Test groups: adding 2 percent fetal calf serum culture medium leaching liquor according to the proportion of 0.1g/ml of the sample mass, and shaking at the constant temperature of 37 ℃ for 24 +/-1 h.

Digesting cultured cells with vigorous growth for 48-72 h to obtain the cell with density of 1.5 × 10⁴Inoculating the cell suspension of each cell/ml into a 96-well plate, adding 100 mu L of the cell suspension into each well, and placing the cell suspension in 5% CO₂The culture was carried out in an incubator at 37 ℃ for 24 hours.

Discarding the original culture solution, adding 200 μ L negative control solution, positive control solution, and sample solution, placing 5 holes in each group, and placing in 5% CO₂The culture was carried out in an incubator at 37 ℃ for 48 hours. Adding 15 mu LMTT solution and 5% CO into each hole₂Culturing for 4h at 37 ℃ in an incubator, discarding the culture solution, adding 150 mu LDMSO respectively, shaking for 10min, detecting the absorbance at 490nm on an enzyme-labeling instrument, calculating the increment rate, and grading the in-vitro cytotoxicity reaction according to the table 1. The test results are shown in table 2.

TABLE 1 in vitro cytotoxicity response ranking

Toxicity rating (grade)	0	1	2	3	4
						Relative proliferation Rate (%)	≥100	80-99	50-79	30-49	0-29

TABLE 2 in vitro cytotoxicity test results

Sample (I)	2D
			Level 1
	Level 1
		Positive control	4 stage

As can be seen from Table 3, will

Sodium alginate derivatives and

the leaching liquor of the hydrogel dressing is used for culturing cells for 2 days respectively, and the cytotoxicity reaction grading is 1 grade, which shows that the sodium alginate derivative and the hydrogel dressing both have good biocompatibility.

Example five:

the polypeptide modified sodium alginate/PVA hydrogel dressing prepared by the invention is subjected to a bacteriostasis test.

The quantitative bacteriostasis test is carried out according to the carrier soaking method specified in WS/T650-2019.

Washing 24h fresh slant culture of test bacterium Escherichia coli with PBS, and diluting to 5.0 × 10⁶CFU/mL～5.0×10⁷CFU/mL bacterial suspension is ready for use. 10 mul of the bacterial suspension was applied by drop-dyeing to sterilized plain cloth pieces (10 mm. times.10 mm) and dried at 36 ℃. + -. 1 ℃ for use.

Weighing a sample according to the amount of 5 g/piece, placing the sample in a sterile plate, placing the sterile plate in a water bath at 20 +/-1 ℃ for 5min, taking a bacteria-staining cloth piece by using a sterile forceps, completely immersing the cloth piece in the sample, immediately timing, respectively taking out the bacteria-staining cloth piece, placing the bacteria-staining cloth piece into 5.0 mL PBS test tubes after 6 hours of interaction between a bacteria-staining carrier and the sample, uniformly mixing, oscillating, washing test bacteria, respectively absorbing 1.0 mL sample liquid, determining the number of viable bacteria according to a viable bacteria culture counting method, and inoculating 2 plates in each tube of sample liquid. The same batch of PBS was taken as negative control. All test samples and control samples were incubated at 36 ℃. + -. 1 ℃ for 48h to observe the results. The experiment was repeated 3 times, and the inhibition rate was calculated, and the experimental results are shown in fig. 1.

As can be seen from FIG. 1, compared with the blank group, the polypeptide-modified sodium alginate/PVA hydrogel dressing prepared by the invention has antibacterial activity, and the average antibacterial rate is 79.9%.

While specific embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made within the scope of the technical gist of the present invention in the technical field of the present invention, as long as the general knowledge is grasped.

Claims

1. The polypeptide modified sodium alginate/PVA hydrogel dressing is characterized by comprising the following components in parts by weight: 1-3 parts of sodium alginate derivative, 6-9 parts of polyvinyl alcohol, 5-10 parts of glycerol, 0.1-5 parts of calcium chloride and 73-88 parts of purified water.

2. The polypeptide-modified sodium alginate/PVA hydrogel dressing as claimed in claim 1, wherein the polypeptide-modified sodium alginate/PVA hydrogel dressing is prepared by mixing a sodium alginate polypeptide derivative with polyvinyl alcohol, and combining a repeated freeze-thaw method and an ion crosslinking method.

3. The polypeptide-modified sodium alginate/PVA hydrogel dressing as claimed in claim 2, wherein the sodium alginate polypeptide derivative is obtained by grafting sodium alginate with epsilon-polylysine.

4. The polypeptide-modified sodium alginate/PVA hydrogel dressing as claimed in claim 3, wherein the preparation method of the sodium alginate polypeptide derivative comprises the following steps:

s1: dissolving sodium alginate in 2- (N-morpholino) ethanesulfonic acid buffer solution, adding 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride and N-hydroxysuccinimide, and stirring at normal temperature for 18 hours;

5. The preparation method of the polypeptide-modified sodium alginate/PVA hydrogel dressing as claimed in any one of claims 1 to 4, characterized by comprising the following steps:

s1: dispersing a certain amount of sodium alginate polypeptide derivative in glycerol, adding deionized water, and stirring for dissolving uniformly;

s2, preparing a polyvinyl alcohol aqueous solution, dissolving in a water bath at 85 ℃, blending with S1, pouring into a mold, and repeatedly freezing and thawing for three times to obtain gel;