Medical gauze

Abstract

To provide a medical gauze capable of increasing an amount of bacterial attachment.SOLUTION: A medical gauze according to an embodiment includes a gauze body and a cello-oligosaccharide having, at the anomeric position of a reducing end, a substituent containing an alkyl group having 5 or more carbon atoms, the cello-oligosaccharide being immobilized on the gauze body.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to medical gauze. [Background technology]

[0002] Medical gauze is used in wound treatment and surgery to control bleeding, absorb body fluids, protect from trauma, etc. Here, gauze is generally made of coarse, soft cotton cloth, but is not limited to this and may also be made of non-woven fabrics such as non-woven gauze.

[0003] It is known that crystalline cellulose can be artificially synthesized. The cellulose obtained by artificial synthesis is generally an oligomer called cellooligosaccharide. Patent Document 1 discloses cellooligosaccharides in which an alkyl group has been introduced as a substituent at the anomeric position of the reducing end, and proposes that aggregates of such cellooligosaccharides be used as scaffolds for cell culture, films, battery separators, and the like. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2016 / 113933 Summary of the Invention [Problem to be solved by the invention]

[0005] While investigating new uses for the cellooligosaccharides, the present inventors discovered that immobilizing cellooligosaccharides on gauze increases the amount of bacteria that adheres to it.

[0006] The embodiments of the present invention have been made in view of the above points, and have an object to provide medical gauze that can increase the amount of bacteria attached. [Means for solving the problem]

[0007] The present invention includes the embodiments shown below. [1] A medical gauze comprising a gauze body and a cellooligosaccharide having a substituent containing an alkyl group having 5 or more carbon atoms at the anomeric position of the reducing end and immobilized on the gauze body. [2] The cellooligosaccharide is represented by the following general formula (1): [ka] In the formula, n is an average degree of polymerization and represents a number of 5 to 20, and m is an integer of 5 or more. [3] A medical gauze according to [1] or [2], in which the cellooligosaccharide is immobilized on the gauze body by precipitating it in the presence of the gauze body. [4] The medical gauze according to any one of [1] to [3], which is used to cover a wound surface. [Effects of the Invention]

[0008] According to an embodiment of the present invention, the amount of bacteria that can adhere can be increased by immobilizing cellooligosaccharides having a substituent that includes an alkyl group having 5 or more carbon atoms on the gauze body. [Brief explanation of the drawings]

[0009] [Figure 1] Cross-sectional schematic diagram of cellooligosaccharide aggregates. [Figure 2] Conceptual diagram of a cellulose nanosheet, an example of a cellooligosaccharide assembly. [Figure 3] Graphs showing the quantitative results of bacterial adhesion amounts in Test Example 1, where (A) shows the results for the unmodified cellooligosaccharide (CEL-OH) of Comparative Example 1, (B) shows the results for the ethylated cellooligosaccharide (CEL-C2) of Comparative Example 2, (C) shows the results for the butylated cellooligosaccharide (CEL-C4) of Comparative Example 3, and (D) shows the results for the hexylated cellooligosaccharide (CEL-C6) of Example 1. [Figure 4]Scanning electron microscope (SEM) image of the CEL-C6 composite gauze of Example 1. [Figure 5] Graphs showing the quantitative results of bacterial adhesion in Test Example 2, where (A) shows the results for the unmodified cellooligosaccharide (CEL-OH) of Comparative Example 4, (B) shows the results for the hexylated cellooligosaccharide (CEL-C6) of Example 2, and (C) shows the results for the octylated cellooligosaccharide (CEL-C8) of Example 3. [Figure 6] Scanning electron microscope (SEM) image of the CEL-C6 composite gauze of Example 2. DETAILED DESCRIPTION OF THE INVENTION

[0010] The medical gauze according to this embodiment (hereinafter also referred to simply as "gauze") comprises a gauze body and a cellooligosaccharide having a substituent containing an alkyl group having 5 or more carbon atoms at the anomeric position of the reducing end and immobilized on the gauze body.

[0011] In this specification, the gauze body is not limited to cotton fabric in the strict sense of the term, but may be a woven fabric, knitted fabric, or nonwoven fabric. Furthermore, the material is not limited to cotton, but may be other cellulose fibers such as hemp, natural fibers other than cellulose fibers, or synthetic fibers such as polyester fibers. Preferably, the gauze body is primarily made of cellulose fibers, for example, containing 50% by mass or more of cellulose fibers, more preferably made of cellulose fibers, and even more preferably made of cotton. Ordinary coarse, soft cotton fabric may also be used.

