Iodine-loaded antibacterial starch nanofiber membrane and method of making the same

Abstract

The application discloses a kind of iodine-loaded antibacterial starch nanofiber membrane and preparation method thereof.The method is mixed and handled after starch, strong alkali and ethanol aqueous solution, and then the precipitate is dissolved in water to prepare starch solution, and the starch electrospinning solution is obtained after high-temperature steam cooking, then electrospinning is prepared starch nanofiber membrane, finally solid-phase adsorption iodine vapor to obtain starch-iodine nanofiber membrane.The average fiber diameter of the starch-iodine nanofiber membrane obtained by the application is 127-141 nm, the iodine content is 11.43%-17.00%, and the antibacterial efficiency of staphylococcus aureus and salmonella is highly sensitive, with high antibacterial efficiency, which can be applied to antibacterial wound dressings, tissue scaffolds and food packaging and other fields.

Description

Technical Field

[0001] This invention relates to an iodine-loaded antibacterial starch nanofiber membrane and its preparation method, belonging to the field of antibacterial materials. Background Technology

[0002] Iodine is a highly effective antibacterial agent with broad-spectrum antibacterial activity and low drug resistance, and has been widely used in medical disinfection, wound dressings, tissue scaffolds, and food packaging. However, elemental iodine has low stability, so it needs to be loaded onto appropriate carriers to improve its stability and thus exert its antibacterial activity.

[0003] Chinese patent CN101073325B discloses a method for preparing a novel povidone-iodine antibacterial dressing immobilized with carboxymethyl chitosan, mainly employing a "solution method" to complex iodine molecules with carboxymethyl chitosan grafted with (polyacrylate-copolymer-N-vinylpyrrolidone). Chinese patent CN109771441B discloses a method for preparing a polyethyleneimine-based iodine-loaded antibacterial cellulose material, mainly involving immersing the polyethyleneimine-grafted cellulose material in an iodide aqueous solution to achieve a complexation effect. However, both of these processes involve "solution" preparation, requiring subsequent separation and drying, making the overall process quite cumbersome; furthermore, the non-biobased matrix may lead to potential problems regarding biocompatibility and biodegradability.

[0004] Chinese patent CN112323256B discloses a method for preparing high-iodine polyethersulfone electrospun films by irradiation, mainly through a Coγ radiation graft polymerization reaction. However, this reaction system is carried out in a homogeneous solution, and the selection of polyethersulfone and organic solvents still presents the aforementioned potential biosafety issues. Therefore, there is a need to develop a simple process and highly efficient iodine-loaded bio-based antibacterial material. Summary of the Invention

[0005] The present invention aims to provide a simple, environmentally friendly, and highly effective antibacterial iodine-loaded antibacterial starch nanofiber membrane and its preparation method. The method first prepares amorphous starch with a suitable molecular weight through strong alkali gelatinization and chemical degradation combined with ethanol precipitation. Then, a starch electrospinning solution is prepared by high-temperature steam. After electrospinning, a starch nanofiber membrane is obtained. Finally, the starch nanofiber membrane and iodine vapor are subjected to "solid-phase adsorption" in a closed fumigation device to obtain the iodine-loaded starch nanofiber membrane.

[0006] The technical solution for achieving the objective of this invention is as follows:

[0007] A method for preparing an iodine-loaded antibacterial starch nanofiber membrane includes the following steps:

[0008] (1) Preparation of starch electrospinning solution: The starch, strong alkali, and ethanol aqueous solution were mixed in a ratio of 50-60g: 2-3g: 90-120mL. The mixture was mechanically stirred for 30-60min and allowed to stand for 1-2h to obtain a precipitate. The precipitate was dissolved in water to prepare a starch solution with a mass fraction of 20-25%. The solution was then steamed at high temperature for 15-30min and cooled to room temperature to obtain starch with an average molecular weight of 3-5×10⁻⁶. 6 g / mol starch electrospinning solution;

[0009] (2) Preparation of starch nanofiber membrane by electrospinning: The starch electrospinning solution is loaded into a 5-10 mL syringe, connected to an 18-22 G spinning needle, and the electrospinning voltage is set to 15-20 kV, the spinning distance is 10-14 cm, the syringe flow rate is 0.5-0.8 mL / h, and the roller speed is 30-60 rpm. The starch nanofiber membrane is obtained by electrospinning.

