the preparation of a drug for treating bacterial skin infections.

[0008] Further, the fluoroquinolone antibiotic is sparfloxacin, norfloxacin, ciprofloxacin, levofloxacin, gatifloxacin, moxifloxacin, lomefloxacin, grepafloxacin, fleroxacin or clinafloxacin; the glycopeptide antibiotic is vancomycin, teicoplanin or oritavancin.

[0009] Furthermore, the dosage ratio w:w of the fluoroquinolone antibiotic to indocyanine green is 1:1 to 20; the dosage ratio w:w of the glycopeptide antibiotic to indocyanine green is 1 to 10:1; the dosage ratio w:w:w of the fluoroquinolone antibiotic, glycopeptide antibiotic and the phototherapeutic agent indocyanine green is 1:1 to 40:1 to 8.

[0010] A therapeutic drug for bacterial skin infections, comprising: a fluoroquinolone antibiotic and / or a glycopeptide antibiotic, indocyanine green, and a pharmaceutically acceptable carrier and / or excipient;

[0011] The dosage ratio w:w of the fluoroquinolone antibiotic to indocyanine green is 1:1 to 20;

[0012] The dosage ratio w:w of the glycopeptide antibiotic to indocyanine green is 1 to 10:1;

[0013] The dosage ratio w:w:w of the fluoroquinolone antibiotic, glycopeptide antibiotic and the phototherapeutic agent indocyanine green is 1:1 to 40:1 to 8.

[0014] Further, the fluoroquinolone antibiotic is sparfloxacin, norfloxacin, ciprofloxacin, levofloxacin, gatifloxacin, moxifloxacin, lomefloxacin, grepafloxacin, fleroxacin or clinafloxacin; the glycopeptide antibiotic is vancomycin, teicoplanin or oritavancin.

[0015] Further, the active ingredient of the therapeutic drug for bacterial skin infections is a composition of a fluoroquinolone antibiotic and / or a glycopeptide antibiotic and indocyanine green.

[0016] Further, the active ingredient of the therapeutic drug for bacterial skin infections is a self-assembled nanoparticle made of a fluoroquinolone antibiotic and / or a glycopeptide antibiotic and indocyanine green. In one embodiment of the present invention, the preparation method of the self-assembled nanoparticle is: dissolving the fluoroquinolone antibiotic and / or the glycopeptide antibiotic in a solvent, and then adding an aqueous solution of indocyanine green, and preparing the self-assembled nanoparticle after stirring.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] (1) In the present invention, the composition and / or self-assembled nanoparticles of fluoroquinolone antibiotics and the phototherapeutic agent indocyanine green, the composition and / or self-assembled nanoparticles of glycopeptide antibiotics and the phototherapeutic agent indocyanine green, and the composition and / or self-assembled nanoparticles of fluoroquinolone antibiotics, glycopeptide antibiotics and the phototherapeutic agent indocyanine green can not only produce a significant bactericidal effect, but also significantly reduce the dosage of antibiotics required to produce the same bactericidal effect, reducing the risk of bacteria developing drug resistance. Therefore, the combined application of two or three of them has an excellent synergistic antibacterial effect and can provide a new combination treatment strategy for the clinical treatment of bacterial skin infections.

[0019] (2) In the present invention, the composition and / or self-assembled nanoparticles of fluoroquinolone antibiotics and the phototherapeutic agent indocyanine green, the composition and / or self-assembled nanoparticles of glycopeptide antibiotics and the phototherapeutic agent indocyanine green, and the composition and / or self-assembled nanoparticles of fluoroquinolone antibiotics, glycopeptide antibiotics and the phototherapeutic agent indocyanine green can enhance the sensitivity of bacteria to antibiotics through phototherapy, thereby further reducing the risk of bacteria developing drug resistance.

[0020] (3) The clinical effect of treating bacterial infections with fluoroquinolone antibiotics or glycopeptide antibiotics alone depends on a high dose of antibiotics and requires continuous administration, which is likely to cause side effects such as flora imbalance and decreased immune function. In the present invention, the photodynamic antibacterial therapy mediated by the phototherapeutic agent indocyanine green can synergistically enhance the antibacterial effect of antibiotics and reduce the dosage of antibiotics, thereby reducing the side effects caused by overuse of antibiotics.

[0021] (4) Compared with the traditional use of antibiotics for antibacterial treatment, the greatest advantage of photodynamic antibacterial treatment is that it does not produce bacterial drug resistance. Indocyanine green, a phototherapeutic agent, is unstable in aqueous solution, sensitive to both light and water, which reduces its photodynamic effect, and the photodynamic antibacterial effect it mediates must rely on laser irradiation. The present invention combines the respective advantages of photodynamic antibacterial treatment and antibiotic antibacterial treatment to make up for the deficiencies of single antibacterial therapies. It reduces the dosage of antibiotics required to achieve the same antibacterial effect through photodynamic antibacterial treatment, and at the same time uses antibiotics to maintain and enhance the photodynamic antibacterial effect to improve the transient problem of photodynamic antibacterial treatment relying on laser irradiation. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Results of the bacterial survival rate of Staphylococcus aureus in Example 1 after treatment with different concentrations of sparfloxacin (SPX), different concentrations of the composition of sparfloxacin and indocyanine green (SPX+ICG), and different concentrations of self-assembled nanoparticles of sparfloxacin and indocyanine green (SPX-ICG).

[0023] Figure 2Results of bacterial survival rates of Escherichia coli after treatment with different concentrations of sparfloxacin (SPX), different concentrations of the combination of sparfloxacin and indocyanine green (SPX+ICG), and different concentrations of self-assembled nanoparticles of sparfloxacin and indocyanine green (SPX-ICG) in Example 1. Detailed implementation manners

[0024] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, but should not be construed as a limitation of the present invention. Without departing from the spirit and essence of the present invention, any modification or replacement made to the methods, steps or conditions of the present invention shall fall within the scope of the present invention. The experimental methods without specific conditions and the reagents without specific formulations described in the embodiments are all in accordance with the conventional conditions in the art.

[0025] The bacterial models used in the present invention are selected from common bacteria causing bacterial skin infections, including Gram-positive bacteria (Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli). The specific culture process is as follows:

[0026] Use an inoculation loop to pick up the bacterial liquid from the bacterial preservation solution, and draw four areas on the blood plate by the streak plate method, and statically culture at 37°C for 48 h to obtain single colonies. Use an inoculation loop to pick up a single colony and place it in a broth medium, and shake and culture at 37°C until the bacteria reach the logarithmic growth phase. This is the bacterial suspension used to evaluate the antibacterial effect of the above drug composition.

[0027] Criteria for judging that the bacteria enter the logarithmic growth phase: Inoculate a single bacterial colony into a conical flask containing a broth medium, shake and culture at 37°C, take samples at regular intervals, measure the optical density value (OD value) with a spectrophotometer to characterize the bacterial concentration, and plot the obtained results against the corresponding culture time to obtain the growth curve of the bacteria. When the slope of the bacterial growth curve is the largest, it is considered that the bacteria are in the logarithmic growth phase.

[0028] Example 1

[0029] Evaluation of the antibacterial properties of the combination of sparfloxacin (SPX) and indocyanine green (ICG) against Staphylococcus aureus and Escherichia coli

[0030] Preparation of self-assembled nanoparticles with a mass ratio of sparfloxacin to indocyanine green of 1.25:1: Weigh 1 mg of sparfloxacin and dissolve it in 1 mL of dimethyl sulfoxide to prepare a dimethyl sulfoxide solution of sparfloxacin. Weigh 0.5 mg of indocyanine green and dissolve it in 2 mL of water to prepare an aqueous solution of indocyanine green. Take 0.5 mL of the dimethyl sulfoxide solution of sparfloxacin and slowly add it dropwise to 1.6 mL of the aqueous solution of indocyanine green. After the addition is completed, stir for 2 h. Dialyze for 4 h using a dialysis bag (MWC = 3500) and sonicate for 10 min to obtain self-assembled nanoparticles with a mass ratio of sparfloxacin to indocyanine green of 1.25:1.

[0031] Preparation of self-assembled nanoparticles with a mass ratio of sparfloxacin to indocyanine green of 2.5:1: According to the preparation method of self-assembled nanoparticles with a mass ratio of sparfloxacin to indocyanine green of 1.25:1, replace "weigh 1 mg of sparfloxacin" with "weigh 2 mg of sparfloxacin", and self-assembled nanoparticles with a mass ratio of sparfloxacin to indocyanine green of 2.5:1 can be obtained.

[0032] Preparation of self-assembled nanoparticles with a mass ratio of sparfloxacin to indocyanine green of 3.75:1: According to the preparation method of self-assembled nanoparticles with a mass ratio of sparfloxacin to indocyanine green of 1.25:1, replace "weigh 1 mg of sparfloxacin" with "weigh 3 mg of sparfloxacin", and self-assembled nanoparticles with a mass ratio of sparfloxacin to indocyanine green of 3.75:1 can be obtained.

[0033] The particle sizes of the self-assembled nanoparticles prepared from sparfloxacin and indocyanine green with the above different mass ratios were measured by a Brookhaven nanometer particle size analyzer (Brookhaven Instruments Corporation, USA), and the results are shown in Table 1.

[0034] Table 1 Particle size characterization of self-assembled nanoparticles prepared from sparfloxacin and indocyanine green with different mass ratios

[0035]

[0036] As can be seen from the above table, the particle size of the self-assembled nanoparticles with a mass ratio of sparfloxacin to indocyanine green of 2.5:1 is less than 200 nm, and the PDI is less than 0.2, which is the best mass ratio among the self-assembled nanoparticles prepared using the above three mass ratios. Subsequently, the self-assembled nanoparticles prepared with a mass ratio of sparfloxacin to indocyanine green of 2.5:1 were used for antibacterial performance evaluation.

[0037] The ratio of the two in the self-assembled nanoparticles prepared with a mass ratio of sparfloxacin to indocyanine green of 2.5:1 was detected by ultraviolet spectrophotometry. Standard solutions with a series of concentrations of sparfloxacin and indocyanine green were prepared respectively, and the solvent was dimethyl sulfoxide. The absorbances of the standard solutions with their respective series of concentrations were detected at the ultraviolet maximum absorption wavelengths of sparfloxacin and indocyanine green, and a concentration-absorbance standard curve was plotted. Take 0.2 mL of the sparfloxacin and indocyanine green self-assembled nanoparticle solution, add 6.8 mL of dimethyl sulfoxide, measure its absorbance at the ultraviolet maximum absorption wavelengths of sparfloxacin and indocyanine green, substitute it into the standard curve, and calculate that the ratio (w:w) of sparfloxacin to indocyanine green in the self-assembled nanoparticles is 1:4.

[0038] The antibacterial properties of self-assembled nanoparticles of sparfloxacin and indocyanine green against Staphylococcus aureus and Escherichia coli were investigated by the broth microdilution method. For the experimental wells, 50 μL of serially two-fold diluted solutions of self-assembled nanoparticles of sparfloxacin and indocyanine green were added to wells 1 to 10 in a row of a 96-well plate, and then 50 μL of a bacterial suspension with a bacterial concentration of 1×10 6 CFU / mL prepared by further diluting using the above-mentioned bacterial culture method was added. For the control wells, 50 μL of serially two-fold diluted solutions of self-assembled nanoparticles of sparfloxacin and indocyanine green were added to wells 1 to 10 in another row, and then 50 μL of broth medium was added. For the growth control wells, 50 μL of broth medium and 50 μL of the aforementioned bacterial suspension were added to well 11 in each row. For the sterile control wells, 100 μL of broth medium was added to well 12 in each row. Based on the sparfloxacin concentration measurement, for Staphylococcus aureus, the SPX concentrations in wells 1 to 10 were 0.0025, 0.005, 0.01, 0.02, 0.04, 0.08, 0.16, 0.32, 0.64, 1.28 μg / mL respectively, and for Escherichia coli, the SPX concentrations in wells 1 to 10 were 0.000625, 0.00125, 0.0025, 0.005, 0.01, 0.02, 0.04, 0.08, 0.16, 0.32 μg / mL respectively. The bacterial concentration in wells 1 to 11 was 5×10 5 CFU / mL. After incubating in the dark at 37 °C for 30 min, for the experimental wells and the control wells, 808 nm laser with an illumination intensity of 1.5 W / cm 2 was used to irradiate for 90 s. The above 96-well plate was placed in static culture at 37 °C for 20 h. The absorbance of each well was measured at 620 nm using a microplate reader, and the bacterial survival rate was calculated according to formula (1). With the sparfloxacin concentration as the abscissa and the bacterial survival rate as the ordinate, a graph was plotted, and the minimal inhibitory concentration (MIC) of self-assembled nanoparticles of sparfloxacin and indocyanine green was calculated using GraphPad.