[0012] Cellooligosaccharides are oligosaccharides with a structure in which glucose units are linked by β-1,4-glycosidic bonds, and are also called cellulose oligomers. In this embodiment, a cellooligosaccharide in which a substituent containing an alkyl group is introduced at the anomeric position of the reducing end (hereinafter referred to as "alkylated cellooligosaccharide") is used.

[0013] In this embodiment, the alkyl group introduced at the anomeric position of the alkylated cellooligosaccharide has 5 or more carbon atoms. As shown in the examples below, gauze to which cellooligosaccharides have been immobilized exhibits greater bacterial adhesion in the presence of serum than uncomplexed gauze to which no cellooligosaccharides have been immobilized. However, in the absence of serum, bacteria adhere less readily to gauze to which unmodified cellooligosaccharides have been immobilized than to uncomplexed gauze. In contrast, gauze to which alkylated cellooligosaccharides having a substituent containing an alkyl group with 5 or more carbon atoms have increased bacterial adhesion compared to uncomplexed gauze, not only in the presence of serum but also in the absence of serum. Although the reason for this is unclear, it is thought that the increased carbon number of the alkyl group increases hydrophobicity, which facilitates bacterial adhesion.

[0014] In this way, bacteria can be more easily attached to the gauze, which in turn can suppress bacterial adhesion to the wound surface. According to this embodiment, the amount of bacteria attached increases compared to non-composite gauze not only in the presence of serum but also in the absence of serum, so that the amount of bacteria on the wound surface can be reduced not only in the early stage of the wound but also in the late stage when the wound surface is almost dry.

[0015] The upper limit of the number of carbon atoms in the alkyl group in the alkylated cellooligosaccharide is not particularly limited, but from the viewpoints of ease of obtaining the primer described below and ease of control of self-assembly, the upper limit is preferably 30. The number of carbon atoms in the alkyl group is preferably 5 to 30, more preferably 5 to 20, more preferably 5 to 12, more preferably 6 to 10, and even more preferably 6 to 8. The alkyl group may be linear or branched. The alkyl group is preferably a linear alkyl group.

[0016] The average degree of polymerization (DP) of alkylated cellooligosaccharides (the average number of glucose units present in one molecule) is not particularly limited, but is preferably 5 to 20. The average degree of polymerization (DP) is more preferably 6 to 16, more preferably 6 to 10, and even more preferably 7 to 9. The average degree of polymerization of alkylated cellooligosaccharides is a weighted average of the degrees of polymerization according to the mass ratio of the alkylated cellooligosaccharides. Alkylated cellooligosaccharides are usually a mixture of compounds with different degrees of polymerization, and may include, for example, those with a degree of polymerization of 4 to 20, or those with a degree of polymerization of 5 to 18.

[0017] As the alkylated cellooligosaccharide, it is preferable to use a compound represented by the following general formula (1). [ka]

[0018] In formula (1), an alkyl group as a substituent is bonded to the anomeric position, i.e., the carbon at position 1 (anomeric carbon) of the reducing end, via an oxygen atom. The wavy line in the bond between the anomeric carbon and the alkoxy group in formula (1) indicates that the alkoxy group has an α-configuration, a β-configuration, or a mixture of α- and β-configurations. The β-configuration of the alkoxy group is preferred.

[0019] In formula (1), n ​​represents the average degree of polymerization of cellooligosaccharides, and is preferably 5 to 20, more preferably 6 to 16, more preferably 6 to 10, and even more preferably 7 to 9, as described above.

[0020] In formula (1), m represents the number of carbon atoms in the alkyl group, and is an integer of 5 or more, as described above, preferably 5 to 30, more preferably 5 to 20, more preferably 5 to 12, more preferably 6 to 10, and even more preferably 6 to 8. The alkyl group may be linear or branched, as described above. Specific preferred examples of the alkyl group include linear alkyl groups such as n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, and n-tetradecyl.

[0021] The method for preparing alkylated cellooligosaccharides is not particularly limited. For example, alkylated cellooligosaccharides may be prepared by an enzymatic synthesis reaction utilizing the reverse reaction of cellodextrin phosphorylase (CDP) (see Y. Yataka et al., Langmuir, 2016, 32, 10120-10125).