[0010] (3) Preparation of iodine-loaded starch nanofiber membrane: Iodine was placed at the bottom of the fumigation device, and then the starch nanofiber membrane was placed on the four corner magnet plane frame of the polyester wire mesh in the middle layer of the fumigation device. Then, a polypropylene hollow four corner magnet plane frame was covered on top, so that the four corner magnets attracted each other, thereby fixing the nanofiber membrane. The fixed nanofiber membrane was placed on the four-legged support with the membrane surface facing down. After covering with a sealing cover, the environment was controlled at 25-30℃. After fumigation for 1-2 hours, starch-iodine nanofiber membrane was obtained.

[0011] Preferably, in step (1), the amylose content in the starch is 50-70%.

[0012] Preferably, in step (1), the strong base is sodium hydroxide or potassium hydroxide.

[0013] Preferably, in step (1), the volume fraction of ethanol in the aqueous ethanol solution is 40%-60%.

[0014] Preferably, in step (3), the mesh aperture of the mesh planar frame is 0.074-0.147 mm.

[0015] Preferably, in step (3), the fumigation device includes a fumigation device shell, a sealing cover on the top of the fumigation device shell, a solid plastic base plate fixed on the bottom inside the fumigation device shell, the solid plastic base plate being used to place the iodine for fumigation, a four-legged bracket on the top of the solid plastic base plate, a polyester wire mesh four-corner magnet plane frame on the four-corner bracket, a polypropylene hollow four-corner magnet plane frame on the polyester wire mesh four-corner magnet plane frame, and magnets fixed at the four corners of both the polyester wire mesh four-corner magnet plane frame and the polypropylene hollow four-corner magnet plane frame.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] (1) The present invention uses starch as raw material, which is relatively abundant and is a typical bio-based polymer. It is biodegradable and biocompatible. The starch-iodine nanofiber membrane prepared can be applied to fields such as biomedicine, tissue scaffolds or food packaging.

[0018] (2) This invention uses strong alkali gelatinization and chemical degradation combined with ethanol precipitation to prepare amorphous starch with appropriate molecular weight and uses it for electrospinning to prepare starch nanofibers. It does not require the use of chemically controlled organic solvents (such as dimethyl sulfoxide and formic acid), and has the characteristics of being environmentally friendly.

[0019] (3) The present invention performs "solid-phase adsorption" of starch nanofibers and iodine in a closed fumigation device to obtain iodine-loaded starch nanofiber membranes, avoiding the separation and drying processes after the "solution method", and has the characteristics of simple process.

[0020] (4) The starch-iodine nanofiber membrane prepared by the present invention has an average fiber diameter of 127-141 nm and an iodine content of 11.43%-17.00%. It is highly sensitive to the antibacterial efficiency of Staphylococcus aureus and Salmonella. Moreover, it has a better antibacterial effect and is more practical than an equal amount of fiber membrane and a mixture of elemental iodine. It has great application potential in the field of antibacterial wound dressings. Attached Figure Description

[0021] Figure 1 This is a scanning electron microscope image of the starch nanofiber membrane prepared in Comparative Example 3.

[0022] Figure 2 The image shows the fiber diameter distribution and average fiber diameter of the starch nanofiber membrane prepared in Comparative Example 3.

[0023] Figure 3 The elemental distribution diagram is shown for the starch nanofiber membrane prepared in Comparative Example 3.

[0024] Figure 4 The elemental distribution diagram is shown for the starch-iodine nanofiber membrane prepared in Comparative Example 4.

[0025] Figure 5 This is a scanning electron microscope image of the starch-iodine nanofiber membrane prepared in Example 1.

[0026] Figure 6 The image shows the fiber diameter distribution and average fiber diameter of the starch-iodine nanofiber membrane prepared in Example 1.