[0039]

[0040] In the formula, OD1 = absorbance of the experimental well, OD2 = absorbance of the control well, OD3 = absorbance of the growth control well, OD4 = absorbance of the sterile control well.

[0041] The antibacterial properties of the sparfloxacin and indocyanine green composition against Staphylococcus aureus and Escherichia coli were investigated using the above method. Replace the "sparfloxacin and indocyanine green self-assembled nanoparticle solution" with the "sparfloxacin and indocyanine green composition solution". Among them, weigh 0.2 mg and 0.4 mg, 0.2 mg and 0.8 mg, 0.2 mg and 1.6 mg of sparfloxacin and indocyanine green respectively, and add 40 mL of water to completely dissolve them to obtain sparfloxacin and indocyanine green composition solutions with mass ratios of 1:2, 1:4 and 1:8 respectively.

[0042] The antibacterial properties of sparfloxacin against Staphylococcus aureus and Escherichia coli were investigated using the above method. Replace the "sparfloxacin and indocyanine green self-assembled nanoparticle solution" with the "sparfloxacin solution", and cancel the "After incubating in the dark at 37 °C for 30 min, irradiate the experimental wells and control wells with an 808 nm laser with a light intensity of 1.5 W / cm 2 for 90 s".

[0043] As Figure 1It can be seen that for Staphylococcus aureus, when the concentration of sparfloxacin is 0.04 μg / mL, the bacterial survival rates of the self-assembled nanoparticles of sparfloxacin and indocyanine green (w:w = 1:4, P < 0.01) and the composition of sparfloxacin and indocyanine green (w:w = 1:2, P < 0.05; w:w = 1:4, P < 0.01; w:w = 1:8, P < 0.01) are significantly lower than those of the sparfloxacin group, indicating that the antibacterial properties of the self-assembled nanoparticles of sparfloxacin and indocyanine green and the composition of sparfloxacin and indocyanine green are significantly stronger than those of sparfloxacin, suggesting that both the self-assembled nanoparticles of sparfloxacin and indocyanine green and the composition of sparfloxacin and indocyanine green can significantly reduce the dosage of sparfloxacin required to achieve the same bactericidal effect. At the same time, when the concentration of sparfloxacin is 0.04 μg / mL, for sparfloxacin and indocyanine green with the same mass ratio (w:w = 1:4), the bacterial survival rate of the nanoparticle group is significantly lower than that of the physical mixture group (P < 0.05), indicating that the antibacterial property of the self-assembled nanoparticles is significantly stronger than that of the composition, probably because bacteria are more likely to uptake the nanoparticles. In addition, the smaller the MIC value of an antibiotic, the stronger the sensitivity of bacteria to the antibiotic. For Staphylococcus aureus, the MIC of sparfloxacin is 0.08084 μg / mL, and the MICs of the composition of sparfloxacin and indocyanine green (w:w = 1:2, w:w = 1:4, w:w = 1:8) are 0.06383 μg / mL, 0.04672 μg / mL, and 0.02598 μg / mL respectively, and the MIC of the self-assembled nanoparticles of sparfloxacin and indocyanine green (w:w = 1:4) is 0.03651 μg / mL, indicating that Staphylococcus aureus is more sensitive to the composition of sparfloxacin and indocyanine green or the self-assembled nanoparticles than to sparfloxacin, suggesting that the composition of sparfloxacin and indocyanine green or the self-assembled nanoparticles can enhance the sensitivity of bacteria to sparfloxacin through phototherapy.

[0044] As Figure 2It can be seen that for Escherichia coli, when the concentration of sparfloxacin is 0.01 μg / mL, the bacterial survival rates of the self-assembled nanoparticles of sparfloxacin and indocyanine green (w:w = 1:4, P < 0.01) and the composition group of sparfloxacin and indocyanine green (1:4, P < 0.01; 1:8, P < 0.01) are significantly lower than those of the sparfloxacin group, indicating that both the self-assembled nanoparticles of sparfloxacin-indocyanine green and the composition of sparfloxacin and indocyanine green have significantly stronger antibacterial properties than sparfloxacin, suggesting that both the self-assembled nanoparticles of sparfloxacin and indocyanine green and the composition of sparfloxacin and indocyanine green can significantly reduce the dosage of sparfloxacin required to produce the same bactericidal effect. At the same time, when the concentration of sparfloxacin is 0.01 μg / mL, for the same mass ratio (w:w = 1:4) of sparfloxacin and indocyanine green, the bacterial survival rate of the nanoparticle group is significantly lower than that of the physical mixture group (P < 0.01), indicating that the antibacterial property of the self-assembled nanoparticles is significantly stronger than that of the composition, probably because bacteria are more likely to uptake the nanoparticles. In addition, the smaller the MIC value of an antibiotic, the stronger the sensitivity of bacteria to the antibiotic. For Escherichia coli, the MIC of sparfloxacin is 0.01159 μg / mL, and the MICs of the composition of sparfloxacin and indocyanine green (w:w = 1:2, w:w = 1:4, w:w = 1:8) are 0.009738 μg / mL, 0.007180 μg / mL, and 0.004887 μg / mL respectively, and the MIC of the self-assembled nanoparticles of sparfloxacin and indocyanine green (w:w = 1:4) is 0.005856 μg / mL, indicating that Escherichia coli is more sensitive to the composition of sparfloxacin and indocyanine green or the self-assembled nanoparticles than to sparfloxacin, suggesting that the composition of sparfloxacin and indocyanine green or the self-assembled nanoparticles can enhance the sensitivity of bacteria to sparfloxacin through phototherapy.

[0045] The above experimental result data are summarized in Table 2 as follows.

[0046] Table 2 Minimum inhibitory concentrations (MICs) of combined use combinations against Staphylococcus aureus and Escherichia coli

[0047]

[0048]

[0049]

[0050] The antibiofilm properties of the self-assembled nanoparticles of sparfloxacin and indocyanine green against Staphylococcus aureus biofilm and Escherichia coli biofilm were investigated by the red tetrazolium chloride (TTC) method. 100 μL of a concentration of 10 was added into a 96-well plate 7A bacterial suspension of CFU / mL was statically cultured at 37 °C for 24 h to obtain a bacterial biofilm. The liquid in the wells was discarded and washed three times with normal saline. For the experimental wells, 100 μL of the solution of self-assembled nanoparticles of sparfloxacin and indocyanine green and 100 μL of broth medium were added. For the growth control wells, 200 μL of broth medium was added. For the sterile control wells, no bacterial suspension was added at the beginning of the experiment, only 100 μL of broth medium was added. After 24 h, the liquid in the wells was discarded, washed three times with normal saline, and 200 μL of broth medium was added. In terms of the concentration measurement of sparfloxacin, for Staphylococcus aureus, the SPX concentrations were 0.875, 1.75, 3.5, 7, 14 μg / mL respectively, and for Escherichia coli, the SPX concentrations were 0.4375, 0.875, 1.75, 3.5, 7 μg / mL respectively. In terms of the concentration measurement of indocyanine green, for Staphylococcus aureus, the ICG concentrations were 3.5, 7, 14, 28, 56 μg / mL respectively, and for Escherichia coli, the ICG concentrations were 1.75, 3.5, 7, 14, 28 μg / mL respectively. After dark incubation at 37 °C for 30 min, for the experimental wells, laser irradiation at 808 nm with a light intensity of 2.0 W / cm 2 was performed for 4 min. The above 96-well plates were placed at 37 °C for static culture for 20 h. 20 μL of TTC red tetrazolium solution was added and statically cultured at 37 °C for 2 h. The liquid in the wells was discarded, washed three times with normal saline, and DMSO was added to extract the red formazan generated by the bacterial metabolism of red tetrazolium in the biofilm. The absorbance of each well was measured at 492 nm using a microplate reader, and the biofilm metabolic rate was calculated according to formula (2).

[0051]

[0052] In the formula, OD1 = absorbance of the experimental wells, OD2 = absorbance of the growth control wells, OD3 = absorbance of the sterile control wells.

[0053] The above method was used to investigate the anti-biofilm performance of the combination of sparfloxacin and indocyanine green against Staphylococcus aureus biofilm and Escherichia coli biofilm. Replace "self-assembled nanoparticles of sparfloxacin and indocyanine green" with "combination of sparfloxacin and indocyanine green", and the mass ratio of sparfloxacin to indocyanine green is 1:4.

[0054] The above method was used to investigate the anti-biofilm performance of indocyanine green against Staphylococcus aureus biofilm and Escherichia coli biofilm. Replace "self-assembled nanoparticles of sparfloxacin and indocyanine green" with "indocyanine green".

[0055] The above method was used to investigate the anti-biofilm properties of sparfloxacin against Staphylococcus aureus biofilm and Escherichia coli biofilm. Replace "self-assembled nanoparticles of sparfloxacin and indocyanine green" with "sparfloxacin", and cancel "After incubating in the dark at 37 °C for 30 min, for the experimental wells, irradiate with 808 nm laser with a light intensity of 2.0 W / cm 2 for 4 min".

[0056] The CompuSyn software was used to calculate the combination index (CI) of self-assembled nanoparticles of sparfloxacin and indocyanine green, and the combination of sparfloxacin and indocyanine green. When CI < 1, it indicates that the combined use of the two drugs has a synergistic effect, and the smaller the CI value, the stronger the synergistic effect. The calculation results show that for Staphylococcus aureus, the CIs of self-assembled nanoparticles of sparfloxacin and indocyanine green, and the combination of sparfloxacin and indocyanine green are 0.212 and 0.509 respectively. For Escherichia coli, the CIs of self-assembled nanoparticles of sparfloxacin and indocyanine green, and the combination of sparfloxacin and indocyanine green are 0.106 and 0.343 respectively, indicating that both binary components of the nanoparticles and the combination have a synergistic therapeutic effect, and the synergistic therapeutic effect of the nanoparticles is better. The above experimental result data are summarized in Table 3 as follows.

[0057] Table 3 Combination index (CI) of combined use against Staphylococcus aureus and Escherichia coli

[0058]

[0059] Example 2

[0060] Evaluation of antibacterial properties of the combination of norfloxacin (NOX) and indocyanine green (ICG) against Staphylococcus aureus and Escherichia coli

[0061] Preparation of self-assembled nanoparticles with a mass ratio of norfloxacin to indocyanine green of 1:1: Weigh 0.8 mg of norfloxacin and add it to 1 mL of dimethyl sulfoxide for dissolution to obtain a dimethyl sulfoxide solution of norfloxacin. Weigh 0.5 mg of indocyanine green and add it to 2 mL of water for dissolution to obtain an aqueous solution of indocyanine green. Take 0.5 mL of the dimethyl sulfoxide solution of norfloxacin and slowly add it dropwise to 1.6 mL of the aqueous solution of indocyanine green. After the addition is complete, stir for 4 h. Dialyze for 4 h using a dialysis bag (MWC = 3500) and sonicate for 20 min to obtain self-assembled nanoparticles with a mass ratio of norfloxacin to indocyanine green of 1:1.

[0062] Preparation of self-assembled nanoparticles with a mass ratio of norfloxacin to indocyanine green of 2:1: According to the preparation method of self-assembled nanoparticles with a mass ratio of norfloxacin to indocyanine green of 1:1, replace "weigh 0.8 mg of norfloxacin" with "weigh 1.6 mg of norfloxacin" to obtain self-assembled nanoparticles with a mass ratio of norfloxacin to indocyanine green of 2:1.

[0063] Preparation of self-assembled nanoparticles with a mass ratio of norfloxacin to indocyanine green of 4:1: According to the preparation method of self-assembled nanoparticles with a mass ratio of norfloxacin to indocyanine green of 1:1, replace "weigh 0.8 mg of norfloxacin" with "weigh 3.2 mg of norfloxacin", and self-assembled nanoparticles with a mass ratio of norfloxacin to indocyanine green of 4:1 can be obtained.

[0064] The particle sizes of the self-assembled nanoparticles prepared with different mass ratios of norfloxacin to indocyanine green as above were measured by a Brookhaven nanoparticle size analyzer (Brookhaven Instruments Corporation, USA), and the results are shown in Table 4.