[0022] Specifically, in the enzymatic synthesis reaction, α-glucose-1-phosphate (αG1P) and alkyl-β-D-glucopyranoside are reacted with CDP, whereby αG1P is sequentially polymerized as a monomer with the alkyl-β-D-glucopyranoside as a primer to obtain the alkylated cellooligosaccharide represented by formula (1).

[0023] CDP is known to be produced by microorganisms such as Clostridium thermocellum and Cellulomonas, and can be obtained by known methods using these microorganisms. For example, CDP derived from Clostridium thermocellum YM4 can be prepared in an Escherichia coli expression system according to the method described in M. Krishnareddy et al., J. Appl. Glycosci., 2002, 49, 1-8, but is not limited thereto.

[0024] The concentration of CDP is not particularly limited and may be, for example, 0.1 U / mL or more, or 0.2 U / mL or more. Here, the amount of CDP enzyme can be determined, for example, based on the enzyme activity. For example, αG1P, D-(+)-cellobiose, and CDP are incubated, the amount of phosphate produced by CDP is quantified, and the amount of enzyme that liberates 1 μmol of phosphate per minute can be defined as 1 U.

[0025] For example, alkylated cellooligosaccharides of formula (1) can be synthesized by mixing 10-1000 mM αG1P, 10-200 mM alkyl-β-D-glucoside, and 0.1 U / mL or more of CDP in 100-1000 mM 2-[4-(2-hydroxyethyl)-1-piperazinyl]ethanesulfonic acid (HEPES) buffer (pH 7.0-8.0) and incubating at 10-80°C for 30 minutes to 30 days. Here, "M" stands for molar concentration (mol / L), and therefore "mM" stands for "mmol / L."

[0026] The alkylated cellooligosaccharides may be immobilized (complexed) to the gauze body as self-assembled aggregates. Preferably, the alkylated cellooligosaccharides are immobilized to the gauze body by precipitation in the presence of the gauze body. The alkylated cellooligosaccharides immobilized in this manner are cellooligosaccharide aggregates having the crystalline structure of cellulose type I (type 1) or cellulose type II (type 2), preferably aggregates having the crystalline structure of cellulose type II.

[0027] The crystalline structure of cellulose type I is similar to that of naturally occurring cellulose, in that adjacent chains are oriented in the same direction, whereas the crystalline structure of cellulose type II is such that adjacent chains are oriented in opposite directions.

[0028] Specifically, the alkylated cellooligosaccharides are represented by arrows pointing from the reducing end to the non-reducing end of the cellulose chain, and the substituents containing alkyl groups are represented by wavy lines, as shown below in formula (1). In the crystalline structure of cellulose type II, the alkylated cellooligosaccharides are arranged so that the arrows point alternately between adjacent molecular chains, as shown in Figure 1.

[0029] In one embodiment, the cellooligosaccharide aggregate having a cellulose type II crystalline structure may have a sheet-like structure (cellulose nanosheet) consisting of a monolayer, as shown in Figure 2. Here, the sheet-like structure is a concept that encompasses ribbon-like structures (cellulose nanoribbons) as shown in Figure 2. Such nanoribbons may be immobilized in a network form on the fiber surface of the gauze body. Alternatively, the cellooligosaccharide aggregate may be immobilized in the form of small crystal protrusions on the fiber surface of the gauze body without forming a noticeable sheet-like structure.

[0030] The method for immobilizing the alkylated cellooligosaccharides as cellooligosaccharide aggregates on the gauze bodies by precipitating them in the presence of the gauze bodies is not particularly limited. For example, alkylated cellooligosaccharides may be obtained by the above-mentioned enzymatic synthesis reaction and then incubated in the presence of the gauze bodies to precipitate the cellooligosaccharide aggregates and immobilize them on the gauze bodies. Alternatively, the alkylated cellooligosaccharides obtained by the enzymatic synthesis reaction may be dissolved in alkali and then neutralized with acid to precipitate the cellooligosaccharide aggregates in the presence of the gauze bodies and immobilize them on the gauze bodies (hereinafter, this immobilization method is referred to as neutralization-induced precipitation immobilization). Alternatively, the alkylated cellooligosaccharides obtained by the enzymatic synthesis reaction may be dissolved in phosphoric acid and then water may be added to precipitate the cellooligosaccharide aggregates in the presence of the gauze bodies and immobilize them on the gauze bodies (hereinafter, this immobilization method is referred to as phosphoric acid precipitation immobilization).