[0027] Figure 7 The elemental distribution diagram is shown for the starch-iodine nanofiber membrane prepared in Example 1.

[0028] Figure 8 This is a diagram showing the iodine distribution of the starch-iodine nanofiber membrane prepared in Example 1.

[0029] Figure 9 This is a scanning electron microscope image of the starch-iodine nanofiber membrane prepared in Example 2.

[0030] Figure 10 The image shows the fiber diameter distribution and average fiber diameter of the starch-iodine nanofiber membrane prepared in Example 2.

[0031] Figure 11 The elemental distribution diagram is shown for the starch-iodine nanofiber membrane prepared in Example 2.

[0032] Figure 12 This is a scanning electron microscope image of the starch-iodine nanofiber membrane prepared in Example 3.

[0033] Figure 13 The image shows the fiber diameter distribution and average fiber diameter of the starch-iodine nanofiber membrane prepared in Example 3.

[0034] Figure 14 This is an elemental distribution diagram of the starch-iodine nanofiber membrane prepared in Example 3. Detailed Implementation

[0035] The present invention will be further described below with reference to the embodiments and accompanying drawings.

[0036] The fumigation device used in the following embodiments is described in Chinese Patent 202320773924X; the test method used is as follows:

[0037] (1) Scanning electron microscopy observation of the sample

[0038] The sample was fixed on a metal stage with conductive adhesive, vacuum sputtered with gold for 60 seconds, and then the morphology of the sample was observed and photographed at 5000x magnification using a scanning electron microscope (S-4800Ⅱ, Hitachi, Japan). The elemental composition was analyzed by energy dispersive spectroscopy to obtain the relative content of the corresponding elements.

[0039] (2) Evaluation of the antibacterial efficiency of the samples

[0040] Staphylococcus aureus and Salmonella were used as test species for Gram-positive and Gram-negative bacteria, respectively. 250 μL of bacterial suspension was added to 25 mL (50–60 °C) of Brain Heart Infusion (BHI) broth. The mixture was shaken thoroughly and poured onto the top layer of a 1.8% agar plate. After solidification, a fibrous membrane sample cut into 8 mm diameter discs or an equal volume of fibrous membrane and elemental iodine was placed on the plate, with an equal volume of sterile water as a blank control. Diffusion was carried out at 4 °C for 6 hours, followed by continuous incubation at 37 °C for 18 hours. The diameter of the inhibition zone was observed, measured, and recorded using calipers.

[0041] Criteria for judging the antibacterial efficacy of the inhibition zone test: an inhibition zone diameter greater than 20 mm indicates extremely high sensitivity; an inhibition zone diameter between 15-20 mm indicates high sensitivity; an inhibition zone diameter between 10-15 mm indicates moderate sensitivity; an inhibition zone diameter less than 10 mm indicates low sensitivity; and an inhibition zone diameter equal to 8 mm indicates no antibacterial effect.

[0042] Comparative Example 1

[0043] (1) Preparation of starch electrospinning solution: Starch (60% amylose content), sodium hydroxide, and ethanol aqueous solution (40% ethanol by volume) were mixed in a ratio of 50g:3.5g:100mL. The mixture was mechanically stirred for 30min and allowed to stand for 2h to obtain a precipitate. The precipitate was dissolved in water to prepare a 20% starch solution. The solution was then steamed at high temperature for 30min and cooled to room temperature to obtain the starch electrospinning solution with an average molecular weight of 2×10⁻⁶. 6 g / mol;

[0044] (2) Preparation of starch nanofiber membrane by electrospinning: The starch electrospinning solution obtained in step (1) is loaded into a 10mL syringe and connected to a 20G spinning needle. The electrospinning voltage is 15kV, the spinning distance is 12cm, the syringe flow rate is 0.5mL / h, the roller speed is 30rpm, and then electrospinning is performed.

[0045] Tests revealed that excessive sodium hydroxide content resulted in an excessively low molecular weight of starch in the starch electrospinning solution, with an average molecular weight of 2 × 10⁻⁶. 6 The starch electrospinning solution of g / mol could not produce fiber membrane samples, which is related to the electrostatic spraying phenomenon caused by insufficient intermolecular entanglement due to its low average molecular weight.