[0065] Table 4 Characterization of the particle sizes of self-assembled nanoparticles prepared with different mass ratios of norfloxacin to indocyanine green

[0066]

[0067] As can be seen from Table 4, the particle size of the self-assembled nanoparticles with a mass ratio of norfloxacin to indocyanine green of 2:1 is less than 200 nm, and the PDI is less than 0.2, which is the best mass ratio among the self-assembled nanoparticles prepared with the above three mass ratios. Subsequently, the self-assembled nanoparticles prepared with a mass ratio of norfloxacin to indocyanine green of 2:1 were used for antibacterial performance evaluation.

[0068] Referring to Example 1, the ratio of norfloxacin to indocyanine green in the self-assembled nanoparticles of norfloxacin and indocyanine green was detected by ultraviolet spectrophotometry, and the ratio (w:w) of norfloxacin to indocyanine green in the self-assembled nanoparticles was calculated to be 1:3.5.

[0069] According to the method in Example 1, the antibacterial properties of the nanoparticles, the composition, and the free antibiotic against Staphylococcus aureus and Escherichia coli were investigated. Among them, 0.2 mg and 0.4 mg, 0.2 mg and 0.7 mg, 0.2 mg and 1.0 mg of norfloxacin and indocyanine green were weighed respectively, and 5 mL of water was added to completely dissolve them, and norfloxacin and indocyanine green composition solutions with mass ratios of 1:2, 1:3.5, and 1:5 were obtained respectively. Measured by the concentration of norfloxacin, for Staphylococcus aureus, the NOX concentrations in the 1st to 10th wells were 0.04, 0.08, 0.16, 0.32, 0.64, 1.28, 2.56, 5.12, 10.24, 20.48 μg / mL respectively, and for Escherichia coli, the NOX concentrations in the 1st to 10th wells were 0.0025, 0.005, 0.01, 0.02, 0.04, 0.08, 0.16, 0.32, 0.64, 1.28 μg / mL respectively.

[0070] For Staphylococcus aureus, the MIC of norfloxacin is 1.251 μg / mL, and the MICs of the norfloxacin and indocyanine green compositions (w:w = 1:2, w:w = 1:3.5, w:w = 1:5) are 0.9633 μg / mL, 0.6672 μg / mL, and 0.4059 μg / mL, respectively. The MIC of the norfloxacin and indocyanine green self-assembled nanoparticles (w:w = 1:3.5) is 0.6065 μg / mL. This indicates that Staphylococcus aureus is more sensitive to the norfloxacin and indocyanine green compositions or self-assembled nanoparticles than to norfloxacin alone, suggesting that the norfloxacin and indocyanine green compositions or self-assembled nanoparticles can enhance the sensitivity of bacteria to norfloxacin through phototherapy.

[0071] For Escherichia coli, the MIC of norfloxacin is 0.08021 μg / mL, and the MICs of the norfloxacin and indocyanine green compositions (w:w = 1:2, w:w = 1:3.5, w:w = 1:5) are 0.05643 μg / mL, 0.02195 μg / mL, and 0.009893 μg / mL, respectively. The MIC of the norfloxacin and indocyanine green self-assembled nanoparticles (w:w = 1:3.5) is 0.01021 μg / mL. This indicates that Escherichia coli is more sensitive to the norfloxacin and indocyanine green compositions or self-assembled nanoparticles than to norfloxacin alone, suggesting that the norfloxacin and indocyanine green compositions or self-assembled nanoparticles can enhance the sensitivity of bacteria to norfloxacin through phototherapy. The above experimental result data are summarized in Table 2.

[0072] Examine the anti-biofilm properties of the nanoparticles, compositions, and free antibiotics against Staphylococcus aureus biofilms and Escherichia coli biofilms according to the method described in Example 1. Among them, the mass ratio of the physical combination of norfloxacin and indocyanine green is 1:3.5, which is the same as the ratio of the two in the nanoparticles. Measured by the concentration of norfloxacin, for Staphylococcus aureus, the NOX concentrations are 12.5, 25, 50, 100, and 200 μg / mL, respectively; for Escherichia coli, the NOX concentrations are 2, 4, 8, 16, and 32 μg / mL, respectively. Measured by the concentration of indocyanine green, for Staphylococcus aureus, the ICG concentrations are 43.75, 87.5, 175, 350, and 700 μg / mL, respectively; for Escherichia coli, the ICG concentrations are 7, 14, 28, 56, and 112 μg / mL, respectively.

[0073] The CompuSyn software was used to calculate the combination index (CI) of norfloxacin and indocyanine green self-assembled nanoparticles and the combination of norfloxacin and indocyanine green. When CI < 1, it indicates that the combination of the two drugs has a synergistic effect, and the smaller the CI value, the stronger the synergistic effect. The calculation results show that for Staphylococcus aureus, the CIs of norfloxacin and indocyanine green self-assembled nanoparticles and the combination of norfloxacin and indocyanine green are 0.661 and 0.859 respectively; for Escherichia coli, the CIs of norfloxacin and indocyanine green self-assembled nanoparticles and the combination of norfloxacin and indocyanine green are 0.431 and 0.537 respectively, indicating that the binary components of the nanoparticles and the combination both have a synergistic therapeutic effect, and the synergistic therapeutic effect of the nanoparticles is better.

[0074] Example 3

[0075] Antibacterial performance evaluation of the combination of ciprofloxacin CIX and indocyanine green ICG against Staphylococcus aureus and Escherichia coli

[0076] Preparation of self-assembled nanoparticles with a mass ratio of ciprofloxacin to indocyanine green of 1.5:1: Weigh 1.2 mg of ciprofloxacin and dissolve it in 1 mL of dimethyl sulfoxide to obtain a dimethyl sulfoxide solution of ciprofloxacin. Weigh 1 mg of indocyanine green and dissolve it in 2 mL of water to obtain an aqueous solution of indocyanine green. Take 0.5 mL of the dimethyl sulfoxide solution of ciprofloxacin and slowly add it dropwise to 0.8 mL of the aqueous solution of indocyanine green. After the addition is complete, stir for 2 h. Dialyze for 5 h using a dialysis bag (MWC = 3500) and sonicate for 15 min to obtain self-assembled nanoparticles with a mass ratio of ciprofloxacin to indocyanine green of 1.5:1.

[0077] Preparation of self-assembled nanoparticles with a mass ratio of ciprofloxacin to indocyanine green of 2:1: According to the preparation method of self-assembled nanoparticles with a mass ratio of ciprofloxacin to indocyanine green of 1.5:1, replace "weigh 1.2 mg of ciprofloxacin" with "weigh 1.6 mg of ciprofloxacin" to obtain self-assembled nanoparticles with a mass ratio of ciprofloxacin to indocyanine green of 2:1.

[0078] Preparation of self-assembled nanoparticles with a mass ratio of ciprofloxacin to indocyanine green of 2.5:1: According to the preparation method of self-assembled nanoparticles with a mass ratio of ciprofloxacin to indocyanine green of 1.5:1, replace "weigh 1.2 mg of ciprofloxacin" with "weigh 2 mg of ciprofloxacin" to obtain self-assembled nanoparticles with a mass ratio of ciprofloxacin to indocyanine green of 2.5:1.

[0079] The particle sizes of the self-assembled nanoparticles prepared with different mass ratios of ciprofloxacin and indocyanine green were measured by a Brookhaven nanoparticle size analyzer (Brookhaven Instruments Corporation, USA) and are shown in Table 5.

[0080] Table 5 Particle size characterization of self-assembled nanoparticles prepared from ciprofloxacin and indocyanine green with different mass ratios

[0081]

[0082] As can be seen from Table 5, the particle size of the self-assembled nanoparticles with a mass ratio of ciprofloxacin to indocyanine green of 2.5:1 is less than 300 nm and the PDI is less than 0.2, which is the optimal mass ratio among the self-assembled nanoparticles prepared using the above three mass ratios. Subsequently, the self-assembled nanoparticles prepared with a mass ratio of ciprofloxacin to indocyanine green of 2.5:1 were used for antibacterial performance evaluation.

[0083] Referring to Example 1, the ultraviolet spectrophotometry was used to detect the ratio of the two in the ciprofloxacin and indocyanine green self-assembled nanoparticles. The calculated ratio (w:w) of ciprofloxacin to indocyanine green in the self-assembled nanoparticles was 1:3.3.

[0084] According to the method in Example 1, the antibacterial performances of the nanoparticles, the composition, and the free antibiotic against Staphylococcus aureus and Escherichia coli were investigated. Among them, 0.2 mg and 0.46 mg, 0.2 mg and 0.66 mg, 0.2 mg and 0.86 mg of ciprofloxacin and indocyanine green were weighed respectively, and 10 mL of water was added to completely dissolve them to obtain ciprofloxacin and indocyanine green composition solutions with mass ratios of 1:2.3, 1:3.3, and 1:4.3 respectively. Measured by the concentration of ciprofloxacin, for Staphylococcus aureus, the CIX concentrations in the 1st to 10th wells were 0.02, 0.04, 0.08, 0.16, 0.32, 0.64, 1.28, 2.56, 5.12, 10.24 μg / mL respectively, and for Escherichia coli, the CIX concentrations in the 1st to 10th wells were 0.000625, 0.00125, 0.0025, 0.005, 0.01, 0.02, 0.04, 0.08, 0.16, 0.32 μg / mL respectively.

[0085] For Staphylococcus aureus, the MIC of ciprofloxacin was 0.3115 μg / mL, the MICs of the ciprofloxacin and indocyanine green compositions (w:w = 1:2.3, w:w = 1:3.3, w:w = 1:4.3) were 0.1493 μg / mL, 0.08327 μg / mL, and 0.04593 μg / mL respectively, and the MIC of the ciprofloxacin and indocyanine green self-assembled nanoparticles (w:w = 1:3.3) was 0.06355 μg / mL, indicating that Staphylococcus aureus was more sensitive to the ciprofloxacin and indocyanine green composition or self-assembled nanoparticles than to ciprofloxacin, suggesting that the ciprofloxacin and indocyanine green composition or self-assembled nanoparticles could enhance the sensitivity of bacteria to ciprofloxacin through phototherapy.

[0086] For Escherichia coli, the MIC of ciprofloxacin is 0.01035 μg / mL, and the MICs of the ciprofloxacin and indocyanine green compositions (w:w = 1:2.3, w:w = 1:3.3, w:w = 1:4.3) are 0.007345 μg / mL, 0.004379 μg / mL, and 0.001398 μg / mL, respectively. The MIC of the ciprofloxacin and indocyanine green self-assembled nanoparticles (w:w = 1:3.3) is 0.004357 μg / mL, indicating that Escherichia coli is more sensitive to the ciprofloxacin and indocyanine green compositions or self-assembled nanoparticles than to ciprofloxacin, suggesting that the ciprofloxacin and indocyanine green compositions or self-assembled nanoparticles can enhance the sensitivity of bacteria to ciprofloxacin through phototherapy. The above experimental result data are summarized in Table 2 as follows.

[0087] The anti-biofilm properties of the nanoparticles, compositions, and free antibiotics against Staphylococcus aureus biofilms and Escherichia coli biofilms were investigated according to the method in Example 1. Among them, the mass ratio of the physical combination of ciprofloxacin and indocyanine green is 1:3.3, which is the same as the ratio of the two in the nanoparticles. Measured by the concentration of ciprofloxacin, for Staphylococcus aureus, the CIX concentrations are 7.5, 15, 30, 60, and 120 μg / mL, and for Escherichia coli, the CIX concentrations are 0.25, 0.5, 1, 2, and 4 μg / mL. Measured by the concentration of indocyanine green, for Staphylococcus aureus, the ICG concentrations are 24.75, 49.5, 99, 198, and 396 μg / mL, and for Escherichia coli, the ICG concentrations are 1.155, 2.31, 4.62, 9.24, and 18.48 μg / mL.

[0088] The combination index (CI) of the ciprofloxacin and indocyanine green self-assembled nanoparticles and the ciprofloxacin and indocyanine green compositions was calculated using CompuSyn software. When CI < 1, it indicates that the combination of the two drugs has a synergistic effect, and the smaller the CI value, the stronger the synergistic effect. The calculation results show that for Staphylococcus aureus, the CIs of the ciprofloxacin and indocyanine green self-assembled nanoparticles and the ciprofloxacin and indocyanine green compositions are 0.163 and 0.395, respectively, and for Escherichia coli, the CIs of the ciprofloxacin and indocyanine green self-assembled nanoparticles and the ciprofloxacin and indocyanine green compositions are 0.181 and 0.312, respectively, indicating that the binary components of the nanoparticles and the compositions both have a synergistic therapeutic effect, and the synergistic therapeutic effect of the nanoparticles is better. The above experimental result data are summarized in Table 3 as follows.