[0031] In the medical gauze according to this embodiment, the amount of alkylated cellooligosaccharide immobilized on the gauze body is not particularly limited, and is preferably 0.1 to 200 parts by mass, more preferably 1 to 50 parts by mass, and even more preferably 5 to 20 parts by mass, per 100 parts by mass of the gauze body.

[0032] The medical gauze according to this embodiment may be composed of only the gauze body and alkylated cellooligosaccharides, but may also contain, for example, an antibacterial agent or silver nanoparticles, as long as the effect is not impaired.

[0033] The medical gauze according to this embodiment can be used in wound treatment and surgery, for example, to suppress bleeding, absorb body fluids, and protect from trauma. It is preferably used to cover the wound surface, and is used as a wound dressing for suppressing bleeding from the wound surface and protecting the wound surface, for example, as a bandage pad. Alternatively, the medical gauze can be used, for example, as a mask.

[0034] The medical gauze according to this embodiment has excellent bacterial adhesion properties, so it can adsorb bacteria from the wound surface and suppress bacterial proliferation on the wound surface. Furthermore, as described above, the amount of bacteria adhered to the gauze increases not only in the presence of serum but also in the absence of serum, compared to uncomplexed gauze. Therefore, the amount of bacteria on the wound surface can be reduced not only in the early stage of the wound but also in the late stage when the wound surface is almost dry. [Example]

[0035] The present invention will be further explained below with reference to examples, but is not limited to these.

[0036] [Synthesis of hexylated cellooligosaccharides] According to the method described in Y. Yataka et al., Langmuir, 2016, 32, 10120-10125, enzyme-catalyzed polymerization was carried out according to the following reaction scheme to synthesize hexylated cellooligosaccharides with an average degree of polymerization of 7 (n=7). [ka]

[0037] Specifically, 200 mmol / L αG1P, 50 mmol / L hexyl-β-D-glucopyranoside, and 0.2 U / mL cellodextrin phosphorylase (CDP) were mixed in 500 mmol / L 2-[4-(2-hydroxyethyl)-1-piperazinyl]ethanesulfonic acid (HEPES) buffer (pH 7.5) and incubated at 60°C for 3 days. The reaction mixture containing the product was centrifuged (15,000 rpm, 10 min or more, 4°C). The supernatant was removed, and the product was redispersed in ultrapure water. This procedure was repeated under the same conditions to obtain hexylated cellooligosaccharide (CEL-C6). The supernatant was then purified to a substitution rate of 99.999% or higher.

[0038] [Synthesis of other cellooligosaccharides] Ethylated cellooligosaccharides bearing OC2H5 at the anomeric position of the reducing end (CEL-C2) were synthesized in the same manner as hexyl-β-D-glucopyranoside, except that ethyl-β-D-glucopyranoside was used instead of hexyl-β-D-glucopyranoside. The average degree of polymerization was 7 (n=7).

[0039] Butylated cellooligosaccharides bearing OC4H8 at the anomeric reducing end were synthesized in the same manner as for hexyl cellooligosaccharides, except that butyl-β-D-glucopyranoside was used instead of hexyl-β-D-glucopyranoside. The average degree of polymerization was 7 (n=7).

[0040] Instead of hexyl-β-D-glucopyranoside, octyl-β-D-glucopyranoside was used, and the other conditions were the same as for hexylated cellooligosaccharides. 17 Octylated cellooligosaccharides (CEL-C8) with an average degree of polymerization of 7 (n=7) were synthesized.

[0041] Unmodified cellooligosaccharides (CEL-OH) without reducing end OH substituents were synthesized in the same manner as hexyl-β-D-glucopyranoside, except that D-glucopyranoside was used instead of hexyl-β-D-glucopyranoside. The average degree of polymerization was 7 (n=7).

[0042] The average degree of polymerization of cellooligosaccharides was measured using a proton nuclear magnetic resonance (NMR) spectrometer. Specifically, 12 mg or more of the freeze-dried product was dissolved in 600 μL of 4% by mass sodium deuterium hydroxide deuterium oxide solution to prepare a measurement sample. The NMR spectrometer used was an ADVANCE III HD500 (Bruker Biospin, magnetic field strength: 500 MHz, number of accumulations: 16). The average degree of polymerization was calculated based on the integral values ​​of the protons at the anomeric position of the reducing end of the cellooligosaccharide and at other anomeric positions.