[0046] Comparative Example 2

[0047] (1) Preparation of starch electrospinning solution: Starch (60% amylose content), sodium hydroxide, and ethanol aqueous solution (40% ethanol by volume) were mixed in a ratio of 50g:1.5g:100mL. The mixture was mechanically stirred for 30min, and allowed to stand for 2h to obtain a precipitate. The precipitate was dissolved in water to prepare a 20% starch solution. The solution was then steamed at high temperature for 30min and cooled to room temperature to obtain the starch electrospinning solution with an average molecular weight of 6×10⁻⁶. 6 g / mol;

[0048] (2) Preparation of starch nanofiber membrane by electrospinning: The starch electrospinning solution obtained in step (1) is loaded into a 10mL syringe and connected to a 20G spinning needle. The electrospinning voltage is 15kV, the spinning distance is 12cm, the syringe flow rate is 0.5mL / h, the roller speed is 30rpm, and then electrospinning is performed.

[0049] Tests revealed that the excessively low amount of sodium hydroxide resulted in an excessively high molecular weight of starch in the starch electrospinning solution, with an average molecular weight of 6 × 10⁻⁶. 6 The starch electrospinning solution of g / mol could not produce fiber membrane samples because its high average molecular weight resulted in excessive solution viscosity, which hindered electrospinning.

[0050] Comparative Example 3

[0051] (1) Preparation of starch electrospinning solution: Starch (60% amylose content), sodium hydroxide, and ethanol aqueous solution (40% ethanol by volume) were mixed in a ratio of 50g:2.5g:100mL. The mixture was mechanically stirred for 30min and allowed to stand for 2h to obtain a precipitate. The precipitate was dissolved in water to prepare a 20% starch solution. The solution was then steamed at high temperature for 30min and cooled to room temperature to obtain the starch electrospinning solution with an average molecular weight of 4×10⁻⁶. 6 g / mol;

[0052] (2) Electrospinning to prepare starch nanofiber membrane: The starch electrospinning solution obtained in step (1) is loaded into a 10mL syringe and connected to a 20G spinning needle; the electrospinning voltage is 15kV, the spinning distance is 12cm, the syringe flow rate is 0.5mL / h, the roller speed is 30rpm, and then electrospinning is performed to obtain starch nanofiber membrane.

[0053] The average molecular weight was measured to be 4 × 10⁻⁶. 6 A starch nanofiber membrane can be obtained from an electrospinning solution of g / mol, and its microstructure exhibits a network structure formed by interwoven nanofibers. Figure 1Its average fiber diameter is 127 nm. Figure 2 Energy dispersive spectroscopy (EDS) results showed that its iodine content was 0%. Figure 3 It showed no antibacterial effect against Staphylococcus aureus and Escherichia coli (the diameter of the inhibition zone was 8 mm).

[0054] Comparative Example 4

[0055] (1) and (2) were prepared in the same manner as in Comparative Example 3 to obtain starch nanofiber membranes.

[0056] (3) Preparation of iodine-loaded starch nanofiber membrane: Place 2g of elemental iodine at the bottom of the fumigation device, and then place the starch nanofiber membrane obtained in step (2) cut into circular pieces (diameter 8mm) on the polyester wire mesh four-corner magnetic plane frame (mesh aperture is 0.1mm) in the middle layer of the fumigation device, and then cover it with a polypropylene hollow four-corner magnetic plane frame so that the four corner magnets attract each other, thereby fixing the nanofiber membrane. Place the fixed nanofiber membrane on the four-legged support with the membrane surface facing down, cover it with a sealing cap, control the environment at 25℃, and fumigate for 0.5h to obtain the iodine-loaded starch nanofiber membrane, which is the starch-iodine nanofiber membrane.