[0089] Example 4

[0090] Evaluation of the antibacterial properties of the combination of levofloxacin (LEX) and indocyanine green (ICG) against Staphylococcus aureus and Escherichia coli

[0091] Preparation of self-assembled nanoparticles with a mass ratio of levofloxacin to indocyanine green of 3:1: Weigh 3 mg of levofloxacin and dissolve it in 1 mL of dimethyl sulfoxide to obtain a dimethyl sulfoxide solution of levofloxacin. Weigh 1 mg of indocyanine green and dissolve it in 4 mL of water to obtain an aqueous solution of indocyanine green. Take 0.5 mL of the dimethyl sulfoxide solution of levofloxacin and slowly add it dropwise to 2 mL of the aqueous solution of indocyanine green. After the addition is completed, stir for 3 h. Dialyze for 4 h using a dialysis bag (MWC = 3500), and then ultrasonicate for 15 min to obtain self-assembled nanoparticles with a mass ratio of levofloxacin to indocyanine green of 3:1.

[0092] Preparation of self-assembled nanoparticles with a mass ratio of levofloxacin to indocyanine green of 4:1: According to the preparation method of self-assembled nanoparticles with a mass ratio of levofloxacin to indocyanine green of 3:1, replace "weigh 3 mg of levofloxacin" with "weigh 4 mg of levofloxacin" to obtain self-assembled nanoparticles with a mass ratio of levofloxacin to indocyanine green of 4:1.

[0093] Preparation of self-assembled nanoparticles with a mass ratio of levofloxacin to indocyanine green of 5:1: According to the preparation method of self-assembled nanoparticles with a mass ratio of levofloxacin to indocyanine green of 3:1, replace "weigh 3 mg of levofloxacin" with "weigh 5 mg of levofloxacin" to obtain self-assembled nanoparticles with a mass ratio of levofloxacin to indocyanine green of 5:1.

[0094] The particle sizes of the self-assembled nanoparticles prepared with different mass ratios of levofloxacin to indocyanine green as described above were measured by a Brookhaven nanoparticle size analyzer (Brookhaven Instruments Corporation, USA) and are shown in Table 6.

[0095] Table 6 Particle size characterization of self-assembled nanoparticles prepared with different mass ratios of levofloxacin to indocyanine green

[0096]

[0097] As can be seen from Table 6, the self-assembled nanoparticles with a mass ratio of levofloxacin to indocyanine green of 3:1 have a particle size less than 300 nm and a PDI less than 0.2, which is the best mass ratio among the three mass ratios used to prepare self-assembled nanoparticles. Therefore, the self-assembled nanoparticles prepared with a mass ratio of levofloxacin to indocyanine green of 3:1 were used for antibacterial performance evaluation.

[0098] Referring to Example 1, the ratio of the two in the self-assembled nanoparticles of levofloxacin and indocyanine green was detected by ultraviolet spectrophotometry, and the ratio (w:w) of the two in the self-assembled nanoparticles of levofloxacin and indocyanine green was calculated to be 1:3.5.

[0099] The antibacterial properties of nanoparticles, compositions, and free antibiotics against Staphylococcus aureus and Escherichia coli were investigated by the method in Example 1. Among them, 0.2 mg and 0.3 mg, 0.2 mg and 0.7 mg, 0.2 mg and 1.1 mg of levofloxacin and indocyanine green were weighed respectively, and added to 10 mL of water to completely dissolve, thus obtaining levofloxacin and indocyanine green composition solutions with mass ratios of 1:1.5, 1:3.5, and 1:5.5 respectively. Measured by the concentration of levofloxacin, for Staphylococcus aureus, the LEX concentrations in the 1st to 10th wells were 0.02, 0.04, 0.08, 0.16, 0.32, 0.64, 1.28, 2.56, 5.12, 10.24 μg / mL respectively; for Escherichia coli, the LEX concentrations in the 1st to 10th wells were 0.0025, 0.005, 0.01, 0.02, 0.04, 0.08, 0.16, 0.32, 0.64, 1.28 μg / mL respectively.

[0100] For Staphylococcus aureus, the MIC of levofloxacin was 0.2853 μg / mL, and the MICs of the levofloxacin and indocyanine green compositions (w:w = 1:1.5, w:w = 1:3.5, w:w = 1:5.5) were 0.1321 μg / mL, 0.08765 μg / mL, and 0.04396 μg / mL respectively. The MIC of the self-assembled nanoparticles of levofloxacin and indocyanine green (w:w = 1:3.5) was 0.07561 μg / mL, indicating that Staphylococcus aureus was more sensitive to the levofloxacin and indocyanine green composition or self-assembled nanoparticles than to levofloxacin, suggesting that the levofloxacin and indocyanine green composition or self-assembled nanoparticles could enhance the sensitivity of bacteria to levofloxacin through phototherapy.

[0101] For Escherichia coli, the MIC of levofloxacin was 0.03496 μg / mL, and the MICs of the levofloxacin and indocyanine green compositions (w:w = 1:1.5, w:w = 1:3.5, w:w = 1:5.5) were 0.01734 μg / mL, 0.009543 μg / mL, and 0.005389 μg / mL respectively. The MIC of the self-assembled nanoparticles of levofloxacin and indocyanine green (w:w = 1:3.5) was 0.007386 μg / mL, indicating that Escherichia coli was more sensitive to the levofloxacin and indocyanine green composition or self-assembled nanoparticles than to levofloxacin, suggesting that the levofloxacin and indocyanine green composition or self-assembled nanoparticles could enhance the sensitivity of bacteria to levofloxacin through phototherapy. The above experimental result data are summarized in Table 2.

[0102] The anti - biofilm properties of nanoparticles, compositions, and free antibiotics against Staphylococcus aureus biofilm and Escherichia coli biofilm were investigated by the method in Example 1. Among them, the mass ratio of the physical combination of levofloxacin and indocyanine green is 1:3.5, which is the same as the ratio of the two in the nanoparticles. Measured by the concentration of levofloxacin, for Staphylococcus aureus, the LEX concentrations are 7, 14, 28, 56, 112 μg / mL respectively, and for Escherichia coli, the LEX concentrations are 1, 2, 4, 8, 16 μg / mL respectively. Measured by the concentration of indocyanine green, for Staphylococcus aureus, the ICG concentrations are 24.5, 49, 98, 196, 392 μg / mL respectively, and for Escherichia coli, the ICG concentrations are 3.5, 7, 14, 28, 56 μg / mL respectively.

[0103] The CompuSyn software was used to calculate the combination index (CI) of the self - assembled nanoparticles of levofloxacin and indocyanine green and the composition of levofloxacin and indocyanine green. When CI < 1, it indicates that the combination of the two drugs has a synergistic effect, and the smaller the CI value, the stronger the synergistic effect. The calculation results show that for Staphylococcus aureus, the CIs of the self - assembled nanoparticles of levofloxacin and indocyanine green and the composition of levofloxacin and indocyanine green are 0.235 and 0.433 respectively, and for Escherichia coli, the CIs of the self - assembled nanoparticles of levofloxacin and indocyanine green and the composition of levofloxacin and indocyanine green are 0.295 and 0.467 respectively, indicating that the binary components of the nanoparticles and the composition both have synergistic therapeutic effects, and the synergistic therapeutic effect of the nanoparticles is better. The above experimental result data are summarized in Table 3.

[0104] Example 5

[0105] Evaluation of the antibacterial properties of the combination of gatifloxacin (GAX) and indocyanine green (ICG) against Staphylococcus aureus and Escherichia coli

[0106] Preparation of self - assembled nanoparticles with a mass ratio of gatifloxacin to indocyanine green of 1:1: Weigh 1 mg of gatifloxacin and add it to 1 mL of dimethyl sulfoxide for dissolution to obtain a dimethyl sulfoxide solution of gatifloxacin. Weigh 0.5 mg of indocyanine green and add it to 2 mL of water for dissolution to obtain an aqueous solution of indocyanine green. Take 0.5 mL of the dimethyl sulfoxide solution of gatifloxacin and slowly add it dropwise to 2 mL of the aqueous solution of indocyanine green. After the addition is completed, stir for 4 h. Dialyze for 6 h using a dialysis bag (MWC = 3500) and then sonicate for 20 min to obtain self - assembled nanoparticles with a mass ratio of gatifloxacin to indocyanine green of 1:1.

[0107] Preparation of self-assembled nanoparticles with a mass ratio of gatifloxacin to indocyanine green of 3:1: According to the preparation method of self-assembled nanoparticles with a mass ratio of gatifloxacin to indocyanine green of 1:1, replace "weigh 1 mg of gatifloxacin" with "weigh 3 mg of gatifloxacin", and self-assembled nanoparticles with a mass ratio of gatifloxacin to indocyanine green of 3:1 can be obtained.

[0108] Preparation of self-assembled nanoparticles with a mass ratio of gatifloxacin to indocyanine green of 5:1: According to the preparation method of self-assembled nanoparticles with a mass ratio of gatifloxacin to indocyanine green of 1:1, replace "weigh 1 mg of gatifloxacin" with "weigh 5 mg of gatifloxacin", and self-assembled nanoparticles with a mass ratio of gatifloxacin to indocyanine green of 5:1 can be obtained.

[0109] The particle sizes of the self-assembled nanoparticles prepared with gatifloxacin and indocyanine green at different mass ratios were measured by a Brookhaven nanoparticle size analyzer (Brookhaven Instruments Corporation, USA), as shown in Table 7.

[0110] Table 7 Particle size characterization of self-assembled nanoparticles prepared with gatifloxacin and indocyanine green at different mass ratios

[0111]

[0112] As can be seen from Table 7, the self-assembled nanoparticles with a mass ratio of gatifloxacin to indocyanine green of 3:1 have a particle size less than 200 nm and a PDI less than 0.25, which is the best mass ratio among the self-assembled nanoparticles prepared with the above three mass ratios. Therefore, the self-assembled nanoparticles prepared with a mass ratio of gatifloxacin to indocyanine green of 3:1 are used for antibacterial performance evaluation.

[0113] Referring to Example 1, the ratio of gatifloxacin to indocyanine green in the self-assembled nanoparticles was detected by ultraviolet spectrophotometry, and the ratio (w:w) of gatifloxacin to indocyanine green in the self-assembled nanoparticles was calculated to be 1:2.3.

[0114] The antibacterial properties of nanoparticles, the composition, and free antibiotics against Staphylococcus aureus and Escherichia coli were investigated according to the method in Example 1. Among them, the masses of gatifloxacin and indocyanine green were weighed as 0.2 mg and 0.3 mg, 0.2 mg and 0.46 mg, 0.2 mg and 0.62 mg, respectively, and added to 40 mL of water to be completely dissolved, thus obtaining gatifloxacin and indocyanine green composition solutions with mass ratios of 1:1.5, 1:2.3, and 1:3.1, respectively. Measured by the concentration of gatifloxacin, for Staphylococcus aureus, the GAX concentrations in the 1st to 10th wells were 0.005, 0.01, 0.02, 0.04, 0.08, 0.16, 0.32, 0.64, 1.28, 2.56 μg / mL, respectively; for Escherichia coli, the GAX concentrations in the 1st to 10th wells were 0.00125, 0.0025, 0.005, 0.01, 0.02, 0.04, 0.08, 0.16, 0.32, 0.64 μg / mL, respectively.

[0115] For Staphylococcus aureus, the MIC of gatifloxacin was 0.07523 μg / mL, and the MICs of the gatifloxacin and indocyanine green compositions (w:w = 1:1.5, w:w = 1:2.3, w:w = 1:3.1) were 0.05143 μg / mL, 0.02564 μg / mL, and 0.008539 μg / mL, respectively. The MIC of the self-assembled nanoparticles of gatifloxacin and indocyanine green (w:w = 1:2.3) was 0.02716 μg / mL, indicating that Staphylococcus aureus was more sensitive to the gatifloxacin and indocyanine green composition or the self-assembled nanoparticles than to gatifloxacin, suggesting that the gatifloxacin and indocyanine green composition or the self-assembled nanoparticles could enhance the sensitivity of bacteria to gatifloxacin through phototherapy.