[0043] [Test Example 1: Phosphoric Acid Precipitation Immobilization] Example 1: CEL-C6 composite gauze ·Complexation of gauze with cellooligosaccharides: To the freeze-dried hexylated cellooligosaccharide (CEL-C6), an 85% by mass aqueous solution of phosphoric acid was added so that the concentration of hexylated cellooligosaccharide became 2% (w / v), and the hexylated cellooligosaccharide was dissolved. 30 μL of the resulting solution and 30 μL of sterile purified water were added to a 1.5 mL tube and immediately mixed by pipetting. A 1 cm square piece of gauze (Osaki Medical Co., Ltd., "Cross Gauze Cotton No. 6", basis weight: approximately 36 g / m) was placed in a Petri dish. 2 , 100% cotton) was placed in a container, to which 60 μL of the above-mentioned pipetted aqueous solution (cellooligosaccharide concentration 1% (w / v), phosphoric acid concentration 42.5% by mass) was added, and the container was left to stand at room temperature for 2 hours. As a result, CEL-C6 was precipitated by self-assembly and immobilized on the gauze, yielding CEL-C6-composite gauze. Here, "% (w / v)" is the mass-volume percent concentration, which is the mass (g) of the target substance contained in a volume of 100 mL.

[0044] ·purification: The CEL-C6 composite gauze obtained above was placed in a 9 cm Petri dish, and sterilized purified water was added so that the gauze was completely immersed. The gauze was left to stand at room temperature for 1 hour, and then the sterilized purified water was removed. This procedure was repeated five times, and the CEL-C6 composite gauze was then immersed in D-PBS(-) for 12 hours.

[0045] After purification, the morphology of the CEL-C6 composite gauze was observed using a scanning electron microscope (SEM) at magnifications of 10,000x and 40,000x. As shown in Figure 4, the CEL-C6 aggregates did not form a noticeable sheet-like structure, but were fixed as small crystal protrusions on the surface of the cellulose fibers in the gauze body.

[0046] E. coli adhesion treatment: 1 x 10 cells in a 3.5 cm dish 7 Three milliliters of a D-PBS(-) solution of E. coli (ER2738 strain, obtained from New England Biolabs) containing colony-forming units (CFU) / mL was added. The CEL-C6 composite gauze soaked in the purified PBS solution was placed on an autoclave-sterilized paper towel (Kimtowel, manufactured by Nippon Paper Crecia Co., Ltd.) for 5 seconds to absorb water, then placed in a petri dish, immersed in the E. coli / PBS solution, and allowed to stand (incubate) at 37°C for 24 hours.

[0047] The E. coli / PBS solution used was one without added FBS (fetal bovine serum, obtained from Biowest) (0% by mass) and one with added FBS at a concentration of 1% or 10% by mass, and each solution was subjected to an attachment treatment. As a control, uncomplexed gauze prepared in the same manner as the CEL-C6-complexed gauze, but without CEL-C6, was also subjected to an E. coli attachment treatment in the same manner as the CEL-C6-complexed gauze. In Figure 3, gauze complexed with cellooligosaccharide (CEL-C6) is labeled "nano," and uncomplexed gauze is labeled "(-)." The same applies to Comparative Examples 1 to 3, which will be described later.

[0048] Washing: To remove any E. coli bacteria that had not adhered to the gauze after incubation, the gauze was placed in a 3 cm Petri dish together with 3 mL of D-PBS(-) and shaken for 30 minutes (using a small desktop shaker "Wave-RP" manufactured by Taitec Corporation, shaking speed: speed 40). This process was repeated twice.

[0049] Quantification of E. coli: One mL of D-PBS(-) solution was added to a 1.5 mL tube, and a washed gauze was placed inside. Then, the tube was sonicated (25°C, 40 kHz) for 5 minutes to detach the E. coli from the gauze. The PBS solution containing the detached E. coli was serially diluted with D-PBS(-) solution, and 1 mL of the diluted solution was added dropwise to a medium (Shimadzu Diagnostics Co., Ltd., "Compact Dry TC") and incubated at 35°C for 2 days. After incubation, the number of colonies was counted.

