A gold nanorod@bovine serum albumin chiral sensor capable of realizing chiral recognition through temperature difference, a preparation method and applications thereof
A chiral sensor of gold nanorods@bovine serum albumin was prepared by seed growth method. The temperature difference recognition of chiral amino acid enantiomers was realized by utilizing the photothermal conversion temperature difference of gold nanorods. This solved the problem of expensive and complicated recognition methods in the prior art and realized low-cost and fast-response real-time analysis.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHANGZHOU UNIV
- Filing Date
- 2023-05-12
- Publication Date
- 2026-05-15
AI Technical Summary
Existing chiral amino acid identification technologies require expensive chiral columns and complex sample pretreatment processes, making them unsuitable for real-time analysis. Furthermore, there is a lack of low-cost, simple-to-operate, and fast-response identification methods.
Gold nanorods were prepared using a seed growth method. Bovine serum albumin was bound to the gold nanorods via gold-sulfur bonds. Chiral recognition was achieved by utilizing the difference in photothermal conversion temperature of the gold nanorods under near-infrared light irradiation.
This method enables the chiral identification of amino acid enantiomers based on temperature difference, offering advantages such as simple operation, low cost, and rapid response, making it suitable for real-time analysis.
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Figure CN116773593B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of chiral material preparation technology, specifically relating to a gold nanorod@bovine serum albumin chiral sensor that can achieve chiral recognition through temperature difference, its preparation method, and its application. Technical Background
[0002] Amino acids play a vital role in all living organisms, forming the basis of proteins and metabolic intermediates. Except for glycine, all other amino acids are chiral. Research on amino acid enantiomer recognition can provide crucial information, contributing to a better understanding of biological systems and further advancing biochemistry and drug research. Commonly used chiral separation techniques include high-performance liquid chromatography (HPLC), gas chromatography (GC), and capillary electrophoresis. However, these methods mostly require expensive chiral columns and complex sample pretreatment processes, making them unsuitable for real-time analysis. Temperature-differential chirality recognition technology, due to its advantages of low cost, simple operation, and rapid response, is a novel chiral recognition method. Its basic principle utilizes the difference in binding ability between chiral recognition materials containing photothermal reagents and amino acid enantiomers. This difference is manifested through the difference in photothermal conversion temperature rise of the photothermal reagent under near-infrared light irradiation, thus achieving temperature-differential chiral recognition of amino acid enantiomers.
[0003] Gold nanoparticles have attracted much attention in biosensors due to their large specific surface area, good biocompatibility, tunable size, and rapid electron transfer capabilities. Furthermore, gold nanoparticles exhibit surface plasmon resonance (SPR). When 808 nm near-infrared light irradiates the surface of gold nanoparticles, SPR excites electrons in the conduction band, causing coherent oscillations and generating significant heat, thus producing localized high temperatures. Compared to spherical gold nanoparticles, gold nanorods exhibit better photothermal conversion performance. Therefore, we can utilize the photothermal conversion effect of gold nanorods to read out temperature as a signal. This method offers advantages such as simple operation, low cost, rapid response, and high sensitivity. Summary of the Invention
[0004] To address the problems existing in the prior art, the present invention aims to design and provide a gold nanorod@bovine serum albumin chiral sensor, its preparation method, and its application, which enables chiral recognition through temperature difference. The present invention uses a seed growth method to prepare gold nanorods, and binds bovine serum albumin to the gold nanorods via gold-sulfur bonds to obtain gold nanorod@bovine serum albumin. The present invention utilizes the difference in binding ability between gold nanorod@bovine serum albumin and amino acid enantiomers, which is manifested by the difference in the photothermal conversion temperature increase of the gold nanorods under near-infrared light irradiation, thereby achieving temperature-dependent chiral recognition of amino acid enantiomers.
[0005] To achieve the above objectives, the present invention adopts the following technical solution:
[0006] On one hand, the present invention provides a gold nanorod@bovine serum albumin chiral sensor that can achieve chiral recognition through temperature difference. The gold nanorod solution is prepared by seed growth method, and bovine serum albumin is combined with gold nanorods through gold-sulfur bonds to obtain the gold nanorod@bovine serum albumin chiral sensor.