[0116] For Escherichia coli, the MIC of gatifloxacin was 0.01935 μg / mL, and the MICs of the gatifloxacin and indocyanine green compositions (w:w = 1:1.5, w:w = 1:2.3, w:w = 1:3.1) were 0.009137 μg / mL, 0.006593 μg / mL, and 0.002358 μg / mL, respectively. The MIC of the self-assembled nanoparticles of gatifloxacin and indocyanine green (w:w = 1:2.3) was 0.006763 μg / mL, indicating that Escherichia coli was more sensitive to the gatifloxacin and indocyanine green composition or the self-assembled nanoparticles than to gatifloxacin, suggesting that the gatifloxacin and indocyanine green composition or the self-assembled nanoparticles could enhance the sensitivity of bacteria to gatifloxacin through phototherapy. The above experimental result data are summarized in Table 2.

[0117] The anti-biofilm properties of nanoparticles, compositions, and free antibiotics against Staphylococcus aureus biofilms and Escherichia coli biofilms were investigated by the method in Example 1. Among them, the mass ratio of the physical combination of gatifloxacin and indocyanine green was 1:2.3, which was consistent with the ratio of the two in the nanoparticles. Measured by the concentration of gatifloxacin, for Staphylococcus aureus, the GAX concentrations were 2, 4, 8, 16, 32 μg / mL, and for Escherichia coli, the GAX concentrations were 0.5, 1, 2, 4, 8 μg / mL. Measured by the concentration of indocyanine green, for Staphylococcus aureus, the ICG concentrations were 4.6, 9.2, 18.4, 36.8, 73.6 μg / mL, and for Escherichia coli, the ICG concentrations were 1.15, 2.3, 4.6, 9.2, 18.4 μg / mL.

[0118] The combination index (CI) of gatifloxacin and indocyanine green self-assembled nanoparticles and the composition of gatifloxacin and indocyanine green was calculated using CompuSyn software. When CI < 1, it indicated that the combination of the two drugs had a synergistic effect, and the smaller the CI value, the stronger the synergistic effect. The calculation results showed that for Staphylococcus aureus, the CIs of gatifloxacin and indocyanine green self-assembled nanoparticles and the composition of gatifloxacin and indocyanine green were 0.324 and 0.637 respectively, and for Escherichia coli, the CIs of gatifloxacin and indocyanine green self-assembled nanoparticles and the composition of gatifloxacin and indocyanine green were 0.256 and 0.573 respectively, indicating that both binary components of the nanoparticles and the composition had a synergistic therapeutic effect, and the synergistic therapeutic effect of the nanoparticles was better. The above experimental result data are summarized in Table 3.

[0119] Example 6

[0120] Evaluation of the antibacterial properties of the combination of moxifloxacin (MOX) and indocyanine green (ICG) against Staphylococcus aureus and Escherichia coli

[0121] Preparation of self-assembled nanoparticles with a mass ratio of moxifloxacin to indocyanine green of 2:1: Weigh 2 mg of moxifloxacin and add it to 1 mL of dimethyl sulfoxide for dissolution to obtain a dimethyl sulfoxide solution of moxifloxacin. Weigh 0.5 mg of indocyanine green and add it to 2 mL of water for dissolution to obtain an aqueous solution of indocyanine green. Take 0.5 mL of the dimethyl sulfoxide solution of moxifloxacin and slowly add it dropwise to 2 mL of the aqueous solution of indocyanine green. After the addition is complete, stir for 5 h. Dialyze for 6 h using a dialysis bag (MWC = 3500) and sonicate for 20 min to obtain self-assembled nanoparticles with a mass ratio of moxifloxacin to indocyanine green of 2:1.

[0122] Preparation of self-assembled nanoparticles with a mass ratio of moxifloxacin to indocyanine green of 3:1: According to the preparation method of self-assembled nanoparticles with a mass ratio of moxifloxacin to indocyanine green of 2:1, replace "weigh 2 mg of moxifloxacin" with "weigh 3 mg of moxifloxacin", and self-assembled nanoparticles with a mass ratio of moxifloxacin to indocyanine green of 3:1 can be obtained.

[0123] Preparation of self-assembled nanoparticles with a mass ratio of moxifloxacin to indocyanine green of 4:1: According to the preparation method of self-assembled nanoparticles with a mass ratio of moxifloxacin to indocyanine green of 2:1, replace "weigh 2 mg of moxifloxacin" with "weigh 4 mg of moxifloxacin", and self-assembled nanoparticles with a mass ratio of moxifloxacin to indocyanine green of 4:1 can be obtained.

[0124] The particle sizes of the self-assembled nanoparticles prepared with moxifloxacin and indocyanine green at different mass ratios were measured by a Brookhaven nanoparticle size analyzer (Brookhaven Instruments Corporation, USA), as shown in Table 8.

[0125] Table 8 Characterization of the particle sizes of self-assembled nanoparticles prepared with moxifloxacin and indocyanine green at different mass ratios

[0126]

[0127] As can be seen from Table 8, the particle size of the self-assembled nanoparticles with a mass ratio of moxifloxacin to indocyanine green of 3:1 is less than 200 nm, and the PDI is less than 0.2, which is the best mass ratio among the self-assembled nanoparticles prepared with the above three mass ratios. Therefore, the self-assembled nanoparticles prepared with a mass ratio of moxifloxacin to indocyanine green of 3:1 are used for antibacterial performance evaluation.

[0128] Referring to Example 1, the ratio of the two in the self-assembled nanoparticles of moxifloxacin and indocyanine green was detected by ultraviolet spectrophotometry. The calculated ratio (w:w) of the two in the self-assembled nanoparticles of moxifloxacin and indocyanine green was 1:4.6.

[0129] The antibacterial properties of nanoparticles, compositions, and free antibiotics against Staphylococcus aureus and Escherichia coli were investigated by the method in Example 1. Among them, 0.2 mg and 0.46 mg, 0.2 mg and 0.92 mg, 0.2 mg and 1.38 mg of moxifloxacin and indocyanine green were weighed respectively, and 40 mL of water was added to completely dissolve them, obtaining moxifloxacin and indocyanine green composition solutions with mass ratios of 1:2.3, 1:4.6, and 1:6.9 respectively. Measured by the concentration of moxifloxacin, for Staphylococcus aureus, the MOX concentrations in the 1st to 10th wells were 0.005, 0.01, 0.02, 0.04, 0.08, 0.16, 0.32, 0.64, 1.28, 2.56 μg / mL respectively; for Escherichia coli, the MOX concentrations in the 1st to 10th wells were 0.00125, 0.0025, 0.005, 0.01, 0.02, 0.04, 0.08, 0.16, 0.32, 0.64 μg / mL respectively.

[0130] For Staphylococcus aureus, the MIC of moxifloxacin was 0.06753 μg / mL, and the MICs of moxifloxacin and indocyanine green compositions (w:w = 1:2.3, w:w = 1:4.6, w:w = 1:6.9) were 0.04015 μg / mL, 0.01264 μg / mL, and 0.005354 μg / mL respectively. The MIC of the self-assembled nanoparticles of moxifloxacin and indocyanine green (w:w = 1:4.6) was 0.01023 μg / mL, indicating that Staphylococcus aureus was more sensitive to moxifloxacin and indocyanine green compositions or self-assembled nanoparticles than to moxifloxacin, suggesting that moxifloxacin and indocyanine green compositions or self-assembled nanoparticles could enhance the sensitivity of bacteria to moxifloxacin through phototherapy.

[0131] For Escherichia coli, the MIC of moxifloxacin was 0.03415 μg / mL, and the MICs of moxifloxacin and indocyanine green compositions (w:w = 1:2.3, w:w = 1:4.6, w:w = 1:6.9) were 0.01391 μg / mL, 0.006354 μg / mL, and 0.002804 μg / mL respectively. The MIC of the self-assembled nanoparticles of moxifloxacin and indocyanine green (w:w = 1:4.6) was 0.005673 μg / mL, indicating that Escherichia coli was more sensitive to moxifloxacin and indocyanine green compositions or self-assembled nanoparticles than to moxifloxacin, suggesting that moxifloxacin and indocyanine green compositions or self-assembled nanoparticles could enhance the sensitivity of bacteria to moxifloxacin through phototherapy. The above experimental result data are summarized in Table 2.

[0132] The anti-biofilm properties of nanoparticles, compositions, and free antibiotics against Staphylococcus aureus biofilms and Escherichia coli biofilms were investigated according to the method in Example 1. Among them, the mass ratio of the physical combination of moxifloxacin and indocyanine green was 1:4.6, which was consistent with the ratio of the two in the nanoparticles. Measured by the concentration of moxifloxacin, for Staphylococcus aureus, the MOX concentrations were 1.5, 3, 6, 12, 24 μg / mL respectively, and for Escherichia coli, the MOX concentrations were 0.875, 1.75, 3.5, 7, 14 μg / mL respectively. Measured by the concentration of indocyanine green, for Staphylococcus aureus, the ICG concentrations were 6.9, 13.8, 27.6, 55.2, 110.4 μg / mL respectively, and for Escherichia coli, the ICG concentrations were 4.025, 8.05, 16.1, 32.2, 64.4 μg / mL respectively.

[0133] The combination index (CI) of moxifloxacin and indocyanine green self-assembled nanoparticles and the composition of moxifloxacin and indocyanine green was calculated using CompuSyn software. When CI < 1, it indicated that the combination of the two drugs had a synergistic effect, and the smaller the CI value, the stronger the synergistic effect. The calculation results showed that for Staphylococcus aureus, the CIs of moxifloxacin and indocyanine green self-assembled nanoparticles and the composition of moxifloxacin and indocyanine green were 0.231 and 0.602 respectively, and for Escherichia coli, the CIs of moxifloxacin and indocyanine green self-assembled nanoparticles and the composition of moxifloxacin and indocyanine green were 0.324 and 0.553 respectively, indicating that the binary components of the nanoparticles and the composition both had synergistic therapeutic effects, and the synergistic therapeutic effect of the nanoparticles was better. The above experimental result data are summarized in Table 3.

[0134] Example 7

[0135] Antibacterial performance evaluation of the combination of vancomycin (VAN) and indocyanine green (ICG) against Staphylococcus aureus

[0136] Preparation of self-assembled nanoparticles with a mass ratio of vancomycin to indocyanine green of 5:1: Weigh 10 mg of vancomycin and add 1 mL of dimethyl sulfoxide to dissolve it to obtain a dimethyl sulfoxide solution of vancomycin. Weigh 1 mg of indocyanine green and add 2 mL of water to dissolve it to obtain an aqueous solution of indocyanine green. Take 0.5 mL of the dimethyl sulfoxide solution of vancomycin and slowly drip it into 2 mL of the aqueous solution of indocyanine green. After the dripping is completed, stir for 6 h. Dialyze for 6 h using a dialysis bag (MWC = 3500) and then sonicate for 10 min to obtain self-assembled nanoparticles with a mass ratio of vancomycin to indocyanine green of 5:1.

[0137] Preparation of self-assembled nanoparticles with a mass ratio of vancomycin to indocyanine green of 10:1: According to the preparation method of self-assembled nanoparticles with a mass ratio of vancomycin to indocyanine green of 5:1, replace "weigh 10 mg of vancomycin" with "weigh 20 mg of vancomycin", and self-assembled nanoparticles with a mass ratio of vancomycin to indocyanine green of 10:1 can be obtained.

[0138] Preparation of self-assembled nanoparticles with a mass ratio of vancomycin to indocyanine green of 15:1: According to the preparation method of self-assembled nanoparticles with a mass ratio of vancomycin to indocyanine green of 5:1, replace "weigh 10 mg of vancomycin" with "weigh 30 mg of vancomycin", and self-assembled nanoparticles with a mass ratio of vancomycin to indocyanine green of 15:1 can be obtained.

[0139] The particle sizes of the self-assembled nanoparticles prepared with vancomycin and indocyanine green at different mass ratios were measured by a Brookhaven nanometer particle size analyzer (Brookhaven Instruments Corporation, USA), as shown in Table 9.

[0140] Table 9 Particle size characterization of self-assembled nanoparticles prepared with vancomycin and indocyanine green at different mass ratios

[0141]

[0142] As can be seen from Table 9, the particle size of the self-assembled nanoparticles with a mass ratio of vancomycin to indocyanine green of 10:1 is less than 200 nm, and the PDI is less than 0.2, which is the best mass ratio among the self-assembled nanoparticles prepared with the above three mass ratios. Therefore, the self-assembled nanoparticles prepared with a mass ratio of vancomycin to indocyanine green of 10:1 were used for antibacterial performance evaluation.