[0050] (Comparative Example 1: CEL-OH composite gauze) Using unmodified cellooligosaccharide (CEL-OH) instead of CEL-C6, gauze was conjugated with cellooligosaccharide in the same manner as in Example 1 to prepare CEL-OH conjugated gauze, which was then purified, treated with E. coli, washed, and the E. coli was quantified.

[0051] (Comparative Example 2: CEL-C2 composite gauze) Using ethylated cellooligosaccharide (CEL-C2) instead of CEL-C6, gauze was complexed with cellooligosaccharide in the same manner as in Example 1 to prepare CEL-C2 complexed gauze, which was then purified, treated to attach E. coli, washed, and quantified.

[0052] (Comparative Example 3: CEL-C4 composite gauze) Using butylated cellooligosaccharide (CEL-C4) instead of CEL-C6, gauze was complexed with cellooligosaccharide in the same manner as in Example 1 to prepare CEL-C4 complexed gauze, which was then purified, treated to attach E. coli, washed, and quantified.

[0053] The quantification results of E. coli for Example 1 and Comparative Examples 1 to 3 are shown in Figure 3. As shown in Figure 3(A), the amount of E. coli attached to the CEL-OH composite gauze of Comparative Example 1 was greater in the presence of serum (FBS) than to the uncomposite gauze (-). However, in the absence of serum (0% by mass of FBS), the amount of E. coli attached to the CEL-OH composite gauze was less than that of the uncomposite gauze.

[0054] For the CEL-C2 composite gauze of Comparative Example 2 shown in Figure 3(B) and the CEL-C4 composite gauze of Comparative Example 3 shown in Figure 3(C), the amount of E. coli attached was equal to or greater than that of the uncomposite gauze (-) in the presence of serum (FBS), but was less than that of the uncomposite gauze in the absence of serum.

[0055] In contrast, the CEL-C6 composite gauze of Example 1 shown in Figure 3(D) not only had a greater amount of E. coli attached to it than the uncomposite gauze (-) in the presence of serum, but also had a greater amount of E. coli attached to it than the uncomposite gauze in the absence of serum.

[0056] [Test Example 2: Neutralization-induced precipitation fixation] Example 2: CEL-C6 composite gauze ·Complexation of gauze with cellooligosaccharides: A 1 mol / L aqueous solution of sodium hydroxide was added to the freeze-dried hexylated cellooligosaccharide (CEL-C6) so that the concentration of the hexylated cellooligosaccharide became 2% (w / v), and the hexylated cellooligosaccharide was dissolved. The resulting solution was left to stand at -20°C for 20 minutes and then thawed at 25°C. A 1 cm square piece of gauze (Osaki Medical Co., Ltd., "Cross Gauze Cotton No. 6", basis weight: approximately 36 g / m) was placed in a Petri dish. 2A 100% cotton gauze was placed in the gauze, and 30 μL of the melted cellooligosaccharide solution (2% (w / v)) was added. 30 μL of 1 mol / L hydrochloric acid / 0.1 mol / L phosphate buffer solution was then added. The gauze was left to stand at room temperature for 2 hours to precipitate hexylated cellooligosaccharides by self-assembly. The final concentrations of cellooligosaccharides and NaCl were 1% (w / v) and 0.5 mol / L, respectively. This immobilized CEL-C6 on the gauze, yielding a CEL-C6 conjugated gauze.

[0057] ·purification: The CEL-C6 composite gauze obtained above was placed in a 9 cm Petri dish, and sterilized purified water was added so that the gauze was completely immersed. The gauze was left to stand at room temperature for 1 hour, and then the sterilized purified water was removed. This procedure was repeated five times, and the CEL-C6 composite gauze was then immersed in D-PBS(-) for 12 hours.

[0058] After purification, the morphology of the CEL-C6 composite gauze was observed using a scanning electron microscope (SEM) at magnifications of 10,000x and 40,000x. As shown in Figure 6, the CEL-C6 aggregates were nanoribbon-shaped, and the nanoribbons were fixed in a network-like structure on the surface of the cellulose fibers in the gauze body (nanoribbon network structure).