[0007] Secondly, the present invention provides a method for preparing a gold nanorod@bovine serum albumin chiral sensor that can achieve chiral recognition through temperature difference, characterized by comprising the following steps:
[0008] (1) A gold nanorod solution was prepared by seed growth method;
[0009] (2) Weigh bovine serum albumin and dissolve it in the gold nanorod solution obtained in step (1). Stir and, after the bovine serum albumin is completely dissolved, place it in an environment at 4°C for reaction.
[0010] The specific method for preparing the gold nanorod solution by seed growth in step (1) is as follows: (a) weigh hexadecyltrimethylammonium bromide and dissolve it in ultrapure water, add 0.5-1.5 wt% chloroauric acid solution, stir vigorously, add sodium borohydride solution, continue stirring until it turns brownish-yellow and stop stirring, and age it to obtain the gold seed solution; (b) weigh hexadecyltrimethylammonium bromide and sodium oleate, dissolve them in ultrapure water at 40-60℃, cool to 20-40℃, add silver nitrate solution, add chloroauric acid solution while stirring vigorously, mix evenly and let stand, stir for the first time, add concentrated hydrochloric acid to adjust the pH to 1-2, stir for the second time, add ascorbic acid solution, and stir vigorously for 20-40s;
[0011] (c) Add the gold seed solution, continue stirring for 20-40 seconds, let stand, centrifuge, wash several times with ultrapure water, dissolve the precipitate in ultrapure water, and obtain a gold nanorod solution.
[0012] In the preparation method described above, the mass-to-volume ratio of hexadecyltrimethylammonium bromide, chloroauric acid solution, and sodium borohydride solution in step (a) is 0.2–0.5 g: 50–150 μL: 0.3–0.8 mL; the concentration of the chloroauric acid solution is 0.5–2.5 mM, and the concentration of the sodium borohydride solution is 0.01–0.03 M; the mass-to-volume ratio of hexadecyltrimethylammonium bromide to ultrapure water is 0.2–0.5 g: 10 mL; and the aging conditions are: temperature 20–40 °C, time 15–40 min.
[0013] In the preparation method described above, the mass-to-volume ratio of hexadecyltrimethylammonium bromide, sodium oleate, and ultrapure water in step (b) is 1.2–1.6 g: 0.1–0.4 g: 50 mL; the volume ratio of hexadecyltrimethylammonium bromide, silver nitrate solution, chloroauric acid solution, concentrated hydrochloric acid, ascorbic acid solution, and gold seed solution is 1.2–1.6 g: 2–5 mL: 50 mL: 300–500 μL: 0.1–0.4 mL: 0.15 mL; the concentration of silver nitrate is 1–5 mM, the concentration of chloroauric acid is 0.5–2.5 mM, and the concentration of ascorbic acid is 0.03–0.09 M.
[0014] In the preparation method described above, the standing conditions in step (b) are: temperature 20-40℃, time 10-30min; the conditions for the first stirring are: speed 50-150rpm, time 60-120min; and the conditions for the second stirring are: speed 50-150rpm, time 10-30min.
[0015] In the preparation method described above, the standing conditions in step (c) are: temperature 20-40℃, time 10-14h; and the centrifugation conditions are: speed 8000-10000rpm, time 10-30min.
[0016] In the preparation method described above, the mass-to-volume ratio of bovine serum albumin to gold nanorod solution in step (2) is 6-10 mg: 2-8 mL; and the reaction time is 10-14 h.
[0017] Thirdly, the present invention provides the use of the gold nanorod@bovine serum albumin chiral sensor in the chiral recognition of amino acid enantiomers using temperature difference.
[0018] The intended use is characterized in that the amino acid includes Trp.