[0143] Referring to Example 1, the ratio of the two in the self-assembled nanoparticles of vancomycin and indocyanine green was detected by ultraviolet spectrophotometry. The calculated ratio (w:w) of the two in the self-assembled nanoparticles of vancomycin and indocyanine green was 5:1.

[0144] The method for investigating the antibacterial properties of nanoparticles, compositions, and free antibiotics against Staphylococcus aureus according to the method in Example 1. Replace "self-assembled nanoparticles of sparfloxacin and indocyanine green", "composition of sparfloxacin and indocyanine green", and "sparfloxacin" with "self-assembled nanoparticles of vancomycin and indocyanine green", "composition of vancomycin and indocyanine green", and "vancomycin" respectively, and the antibacterial property results of self-assembled nanoparticles of vancomycin and indocyanine green, composition of vancomycin and indocyanine green, and vancomycin against Staphylococcus aureus can be obtained. Among them, the masses of vancomycin and indocyanine green weighed are 2.5 mg and 1 mg, 5 mg and 1 mg, and 10 mg and 1 mg respectively, and they are added to 10 mL of water to be completely dissolved, and the composition solutions of vancomycin and indocyanine green with mass ratios of 2.5:1, 5:1, and 10:1 are obtained respectively. Measured by the concentration of vancomycin, the VAN concentrations in the 1st to 10th wells are 0.078125, 0.15625, 0.3125, 0.625, 1.25, 2.5, 5, 10, 20, 40 μg / mL respectively.

[0145] The MIC of vancomycin is 1.253 μg / mL, and the MICs of the composition of vancomycin and indocyanine green (w:w = 2.5:1, w:w = 5:1, w:w = 10:1) are 0.9451 μg / mL, 0.5634 μg / mL, and 0.1126 μg / mL respectively, and the MIC of the self-assembled nanoparticles of vancomycin and indocyanine green (w:w = 5:1) is 0.5089 μg / mL, indicating that Staphylococcus aureus is more sensitive to the composition of vancomycin and indocyanine green or self-assembled nanoparticles than to vancomycin, suggesting that the composition of vancomycin and indocyanine green or self-assembled nanoparticles can enhance the sensitivity of bacteria to vancomycin through phototherapy. The above experimental result data are summarized in Table 2.

[0146] According to the method in Example 1, investigate the anti-biofilm properties of nanoparticles, compositions, and free antibiotics against the biofilm of Staphylococcus aureus. Among them, the mass ratio of the physical combination of vancomycin and indocyanine green is 5:1, which is the same as the ratio of the two in the nanoparticles. Measured by the concentration of vancomycin, the VAN concentrations are 15.625, 31.25, 62.5, 125, 250 μg / mL respectively. Measured by the concentration of indocyanine green, the ICG concentrations are 3.125, 6.25, 12.5, 25, 50 μg / mL respectively.

[0147] The CompuSyn software was used to calculate the combination index (CI) of vancomycin and indocyanine green self-assembled nanoparticles and the combination of vancomycin and indocyanine green. When CI < 1, it indicates that the combination of the two drugs has a synergistic effect, and the smaller the CI value, the stronger the synergistic effect. The calculation results show that the CIs of vancomycin and indocyanine green self-assembled nanoparticles and the combination of vancomycin and indocyanine green are 0.523 and 0.732 respectively, indicating that both binary components of the nanoparticles and the combination have a synergistic therapeutic effect, and the synergistic therapeutic effect of the nanoparticles is better. The above experimental result data are summarized in Table 3 as follows.

[0148] Example 8

[0149] Evaluation of the antibacterial properties of the combination of teicoplanin TEI and indocyanine green ICG against Staphylococcus aureus

[0150] Preparation of self-assembled nanoparticles with a mass ratio of teicoplanin to indocyanine green of 5:1: Weigh 10 mg of teicoplanin and dissolve it in 1 mL of dimethyl sulfoxide to prepare a dimethyl sulfoxide solution of teicoplanin. Weigh 1 mg of indocyanine green and dissolve it in 2 mL of water to prepare an aqueous solution of indocyanine green. Take 0.5 mL of the dimethyl sulfoxide solution of teicoplanin and slowly add it dropwise to 2 mL of the aqueous solution of indocyanine green. After the addition is completed, stir for 4 h. Dialyze for 5 h using a dialysis bag (MWC = 3500), and then sonicate for 15 min to obtain self-assembled nanoparticles with a mass ratio of teicoplanin to indocyanine green of 5:1.

[0151] Preparation of self-assembled nanoparticles with a mass ratio of teicoplanin to indocyanine green of 7.5:1: According to the preparation method of self-assembled nanoparticles with a mass ratio of teicoplanin to indocyanine green of 5:1, replace "weigh 10 mg of teicoplanin" with "weigh 15 mg of teicoplanin", and self-assembled nanoparticles with a mass ratio of teicoplanin to indocyanine green of 7.5:1 can be obtained.

[0152] Preparation of self-assembled nanoparticles with a mass ratio of teicoplanin to indocyanine green of 10:1: According to the preparation method of self-assembled nanoparticles with a mass ratio of teicoplanin to indocyanine green of 5:1, replace "weigh 10 mg of teicoplanin" with "weigh 20 mg of teicoplanin", and self-assembled nanoparticles with a mass ratio of teicoplanin to indocyanine green of 10:1 can be obtained.

[0153] The particle sizes of the self-assembled nanoparticles prepared with different mass ratios of teicoplanin and indocyanine green were measured by a Brookhaven nanoparticle size analyzer (Brookhaven Instruments Corporation, USA), and the results are shown in Table 10.

[0154] Table 10 Particle size characterization of self-assembled nanoparticles prepared with different mass ratios of teicoplanin and indocyanine green

[0155]

[0156] As can be seen from Table 10, the particle size of the self-assembled nanoparticles with a mass ratio of teicoplanin to indocyanine green of 7.5:1 is less than 200 nm, and the PDI is less than 0.2, which is the best mass ratio among the self-assembled nanoparticles prepared using the above three mass ratios. Therefore, the self-assembled nanoparticles prepared with a mass ratio of teicoplanin to indocyanine green of 7.5:1 were used for antibacterial performance evaluation.

[0157] Referring to Example 1, the ultraviolet spectrophotometry was used to detect the ratio of the two in the self-assembled nanoparticles of teicoplanin and indocyanine green. The calculated ratio (w:w) of teicoplanin to indocyanine green in the self-assembled nanoparticles was 6:1.

[0158] According to the method in Example 1, the antibacterial properties of the nanoparticles, the composition, and the free antibiotic against Staphylococcus aureus were investigated. Among them, 4.8 mg and 1.6 mg, 9.6 mg and 1.6 mg, 14.4 mg and 1.6 mg of teicoplanin and indocyanine green were weighed respectively, and 40 mL of water was added to completely dissolve them, obtaining teicoplanin and indocyanine green composition solutions with mass ratios of 3:1, 6:1, and 9:1 respectively. Taking the teicoplanin concentration as the measurement, the TEI concentrations in the 1st to 10th wells were 0.0390625, 0.078125, 0.15625, 0.3125, 0.625, 1.25, 2.5, 5, 10, 20 μg / mL respectively.

[0159] The MIC of teicoplanin was 0.6251 μg / mL, the MICs of the teicoplanin and indocyanine green compositions (w:w = 3:1, w:w = 6:1, w:w = 9:1) were 0.3954 μg / mL, 0.1578 μg / mL, and 0.05116 μg / mL respectively, and the MIC of the self-assembled nanoparticles of teicoplanin and indocyanine green (w:w = 6:1) was 0.1308 μg / mL, indicating that Staphylococcus aureus was more sensitive to the teicoplanin and indocyanine green composition or the self-assembled nanoparticles than to teicoplanin, suggesting that the teicoplanin and indocyanine green composition or the self-assembled nanoparticles can enhance the sensitivity of bacteria to teicoplanin through phototherapy. The above experimental result data are summarized in Table 2 as follows.

[0160] The anti-biofilm properties of nanoparticles, compositions, and free antibiotics against Staphylococcus aureus biofilms were investigated by the method in Example 1. Among them, the mass ratio of the physical combination of teicoplanin and indocyanine green was 6:1, which was consistent with the ratio of the two in the nanoparticles. Measured by the concentration of teicoplanin, the TEI concentrations were 7.8125, 15.625, 31.25, 62.5, and 125 μg / mL, respectively. Measured by the concentration of indocyanine green, the ICG concentrations were 1.3, 2.6, 5.2, 10.4, and 20.8 μg / mL, respectively.

[0161] The combination index (CI) of the self-assembled nanoparticles of teicoplanin and indocyanine green and the composition of teicoplanin and indocyanine green was calculated using CompuSyn software. When CI < 1, it indicated that the combination of the two drugs had a synergistic effect, and the smaller the CI value, the stronger the synergistic effect. The calculation results showed that the CIs of the self-assembled nanoparticles of teicoplanin and indocyanine green and the composition of teicoplanin and indocyanine green were 0.433 and 0.572, respectively, indicating that the binary components of the nanoparticles and the composition both had synergistic therapeutic effects, and the synergistic therapeutic effect of the nanoparticles was better. The above experimental result data are summarized in Table 3.

[0162] Example 9

[0163] Evaluation of the antibacterial properties of the combination of sparfloxacin (SPX), vancomycin (VAN), and indocyanine green (ICG) against Staphylococcus aureus and Escherichia coli

[0164] Preparation of self-assembled nanoparticles with a mass ratio of sparfloxacin, vancomycin, and indocyanine green of 1:5:1: Weigh 2 mg of sparfloxacin and add it to 1 mL of dimethyl sulfoxide for dissolution to obtain a dimethyl sulfoxide solution of sparfloxacin. Weigh 10 mg of vancomycin and add it to 1 mL of dimethyl sulfoxide for dissolution to obtain a dimethyl sulfoxide solution of vancomycin. Take 0.5 mL of the dimethyl sulfoxide solution of sparfloxacin and 0.5 mL of the dimethyl sulfoxide solution of vancomycin, mix them thoroughly to obtain a dimethyl sulfoxide mixed solution of sparfloxacin and vancomycin. Weigh 0.5 mg of indocyanine green and add it to 2 mL of water for dissolution to obtain an aqueous solution of indocyanine green. Take 0.5 mL of the dimethyl sulfoxide mixed solution of sparfloxacin and vancomycin and slowly add it dropwise to 2 mL of the aqueous solution of indocyanine green. After the addition is completed, stir for 8 h. Dialyze for 6 h using a dialysis bag (MWC = 3500) and then sonicate for 30 min to obtain self-assembled nanoparticles with a mass ratio of sparfloxacin, vancomycin, and indocyanine green of 1:5:1.

[0165] Preparation of self - assembled nanoparticles with a mass ratio of sparfloxacin, vancomycin and indocyanine green of 1:10:1: According to the preparation method of self - assembled nanoparticles with a mass ratio of sparfloxacin, vancomycin and indocyanine green of 1:5:1, replace "weigh 10 mg of vancomycin" with "weigh 20 mg of vancomycin", and the self - assembled nanoparticles with a mass ratio of sparfloxacin, vancomycin and indocyanine green of 1:10:1 can be obtained.

[0166] Preparation of self - assembled nanoparticles with a mass ratio of sparfloxacin, vancomycin and indocyanine green of 1.5:10:1: According to the preparation method of self - assembled nanoparticles with a mass ratio of sparfloxacin, vancomycin and indocyanine green of 1:5:1, replace "weigh 2 mg of sparfloxacin" with "weigh 3 mg of sparfloxacin" and "weigh 10 mg of vancomycin" with "weigh 20 mg of vancomycin", and the self - assembled nanoparticles with a mass ratio of sparfloxacin, vancomycin and indocyanine green of 1.5:10:1 can be obtained.

[0167] The particle sizes of the self - assembled nanoparticles prepared with different mass ratios of sparfloxacin, vancomycin and indocyanine green were measured by a Brookhaven nanoparticle size analyzer (Brookhaven Instruments Corporation, USA) as shown in Table 11.