[0059] E. coli adhesion treatment, cleaning, and E. coli quantification: The CEL-C6 composite gauze obtained by the neutralization-induced precipitation fixation described above was subjected to E. coli attachment treatment, washing, and E. coli quantification in the same manner as in Test Example 1. As in Test Example 1, E. coli / PBS solutions were used, including those without FBS (0% by mass) and those with FBS added to concentrations of 1% by mass or 10% by mass, and E. coli attachment treatment was performed on each. As a control, uncomposite gauze prepared in the same manner as the CEL-C6 composite gauze except without CEL-C6 was also subjected to E. coli attachment treatment in the same manner as the CEL-C6 composite gauze. In Figure 5, gauze composited with cellooligosaccharide (CEL-C6) is indicated as "nano," and uncomposite gauze is indicated as "(-)." The same applies to Example 3 and Comparative Example 4 described below.

[0060] (Example 3: CEL-C8 composite gauze) ·Complexation of gauze with cellooligosaccharides: Gauze was conjugated with cellooligosaccharide in the same manner as in Example 2, except that octylated cellooligosaccharide (CEL-C8) was used instead of CEL-C6, to prepare CEL-C8 conjugated gauze.

[0061] ·purification: The CEL-C8 conjugated gauze obtained above was placed in a 24-well plate. PBS was added so that the gauze was completely immersed. After soaking for 5 minutes, the solution was removed. This procedure was repeated 5 times.

[0062] E. coli adhesion treatment, cleaning, and E. coli quantification: The E. coli adhesion treatment and washing were carried out in the same manner as in Example 2, except that CEL-C8 composite gauze was used instead of CEL-C6 composite gauze, and E. coli (ATCC51813 strain, obtained from Microbiologics) was used instead of E. coli (ER2738 strain, obtained from New England Biolabs). Furthermore, the E. coli quantification was carried out in the same manner as in Example 2, except that Shimadzu Diagnostics' Compact Dry CF was used instead of Shimadzu Diagnostics' Compact Dry TC, and the incubation period was changed from two days to one day.

[0063] (Comparative Example 4: CEL-OH composite gauze) Using unmodified cellooligosaccharide (CEL-OH) instead of CEL-C6, gauze was conjugated with cellooligosaccharide in the same manner as in Example 2 to prepare CEL-OH conjugated gauze, which was then purified, treated to attach E. coli, washed, and quantified.

[0064] The quantification results of E. coli for Examples 2 and 3 and Comparative Example 4 are shown in Figure 5. As shown in Figure 5(A), the amount of E. coli attached to the CEL-OH composite gauze of Comparative Example 4 was greater in the presence of serum (FBS) than that of the uncomposite gauze (-). However, in the absence of serum, the amount of E. coli attached to the CEL-OH composite gauze was less than that of the uncomposite gauze.

[0065] In contrast, the CEL-C6 composite gauze of Example 2 shown in Figure 5(B) not only showed a higher amount of E. coli adhered to it than the uncomposite gauze (-) in the presence of serum, but also showed a higher amount of E. coli adhered to it than the uncomposite gauze in the absence of serum. In the absence of serum, the CEL-C6 composite gauze showed approximately 2.4 times the amount of E. coli adhered to it compared to the uncomposite gauze, demonstrating a higher bacterial adhesion effect than the phosphoric acid precipitated CEL-C6 composite gauze of Example 1.

[0066] As in Example 2, the CEL-C8 composite gauze of Example 3 shown in Figure 5(C) not only had a greater amount of E. coli attached to it than the uncomposite gauze (-) in the presence of serum, but also had a greater amount of E. coli attached to it than the uncomposite gauze in the absence of serum.

[0067] The various numerical ranges described in this specification can be arbitrarily combined with their upper and lower limits, and all such combinations are considered to be preferred numerical ranges described in this specification. Furthermore, a numerical range described as "X to Y" means from X to Y.

[0068] Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their omissions, substitutions, modifications, etc. are included within the scope and spirit of the invention, as well as within the scope of the invention described in the claims and their equivalents.

Claims

1. A medical gauze comprising a gauze body and a cellooligosaccharide having a substituent containing an alkyl group having 5 or more carbon atoms at the anomeric position of the reducing end and immobilized on the gauze body.

2. The cellooligosaccharide is represented by the following general formula (1): 【Chemistry 1】 In the formula, n represents the average degree of polymerization and is a number from 5 to 20, and m represents an integer of 5 or more. The medical gauze according to claim 1.

3. 3. The medical gauze according to claim 1, wherein the cellooligosaccharide is immobilized on the gauze body by precipitation in the presence of the gauze body.

4. 3. The medical gauze according to claim 1, which is used to cover a wound surface.

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