[0019] Compared with the prior art, the present invention has the following beneficial effects:
[0020] This invention uses a seed growth method to prepare gold nanorod solutions. Bovine serum albumin (BSA) is bound to gold nanorods via gold-sulfur bonds to obtain a gold nanorod@BSA solution. The difference in binding ability between gold nanorods@BSA and amino acid enantiomers is utilized, as reflected in the difference in the photothermal conversion temperature increase of the gold nanorods under near-infrared light irradiation, thereby achieving temperature-dependent chiral recognition of amino acid enantiomers. Attached Figure Description
[0021] Figure 1 This is a transmission electron microscope image of the gold nanorods in Example 1;
[0022] Figure 2This is a transmission electron microscope image of gold nanorods@bovine serum albumin in Example 1;
[0023] Figure 3 The visible absorption spectra of bovine serum albumin, gold nanorods, and gold nanorods@bovine serum albumin in Example 2 are shown below.
[0024] Figure 4 The full X-ray photoelectron spectrum of gold nanorods@bovine serum albumin in Example 3 is shown.
[0025] Figure 5 This is a high-resolution Au4f spectrum of the X-ray photoelectron spectroscopy of gold nanorods@bovine serum albumin in Example 3;
[0026] Figure 6 This is a high-resolution S2p spectrum of the X-ray photoelectron spectroscopy of gold nanorods@bovine serum albumin in Example 3;
[0027] Figure 7 This is a temperature-time curve of gold nanorods@bovine serum albumin and Trp enantiomers in Example 4. Detailed Implementation
[0028] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments. The following embodiments are intended to illustrate the present invention and not to further limit the present invention.
[0029] Example 1:
[0030] The preparation of gold nanorods@bovine serum albumin for temperature-differential recognition of Trp enantiomers includes the following steps:
[0031] (1) Preparation of gold nanorod solution: Weigh 0.3645 g of cetyltrimethylammonium bromide and dissolve it in 10 mL of ultrapure water. Then add 100 μL of chloroauric acid solution with a mass fraction of 1 wt% to the solution and stir vigorously. Add 0.6 mL of sodium borohydride solution with a concentration of 0.01 M and continue stirring for 2 min until the solution turns brownish-yellow. After stopping stirring, age it at 30 °C for 30 min to obtain gold seed solution.
[0032] (2) Subsequently, 1.4 g of cetyltrimethylammonium bromide and 0.2468 g of sodium oleate were weighed and dissolved in 50 mL of ultrapure water at 50 °C. After cooling the solution to 30 °C, 2.4 mL of 4 mM silver nitrate solution was added, followed by 50 mL of 1 mM chloroauric acid solution while stirring vigorously. After mixing thoroughly, the solution was allowed to stand at 30 °C for 15 min, then stirred at 100 rpm for 90 min. 420 μL of concentrated hydrochloric acid was added dropwise to adjust the temperature. Adjust the pH to 1.4, then stir at 100 rpm for 15 min. Add 0.25 mL of 0.064 M ascorbic acid solution, stir vigorously for 30 s, then add 0.15 mL of pre-prepared gold seed solution, continue stirring for 30 s, and let stand at 30 °C for 12 h. Centrifuge the solution at 9000 rpm for 20 min, wash three times with ultrapure water, and dissolve the resulting solid in 2 mL of ultrapure water to obtain a gold nanorod solution. Figure 1 This is a transmission electron microscope (TEM) image of gold nanorods. From... Figure 1 The gold nanorods clearly show a uniform rod-shaped structure.
[0033] (3) Preparation of gold nanorod@bovine serum albumin solution: Weigh 8 mg of bovine serum albumin and dissolve it in 4 mL of the gold nanorod solution prepared in the above steps. Stir for 30 min. After the bovine serum albumin is completely dissolved, react the solution at 4 °C for 12 h. Figure 2 This is a transmission electron microscope (TEM) image of gold nanorods@bovine serum albumin. (Source: [Insert image here]) Figure 2 It can be clearly seen that gold nanorods@bovine serum albumin also exhibit a uniform rod-shaped structure. However, the difference is that the gold nanorods bound to bovine serum albumin have better dispersibility and are less prone to aggregation.