[0168] Table 11 Particle size characterization of self - assembled nanoparticles prepared with different mass ratios of sparfloxacin, vancomycin and indocyanine green

[0169]

[0170] As can be seen from Table 11, the particle size of the self - assembled nanoparticles with a mass ratio of sparfloxacin, vancomycin and indocyanine green of 1:5:1 is less than 200 nm, and the PDI is less than 0.25, which is the best mass ratio among the self - assembled nanoparticles prepared with the above three mass ratios. Therefore, the self - assembled nanoparticles prepared with a mass ratio of sparfloxacin, vancomycin and indocyanine green of 1:5:1 are used for antibacterial performance evaluation.

[0171] Referring to Example 1, the proportions of the three components in the self - assembled nanoparticles of sparfloxacin, vancomycin and indocyanine green were detected by ultraviolet spectrophotometry. The calculated proportions (w:w:w) of sparfloxacin, vancomycin and indocyanine green in the self - assembled nanoparticles were 1:20:3.

[0172] The antibacterial properties of nanoparticles, compositions, and free antibiotics against Staphylococcus aureus and Escherichia coli were investigated according to the method in Example 1. Among them, the masses of sparfloxacin, vancomycin, and indocyanine green were weighed as 0.2 mg, 2 mg, and 0.3 mg, 0.2 mg, 4 mg, and 0.6 mg, and 0.2 mg, 6 mg, and 1.2 mg, respectively, and added to 40 mL of water to be completely dissolved, obtaining sparfloxacin, vancomycin, and indocyanine green composition solutions with mass ratios of 1:10:1.5, 1:20:3, and 1:30:6, respectively. Measured by the concentration of sparfloxacin, for Staphylococcus aureus, the SPX concentrations in the 1st to 10th wells were 0.000625, 0.00125, 0.0025, 0.005, 0.01, 0.02, 0.04, 0.08, 0.16, and 0.32 μg / mL, respectively; for Escherichia coli, the SPX concentrations in the 1st to 10th wells were 0.00015625, 0.0003125, 0.000625, 0.00125, 0.0025, 0.005, 0.01, 0.02, 0.04, and 0.08 μg / mL, respectively.

[0173] For Staphylococcus aureus, the MIC of sparfloxacin was 0.08167 μg / mL, the MIC of vancomycin was 1.156 μg / mL, and the MICs of the compositions of sparfloxacin, vancomycin, and indocyanine green (w:w:w = 1:10:1.5, w:w:w = 1:20:3, w:w:w = 1:30:6) were SPX = 0.01403 μg / mL and VAN = 0.1489 μg / mL, SPX = 0.004677 μg / mL and VAN = 0.04254 μg / mL, and SPX = 0.001563 μg / mL and VAN = 0.01702 μg / mL, respectively. The MIC of the self-assembled nanoparticles of sparfloxacin, vancomycin, and indocyanine green (w:w:w = 1:20:3) was SPX = 0.003056 μg / mL and VAN = 0.02751 μg / mL, indicating that Staphylococcus aureus was more sensitive to the compositions or self-assembled nanoparticles of sparfloxacin, vancomycin, and indocyanine green than to sparfloxacin or vancomycin alone, suggesting that the compositions or self-assembled nanoparticles of sparfloxacin, vancomycin, and indocyanine green could enhance the sensitivity of bacteria to sparfloxacin or vancomycin through phototherapy.

[0174] For Escherichia coli, the MIC of sparfloxacin is 0.01063 μg / mL. The MICs (measured by SPX concentration) of the sparfloxacin, vancomycin, and indocyanine green composition (w:w:w = 1:10:1.5, w:w:w = 1:20:3, w:w:w = 1:30:6) are 0.003193 μg / mL, 0.001063 μg / mL, and 0.0004381 μg / mL respectively. The MIC (measured by SPX concentration) of the self-assembled nanoparticles of sparfloxacin, vancomycin, and indocyanine green (w:w:w = 1:20:3) is 0.0006563 μg / mL, indicating that Escherichia coli is more sensitive to the sparfloxacin, vancomycin, and indocyanine green composition or self-assembled nanoparticles than to sparfloxacin or vancomycin alone, suggesting that the sparfloxacin, vancomycin, and indocyanine green composition or self-assembled nanoparticles can enhance the sensitivity of bacteria to sparfloxacin or vancomycin through phototherapy. The above experimental result data are summarized in Table 2 as follows.

[0175] Example 10

[0176] Evaluation of the antibacterial properties of the combination of fleroxacin FLE and indocyanine green ICG against Staphylococcus aureus and Escherichia coli

[0177] Preparation of self-assembled nanoparticles with a mass ratio of fleroxacin to indocyanine green of 3:1: Weigh 3 mg of fleroxacin and dissolve it in 1 mL of dimethyl sulfoxide to prepare a dimethyl sulfoxide solution of fleroxacin. Weigh 0.5 mg of indocyanine green and dissolve it in 2 mL of water to prepare an aqueous solution of indocyanine green. Take 0.5 mL of the dimethyl sulfoxide solution of fleroxacin and slowly add it dropwise to 2 mL of the aqueous solution of indocyanine green. After the addition is completed, stir for 6 h. Dialyze for 6 h using a dialysis bag (MWC = 3500), and then ultrasonicate for 20 min to obtain self-assembled nanoparticles with a mass ratio of fleroxacin to indocyanine green of 3:1.

[0178] Similarly, prepare self-assembled nanoparticles with a mass ratio of fleroxacin to indocyanine green of 4:1 and self-assembled nanoparticles with a mass ratio of fleroxacin to indocyanine green of 5:1.

[0179] The particle sizes of the self-assembled nanoparticles prepared with different mass ratios of fleroxacin and indocyanine green were measured by a Brookhaven nanoparticle size analyzer (Brookhaven Instruments Corporation, USA) and are shown in Table 12.

[0180] Table 12 Characterization of the particle sizes of self-assembled nanoparticles prepared with different mass ratios of fleroxacin and indocyanine green

[0181]

[0182] As can be seen from Table 12, the particle size of the self-assembled nanoparticles with a mass ratio of fleroxacin to indocyanine green of 5:1 is less than 250 nm, and the PDI is less than 0.2, which is the best mass ratio among the self-assembled nanoparticles prepared using the above three mass ratios. Therefore, the self-assembled nanoparticles prepared with a mass ratio of fleroxacin to indocyanine green of 5:1 were used for antibacterial performance evaluation.

[0183] Referring to Example 1, the ultraviolet spectrophotometry was used to detect the ratio of fleroxacin to indocyanine green in the self-assembled nanoparticles. The calculated ratio (w:w) of fleroxacin to indocyanine green in the self-assembled nanoparticles was 1:5.

[0184] According to the method in Example 1, the antibacterial performances of the nanoparticles, the composition, and the free antibiotic against Staphylococcus aureus and Escherichia coli were investigated. Among them, 0.2 mg and 0.6 mg, 0.2 mg and 1 mg, 0.2 mg and 1.4 mg of fleroxacin and indocyanine green were weighed respectively, and 10 mL of water was added to completely dissolve them, obtaining fleroxacin and indocyanine green composition solutions with mass ratios of 1:3, 1:5, and 1:7 respectively. Taking the fleroxacin concentration as the measurement, for Staphylococcus aureus, the FLE concentrations in the 1st to 10th wells were 0.02, 0.04, 0.08, 0.16, 0.32, 0.64, 1.28, 2.56, 5.12, 10.24 μg / mL respectively, and for Escherichia coli, the FLE concentrations in the 1st to 10th wells were 0.0025, 0.005, 0.01, 0.02, 0.04, 0.08, 0.16, 0.32, 0.64, 1.28 μg / mL respectively.

[0185] For Staphylococcus aureus, the MIC of fleroxacin was 0.62351 μg / mL, the MICs of the fleroxacin and indocyanine green compositions (w:w = 1:3, w:w = 1:5, w:w = 1:7) were 0.60768 μg / mL, 0.59453 μg / mL, and 0.56213 μg / mL respectively, and the MIC of the fleroxacin and indocyanine green self-assembled nanoparticles (w:w = 1:5) was 0.60265 μg / mL, indicating that the sensitivity of Staphylococcus aureus to the fleroxacin and indocyanine green composition or self-assembled nanoparticles was similar to its sensitivity to fleroxacin, suggesting that the fleroxacin and indocyanine green composition or self-assembled nanoparticles could not enhance the sensitivity of bacteria to fleroxacin through phototherapy.

[0186] For Escherichia coli, the MIC of fleroxacin is 0.07543 μg / mL, and the MICs of the fleroxacin and indocyanine green compositions (w:w = 1:3, w:w = 1:5, w:w = 1:7) are 0.07365 μg / mL, 0.07057 μg / mL, and 0.06943 μg / mL respectively. The MIC of the self-assembled nanoparticles of fleroxacin and indocyanine green (w:w = 1:5) is 0.07198 μg / mL, indicating that the sensitivity of Escherichia coli to the fleroxacin and indocyanine green compositions or self-assembled nanoparticles is similar to its sensitivity to fleroxacin, suggesting that the fleroxacin and indocyanine green compositions or self-assembled nanoparticles cannot enhance the sensitivity of bacteria to fleroxacin through phototherapy. The above experimental result data are summarized in Table 2 as follows.

[0187] The anti-biofilm properties of the nanoparticles, compositions, and free antibiotics against Staphylococcus aureus biofilms and Escherichia coli biofilms were investigated according to the method in Example 1. Among them, the mass ratio of the physical combination of fleroxacin and indocyanine green is 1:5, which is consistent with the ratio of the two in the nanoparticles. Measured by the concentration of fleroxacin, for Staphylococcus aureus, the FLE concentrations are 6, 12, 24, 48, 96 μg / mL respectively, and for Escherichia coli, the FLE concentrations are 3.5, 7, 14, 28, 56 μg / mL respectively. Measured by the concentration of indocyanine green, for Staphylococcus aureus, the ICG concentrations are 30, 60, 120, 240, 480 μg / mL respectively, and for Escherichia coli, the ICG concentrations are 17.5, 35, 70, 140, 280 μg / mL respectively.

[0188] The drug combination index (Combination Index, CI) of the self-assembled nanoparticles of fleroxacin and indocyanine green and the fleroxacin and indocyanine green compositions was calculated using CompuSyn software. When CI < 1, it indicates that the combination of the two drugs has a synergistic effect, and the smaller the CI value, the stronger the synergistic effect. The calculation results show that for Staphylococcus aureus, the CIs of the self-assembled nanoparticles of fleroxacin and indocyanine green and the fleroxacin and indocyanine green compositions are 0.975 and 0.963 respectively, and for Escherichia coli, the CIs of the self-assembled nanoparticles of fleroxacin and indocyanine green and the fleroxacin and indocyanine green compositions are 0.987 and 0.989 respectively, indicating that the binary components of the nanoparticles and compositions have almost no synergistic therapeutic effect. The above experimental result data are summarized in Table 3 as follows.

[0189] Example 11

[0190] Evaluation of the antibacterial properties of the combination of clinafloxacin CFN and indocyanine green ICG against Staphylococcus aureus and Escherichia coli

[0191] Preparation of self-assembled nanoparticles with a mass ratio of clinafloxacin to indocyanine green of 3:1: Weigh 3 mg of clinafloxacin and dissolve it in 1 mL of dimethyl sulfoxide to prepare a dimethyl sulfoxide solution of clinafloxacin. Weigh 0.5 mg of indocyanine green and dissolve it in 2 mL of water to prepare an aqueous solution of indocyanine green. Take 0.5 mL of the dimethyl sulfoxide solution of clinafloxacin and slowly add it dropwise to 2 mL of the aqueous solution of indocyanine green. After the addition is complete, stir for 4 h. Dialyze for 6 h using a dialysis bag (MWC = 3500) and sonicate for 15 min to obtain self-assembled nanoparticles with a mass ratio of clinafloxacin to indocyanine green of 3:1.

[0192] Similarly, prepare self-assembled nanoparticles with a mass ratio of clinafloxacin to indocyanine green of 6:1 and self-assembled nanoparticles with a mass ratio of clinafloxacin to indocyanine green of 9:1.

[0193] The particle sizes of the self-assembled nanoparticles prepared with different mass ratios of clinafloxacin to indocyanine green were measured by a Brookhaven nanoparticle size analyzer (Brookhaven Instruments Corporation, USA) as shown in Table 13.