[0034] Bovine serum albumin, gold nanorods, and gold nanorods@bovine serum albumin were characterized by visible absorption spectroscopy, respectively. The results are as follows: Figure 3 As shown in the figure, bovine serum albumin (BSA) did not exhibit a characteristic absorption peak. The absorption peak of gold nanorods at 518 nm is the transverse plasmon resonance peak, representing the horizontal axis of the gold nanorods, while the absorption peak at 711 nm is the longitudinal plasmon absorption peak, representing the vertical axis of the gold nanorods. The discrepancy between the horizontal and vertical axes of the gold nanorods indirectly confirms their rod-like structure. It is easy to see that the transverse plasmon absorption peak of gold nanorods@bovine serum albumin is at 518 nm, and the longitudinal plasmon absorption peak is at 716 nm. Compared with gold nanorods, the transverse plasmon absorption peak of gold nanorods@bovine serum albumin remains unchanged, while the longitudinal plasmon absorption peak is red-shifted by 5 nm. This is because BSA binds to the gold nanorods through gold-sulfur bonds, causing a change in the refractive index of the gold nanorods, proving the successful synthesis of gold nanorods@bovine serum albumin.
[0035] To further demonstrate the interaction between bovine serum albumin and gold nanorods, X-ray photoelectron spectroscopy analysis was performed, and the results are as follows: Figure 4-6 .like Figure 4 As shown, the X-ray photoelectron spectroscopy of gold nanorods@bovine serum albumin revealed the presence of Au4f (83.8 eV), S2p (163.4 eV), C1s (284.6 eV), N1s (399.7 eV), and O1s (532.0 eV). Figure 5 The high-resolution spectrum of Au4f is shown, with the characteristic peaks at 83.7 and 87.4 eV attributed to Au4f, respectively. 7 / 2 and Au4f 5 / 2 This indicates that the primary valence state of Au is 0. For example... Figure 6 This is a high-resolution spectrum of S2p, with the characteristic peaks at 163.6 and 164.5 eV attributed to S2p, respectively. 3 / 2 and S2p 1 / 2 The characteristic peak at 163.6 eV indicates that gold nanorods and bovine serum albumin formed gold-sulfur bonds, further demonstrating the successful synthesis of gold nanorods@bovine serum albumin.
[0036] Example 2:
[0037] (1) Preparation of gold nanorod solution: Weigh 0.2 g of cetyltrimethylammonium bromide and dissolve it in 10 mL of ultrapure water. Then add 50 μL of chloroauric acid solution with a mass fraction of 1 wt% to the solution and stir vigorously. Add 0.3 mL of sodium borohydride solution with a concentration of 0.02 M and continue stirring for 2 min until the solution turns brownish-yellow. After stopping stirring, age at 30 °C for 30 min to obtain gold seed solution.
[0038] (2) Subsequently, 1.2 g of hexadecyltrimethylammonium bromide and 0.1 g of sodium oleate were weighed and dissolved in 50 mL of ultrapure water at 50 °C. After cooling the solution to 30 °C, 3 mL of 1 mM silver nitrate solution was added. Then, while stirring vigorously, 50 mL of 0.5 mM chloroauric acid solution was added. After mixing evenly, the solution was allowed to stand at 30 °C for 15 min. Then, the solution was stirred at 100 rpm for 90 min. 300 μL of concentrated hydrochloric acid was added dropwise to adjust the pH to 1.4. Then, the solution was stirred at 100 rpm for 15 min. 0.1 mL of 0.03 M ascorbic acid solution was added. The solution was stirred vigorously for 30 s. Then, 0.15 mL of the pre-prepared gold seed solution was added. The solution was stirred for another 30 s. The solution was allowed to stand at 30 °C for 12 h. The solution was centrifuged at 9000 rpm for 20 min. After washing three times with ultrapure water, the resulting solid was dissolved in 2 mL of ultrapure water to obtain a gold nanorod solution.
[0039] (3) Preparation of gold nanorod@bovine serum albumin solution: Weigh 6 mg of bovine serum albumin and dissolve it in 2 mL of the gold nanorod solution prepared in the above steps. Stir for 30 min and after the bovine serum albumin is completely dissolved, react the solution at 4 °C for 12 h.
[0040] Example 3:
[0041] (1) Preparation of gold nanorod solution: Weigh 0.5 g of cetyltrimethylammonium bromide and dissolve it in 10 mL of ultrapure water. Then add 150 μL of chloroauric acid solution with a mass fraction of 1 wt% to the solution and stir vigorously. Add 0.8 mL of sodium borohydride solution with a concentration of 0.03 M and continue stirring for 2 min until the solution turns brownish-yellow. After stopping stirring, age at 30 °C for 30 min to obtain gold seed solution.
[0042] (2) Subsequently, 1.6 g of cetyltrimethylammonium bromide and 0.4 g of sodium oleate were weighed and dissolved in 50 mL of ultrapure water at 50 °C. After cooling the solution to 30 °C, 5 mL of 5 mM silver nitrate solution was added. Then, while stirring vigorously, 50 mL of 2.5 mM chloroauric acid solution was added. After mixing evenly, the solution was allowed to stand at 30 °C for 15 min. Then, the solution was stirred at 100 rpm for 90 min. 500 μL of concentrated hydrochloric acid was added dropwise to adjust the pH to 1.4. Then, the solution was stirred at 100 rpm for 15 min. 0.4 mL of 0.09 M ascorbic acid solution was added. The solution was stirred vigorously for 30 s. Then, 0.15 mL of the pre-prepared gold seed solution was added. The solution was stirred for another 30 s. The solution was allowed to stand at 30 °C for 12 h. The solution was centrifuged at 9000 rpm for 20 min. After washing three times with ultrapure water, the resulting solid was dissolved in 2 mL of ultrapure water to obtain a gold nanorod solution.
[0043] (3) Preparation of gold nanorod@bovine serum albumin solution: Weigh 10 mg of bovine serum albumin and dissolve it in 8 mL of the gold nanorod solution prepared in the above steps. Stir for 30 min and after the bovine serum albumin is completely dissolved, react the solution at 4 °C for 12 h.
[0044] Example 4:
[0045] Temperature difference identification of Trp enantiomers: 0.8 mL of the gold nanorod@bovine serum albumin solution prepared in Example 1 was mixed with an equal volume of Trp enantiomer solution, and then transferred to a 2 mL centrifuge tube. After stirring thoroughly, a thermometer was inserted into the solution. A 1 W near-infrared laser with a wavelength of 808 nm was used to irradiate the solution in the centrifuge tube. Starting from 0 s, the thermometer was observed every 5 min, and the real-time temperature was recorded. A total of 7 records were made over a period of 30 min. The temperature difference (T) between the two enantiomers was calculated. D-Trp-T L-Trp To evaluate the efficiency of chirality recognition.
[0046] The gold nanorods@bovine serum albumin temperature difference recognition Trp enantiomers described in this invention are identified using the following method:
[0047] ΔT=T D-Trp -T L-Trp
[0048] In the formula, ΔT represents the temperature difference after the gold nanorods@bovine serum albumin bind to the amino acid enantiomers, and T D-Trp and T L-Trp The values represent the temperatures at which gold nanorods@bovine serum albumin bind to D-tryptophan and L-tryptophan, respectively.
[0049] like Figure 7 As shown, the temperature difference after gold nanorods@bovine serum albumin binds to 5 mM L- / D-Trp is 7 °C. This is attributed to the fact that bovine serum albumin binds to L-Trp more readily, allowing gold nanorods@bovine serum albumin to bind more L-Trp that do not have photothermal conversion properties. Consequently, the temperature rise of gold nanorods@bovine serum albumin bound to L-Trp under near-infrared light irradiation is lower than that of gold nanorods@bovine serum albumin bound to D-Trp under near-infrared light irradiation.