[0194] Table 13 Characterization of the particle sizes of self-assembled nanoparticles prepared with different mass ratios of clinafloxacin to indocyanine green

[0195]

[0196] As can be seen from Table 13, the particle size of the self-assembled nanoparticles with a mass ratio of clinafloxacin to indocyanine green of 6:1 is less than 200 nm and the PDI is less than 0.2, which is the best mass ratio among the self-assembled nanoparticles prepared using the above three mass ratios. Therefore, the self-assembled nanoparticles prepared with a mass ratio of clinafloxacin to indocyanine green of 6:1 are used for antibacterial performance evaluation.

[0197] Referring to Example 1, the ratio of the two in the self-assembled nanoparticles of clinafloxacin and indocyanine green was detected by ultraviolet spectrophotometry. The calculated ratio (w:w) of the two in the self-assembled nanoparticles of clinafloxacin and indocyanine green was 1:10.

[0198] The method for investigating the antibacterial properties of nanoparticles, compositions, and free antibiotics against Staphylococcus aureus and Escherichia coli according to the method in Example 1. Among them, 0.2 mg and 1 mg, 0.2 mg and 2 mg, and 0.2 mg and 4 mg of clinafloxacin and indocyanine green were weighed respectively, and added to 40 mL of water to be completely dissolved, obtaining clinafloxacin and indocyanine green composition solutions with mass ratios of 1:5, 1:10, and 1:20 respectively. Measured by the concentration of clinafloxacin, for Staphylococcus aureus, the CFN concentrations in the 1st to 10th wells were 0.00125, 0.0025, 0.005, 0.01, 0.02, 0.04, 0.08, 0.16, 0.32, and 0.64 μg / mL respectively, and for Escherichia coli, the CFN concentrations in the 1st to 10th wells were 0.000625, 0.00125, 0.0025, 0.005, 0.01, 0.02, 0.04, 0.08, 0.16, and 0.32 μg / mL respectively.

[0199] For Staphylococcus aureus, the MIC of clinafloxacin was 0.03412 μg / mL, and the MICs of the clinafloxacin and indocyanine green compositions (w:w = 1:5, w:w = 1:10, w:w = 1:20) were 0.03065 μg / mL, 0.02971 μg / mL, and 0.02993 μg / mL respectively, and the MIC of the self-assembled nanoparticles of clinafloxacin and indocyanine green (w:w = 1:10) was 0.03011 μg / mL, indicating that the sensitivity of Staphylococcus aureus to the clinafloxacin and indocyanine green composition or self-assembled nanoparticles was similar to its sensitivity to clinafloxacin, suggesting that the clinafloxacin and indocyanine green composition or self-assembled nanoparticles could not enhance the sensitivity of bacteria to clinafloxacin through phototherapy.

[0200] For Escherichia coli, the MIC of clinafloxacin was 0.008534 μg / mL, and the MICs of the clinafloxacin and indocyanine green compositions (w:w = 1:5, w:w = 1:10, w:w = 1:20) were 0.007543 μg / mL, 0.007325 μg / mL, and 0.007024 μg / mL respectively, and the MIC of the self-assembled nanoparticles of clinafloxacin and indocyanine green (w:w = 1:10) was 0.007189 μg / mL, indicating that the sensitivity of Escherichia coli to the clinafloxacin and indocyanine green composition or self-assembled nanoparticles was similar to its sensitivity to clinafloxacin, suggesting that the clinafloxacin and indocyanine green composition or self-assembled nanoparticles could not enhance the sensitivity of bacteria to clinafloxacin through phototherapy. The above experimental result data are summarized in Table 2 as follows.

[0201] The method in Example 1 was used to investigate the anti-biofilm properties of nanoparticles, compositions, and free antibiotics against Staphylococcus aureus biofilms and Escherichia coli biofilms. Among them, the mass ratio of the physical combination of clinafloxacin and indocyanine green was 1:10, which was the same as the ratio of the two in the nanoparticles. Measured by the concentration of clinafloxacin, for Staphylococcus aureus, the CFN concentrations were 0.375, 0.75, 1.5, 3, 6 μg / mL, and for Escherichia coli, the CFN concentrations were 0.21875, 0.4375, 0.875, 1.75, 3.5 μg / mL. Measured by the concentration of indocyanine green, for Staphylococcus aureus, the ICG concentrations were 3.75, 7.5, 15, 30, 60 μg / mL, and for Escherichia coli, the ICG concentrations were 2.1875, 4.375, 8.75, 17.5, 35 μg / mL.

[0202] The CompuSyn software was used to calculate the combination index (CI) of the self-assembled nanoparticles of clinafloxacin and indocyanine green and the composition of clinafloxacin and indocyanine green. When CI < 1, it indicates that the combination of the two drugs has a synergistic effect, and the smaller the CI value, the stronger the synergistic effect. The calculation results showed that for Staphylococcus aureus, the CIs of the self-assembled nanoparticles of clinafloxacin and indocyanine green and the composition of clinafloxacin and indocyanine green were 1.021 and 1.032 respectively, and for Escherichia coli, the CIs of the self-assembled nanoparticles of clinafloxacin and indocyanine green and the composition of clinafloxacin and indocyanine green were 1.033 and 1.098 respectively, indicating that the binary components of the nanoparticles and the composition had almost no synergistic therapeutic effect. The above experimental result data are summarized in Table 3.

[0203] Example 12

[0204] Evaluation of the antibacterial properties of the combination of imipenem (IPM) and indocyanine green (ICG) against Staphylococcus aureus and Escherichia coli

[0205] Preparation of self-assembled nanoparticles with a mass ratio of imipenem to indocyanine green of 3:1: Weigh 3 mg of imipenem and dissolve it in 1 mL of dimethyl sulfoxide to prepare a dimethyl sulfoxide solution of imipenem. Weigh 0.5 mg of indocyanine green and dissolve it in 2 mL of water to prepare an aqueous solution of indocyanine green. Take 0.5 mL of the dimethyl sulfoxide solution of imipenem and slowly add it dropwise to 2 mL of the aqueous solution of indocyanine green. After the addition is completed, stir for 2 h. Dialyze for 4 h using a dialysis bag (MWC = 3500) and sonicate for 10 min to obtain self-assembled nanoparticles with a mass ratio of imipenem to indocyanine green of 3:1.

[0206] Similarly, self-assembled nanoparticles with a mass ratio of imipenem to indocyanine green of 5:1 and self-assembled nanoparticles with a mass ratio of imipenem to indocyanine green of 7:1 were prepared.

[0207] The particle sizes of the self-assembled nanoparticles prepared from imipenem and indocyanine green with different mass ratios were measured by a Brookhaven nanoparticle size analyzer (Brookhaven Instruments Corporation, USA), as shown in Table 14.

[0208] Table 14 Characterization of the particle sizes of self-assembled nanoparticles prepared from imipenem and indocyanine green with different mass ratios

[0209]

[0210] As can be seen from Table 14, the particle size of the self-assembled nanoparticles with a mass ratio of imipenem to indocyanine green of 5:1 is less than 200 nm, and the PDI is less than 0.2, which is the best mass ratio among the self-assembled nanoparticles prepared using the above three mass ratios. Therefore, the self-assembled nanoparticles prepared with a mass ratio of imipenem to indocyanine green of 5:1 were used for antibacterial performance evaluation.

[0211] Referring to Example 1, the ultraviolet spectrophotometry was used to detect the ratio of the two in the self-assembled nanoparticles of imipenem and indocyanine green. The calculated ratio (w:w) of imipenem to indocyanine green in the self-assembled nanoparticles was 1:10.

[0212] According to the method in Example 1, the antibacterial performances of the nanoparticles, the composition, and the free antibiotic against Staphylococcus aureus and Escherichia coli were investigated. Among them, 0.2 mg and 1 mg, 0.2 mg and 2 mg, 0.2 mg and 3 mg of imipenem and indocyanine green were weighed respectively, and 40 mL of water was added to completely dissolve them, obtaining imipenem and indocyanine green composition solutions with mass ratios of 1:5, 1:10, and 1:15 respectively. Measured by the concentration of imipenem, for Staphylococcus aureus, the IPM concentrations in the 1st to 10th wells were 0.00125, 0.0025, 0.005, 0.01, 0.02, 0.04, 0.08, 0.16, 0.32, 0.64 μg / mL respectively; for Escherichia coli, the IPM concentrations in the 1st to 10th wells were 0.005, 0.01, 0.02, 0.04, 0.08, 0.16, 0.32, 0.64, 1.28, 2.56 μg / mL respectively.

[0213] For Staphylococcus aureus, the MIC of imipenem is 0.03715 μg / mL, and the MICs of the imipenem and indocyanine green compositions (w:w = 1:5, w:w = 1:10, w:w = 1:15) are 0.03534 μg / mL, 0.03321 μg / mL, and 0.03053 μg / mL respectively. The MIC of the imipenem and indocyanine green self-assembled nanoparticles (w:w = 1:10) is 0.03456 μg / mL, indicating that the sensitivity of Staphylococcus aureus to the imipenem and indocyanine green compositions or self-assembled nanoparticles is similar to its sensitivity to imipenem, suggesting that the imipenem and indocyanine green compositions or self-assembled nanoparticles cannot enhance the sensitivity of bacteria to imipenem through phototherapy.

[0214] For Escherichia coli, the MIC of imipenem is 0.15543 μg / mL, and the MICs of the imipenem and indocyanine green compositions (w:w = 1:5, w:w = 1:10, w:w = 1:15) are 0.14543 μg / mL, 0.13241 μg / mL, and 0.12657 μg / mL respectively. The MIC of the imipenem and indocyanine green self-assembled nanoparticles (w:w = 1:10) is 0.14675 μg / mL, indicating that the sensitivity of Escherichia coli to the imipenem and indocyanine green compositions or self-assembled nanoparticles is similar to its sensitivity to imipenem, suggesting that the imipenem and indocyanine green compositions or self-assembled nanoparticles cannot enhance the sensitivity of bacteria to imipenem through phototherapy. The above experimental result data are summarized in Table 2.

[0215] Examine the anti-biofilm properties of nanoparticles, compositions, and free antibiotics against Staphylococcus aureus biofilms and Escherichia coli biofilms according to the method in Example 1. Among them, the mass ratio of the physical combination of imipenem and indocyanine green is 1:10, which is the same as the ratio of the two in the nanoparticles. Measured by the concentration of imipenem, for Staphylococcus aureus, the IPM concentrations are 0.375, 0.75, 1.5, 3, 6 μg / mL respectively, and for Escherichia coli, the IPM concentrations are 1.75, 3.5, 7, 14, 28 μg / mL respectively. Measured by the concentration of indocyanine green, for Staphylococcus aureus, the ICG concentrations are 3.75, 7.5, 15, 30, 60 μg / mL respectively, and for Escherichia coli, the ICG concentrations are 17.5, 35, 70, 140, 280 μg / mL respectively.

[0216] The CompuSyn software was used to calculate the combination index (CI) of imipenem and indocyanine green self-assembled nanoparticles and the combination of imipenem and indocyanine green. When CI < 1, it indicates that the combination of the two drugs has a synergistic effect, and the smaller the CI value, the stronger the synergistic effect. The calculation results show that for Staphylococcus aureus, the CIs of imipenem and indocyanine green self-assembled nanoparticles and the combination of imipenem and indocyanine green are 0.953 and 1.057 respectively, and for Escherichia coli, the CIs of imipenem and indocyanine green self-assembled nanoparticles and the combination of imipenem and indocyanine green are 0.997 and 1.043 respectively, indicating that the binary components of the nanoparticles and the combination have almost no synergistic therapeutic effect. The above experimental result data are summarized in Table 3 as follows.

Claims

1. Use of the combination of an antibiotic and indocyanine green in the preparation of a therapeutic agent for treating bacterial skin infections, characterized in that, The antibiotics are selected from sparfloxacin, norfloxacin, ciprofloxacin, levofloxacin, gatifloxacin, moxifloxacin or teicoplanin.

2. A therapeutic drug for bacterial skin infections, characterized in that: Comprising: an antibiotic and indocyanine green, and a pharmaceutically acceptable carrier; the antibiotics are selected from sparfloxacin, norfloxacin, ciprofloxacin, levofloxacin, gatifloxacin, moxifloxacin or teicoplanin.

3. The therapeutic drug for bacterial skin infections according to claim 2, characterized in that: The active ingredient of the therapeutic drug for bacterial skin infections is an antibiotic and indocyanine green.

4. The therapeutic drug for bacterial skin infections according to claim 2, wherein: The active ingredient of the therapeutic drug for bacterial skin infections is self-assembled nanoparticles made of an antibiotic and indocyanine green.

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