Claims
1. A chiral sensor for gold nanorods@bovine serum albumin that enables chiral recognition via temperature difference, characterized in that, A gold nanorod solution was prepared using a seed growth method, and bovine serum albumin was bound to the gold nanorods via gold-sulfur bonds to obtain a gold nanorod@bovine serum albumin chiral sensor. The gold nanorod@bovine serum albumin chiral sensor is used to bind to amino acid enantiomers and achieve chiral recognition of amino acid enantiomers by means of the temperature difference generated by the difference in chiral recognition ability under near-infrared light irradiation.
2. The method for preparing a gold nanorod@bovine serum albumin chiral sensor that can achieve chiral recognition via temperature difference as described in claim 1, characterized in that, Includes the following steps: (1) A gold nanorod solution was prepared by seed growth method; (2) Weigh bovine serum albumin and dissolve it in the gold nanorod solution obtained in step (1). Stir and, after the bovine serum albumin is completely dissolved, place it in an environment at 4°C for reaction.
3. The preparation method according to claim 2, characterized in that, The specific method for preparing the gold nanorod solution using the seed growth method in step (1) is as follows: (a) Weigh hexadecyltrimethylammonium bromide and dissolve it in ultrapure water. Add 0.5~1.5wt% chloroauric acid solution, stir vigorously, add sodium borohydride solution, and continue stirring until it turns brownish-yellow. Stop stirring and age the solution to obtain the gold seed solution. (b) Weigh hexadecyltrimethylammonium bromide and sodium oleate, dissolve them in ultrapure water at 40-60°C, cool to 20-40°C, add silver nitrate solution, and add chloroauric acid solution while stirring vigorously. After mixing evenly, let stand, stir for the first time, add concentrated hydrochloric acid dropwise to adjust the pH to 1-2, stir for the second time, add ascorbic acid solution, and stir vigorously for 20-40 seconds. (c) Add the gold seed solution, continue stirring for 20-40 seconds, let stand, centrifuge, wash several times with ultrapure water, take the precipitate and dissolve it in ultrapure water to obtain a gold nanorod solution.
4. The preparation method according to claim 3, characterized in that, In step (a), the mass-to-volume ratio of hexadecyltrimethylammonium bromide, chloroauric acid solution, and sodium borohydride solution is 0.2-0.5 g: 50-150 µL: 0.3-0.8 mL; the concentration of the sodium borohydride solution is 0.01-0.03 M; the mass-to-volume ratio of hexadecyltrimethylammonium bromide to ultrapure water is 0.2-0.5 g: 10 mL; and the aging conditions are: temperature 20-40 °C, time 15-40 min.
5. The preparation method according to claim 3, characterized in that, In step (b), the mass-to-volume ratio of hexadecyltrimethylammonium bromide, sodium oleate, and ultrapure water is 1.2-1.6 g: 0.1-0.4 g: 50 mL; the volume ratio of hexadecyltrimethylammonium bromide, silver nitrate solution, chloroauric acid solution, concentrated hydrochloric acid, ascorbic acid solution, and gold seed solution is 1.2-1.6 g: 2-5 mL: 50 mL: 300-500 µL: 0.1-0.4 mL: 0.15 mL; the concentration of silver nitrate is 1-5 mM, the concentration of chloroauric acid is 0.5-2.5 mM, and the concentration of ascorbic acid is 0.03-0.09 M.
6. The preparation method according to claim 3, characterized in that, The conditions for settling in step (b) are: temperature 20~40℃, time 10~30min; the conditions for the first stirring are: speed 50~150rpm, time 60~120min; the conditions for the second stirring are: speed 50~150rpm, time 10~30min.
7. The preparation method according to claim 3, characterized in that, The conditions for settling in step (c) are: temperature 20~40℃, time 10~14h; the conditions for centrifugation are: speed 8000~10000rpm, time 10~30min.
8. The preparation method according to claim 2, characterized in that, In step (2), the mass-to-volume ratio of bovine serum albumin to gold nanorod solution is 6-10 mg: 2-8 mL; the reaction time is 10-14 h.
9. The use of the gold nanorod@bovine serum albumin chiral sensor as described in claim 1 in the chiral recognition of amino acid enantiomers using temperature difference.
10. The use as described in claim 9, characterized in that, The amino acid includes Trp.