[0057] The energy dispersive spectroscopy (EDS) results of the obtained starch-iodine nanofiber membrane showed that its iodine content was 7.32%. Figure 4 The inhibitory efficiency against Staphylococcus aureus and Escherichia coli was moderately sensitive (inhibition zone diameters were 11.8 mm and 10.5 mm, respectively), which was related to insufficient iodine loading due to insufficient fumigation time.

[0058] Comparative Example 5

[0059] (1) and (2) were prepared in the same manner as in Comparative Example 3 to obtain starch nanofiber membranes.

[0060] (3) Preparation of iodine-loaded starch nanofiber membrane: Place 2g of elemental iodine at the bottom of the fumigation device, and then place the starch nanofiber membrane obtained in step (2) cut into circular pieces (diameter 8mm) on the polyester wire mesh four-corner magnetic plane frame (mesh aperture is 0.1mm) in the middle layer of the fumigation device, and then cover it with a polypropylene hollow four-corner magnetic plane frame so that the four corner magnets attract each other, thereby fixing the nanofiber membrane. Place the fixed nanofiber membrane on the four-legged support with the membrane surface facing down, cover it with a sealing cap, control the environment at 25℃, and fumigate for 2.5h to obtain the iodine-loaded starch nanofiber membrane, which is the starch-iodine nanofiber membrane.

[0061] Tests revealed a brownish-purple liquid on the obtained starch-iodine nanofiber membrane, which was related to the liquefaction of iodine vapor caused by excessive fumigation time. This severely affected the appearance of the fiber membrane and made it unsuitable for further application.

[0062] Comparative Example 6

[0063] (1) and (2) are the same starch nanofiber membranes prepared in Example 1.

[0064] (3) Preparation of equal amounts of starch nanofiber membrane and elemental iodine mixture: The starch nanofiber membrane obtained in step (2) is physically mixed with an equal amount of elemental iodine (iodine content is 17.00%) in Example 1 to obtain an equal amount of starch nanofiber membrane and elemental iodine mixture.

[0065] Tests showed that the obtained starch nanofiber membrane and elemental iodine mixture (iodine content of 17.00%) exhibited low sensitivity to both Staphylococcus aureus and Escherichia coli (inhibition zone diameters were 9.2 mm and 8.5 mm, respectively).

[0066] Example 1

[0067] (1) Preparation of starch electrospinning solution: Starch (70% amylose), sodium hydroxide, and ethanol aqueous solution (40% ethanol by volume) were mixed in a ratio of 55g:2.5g:100mL. The mixture was mechanically stirred for 60min and allowed to stand for 2h to obtain a precipitate. The precipitate was dissolved in water to prepare a 25% starch solution. The solution was then steamed at high temperature for 30min and cooled to room temperature to obtain the starch electrospinning solution with an average molecular weight of 5×10⁻⁶. 6 g / mol;

[0068] (2) Preparation of starch nanofiber membrane by electrospinning: The starch electrospinning solution obtained in step (1) is loaded into a 10mL syringe and connected to a 22G spinning needle; the electrospinning voltage is 20kV, the spinning distance is 10cm, the syringe flow rate is 0.8mL / h, and the roller speed is 60rpm. After electrospinning, starch nanofiber membrane is obtained.

[0069] (3) Preparation of iodine-loaded starch nanofiber membrane: Place 3g of elemental iodine at the bottom of the fumigation device, and then place the starch nanofiber membrane obtained in step (2) cut into circular pieces (diameter 8mm) on the polyester wire mesh four-corner magnetic plane frame (mesh aperture of 0.147mm) in the middle layer of the fumigation device, and then cover it with a polypropylene hollow four-corner magnetic plane frame so that the four corner magnets attract each other, thereby fixing the nanofiber membrane. Place the fixed nanofiber membrane on the four-legged support with the membrane surface facing down, cover it with a sealing cap, control the environment at 30℃, and fumigate for 2 hours to obtain the iodine-loaded starch nanofiber membrane, which is the starch-iodine nanofiber membrane.

[0070] Testing revealed that the obtained starch-iodine nanofiber membrane exhibited a network structure formed by interwoven nanofibers. Figure 5Its average fiber diameter is 141 nm. Figure 6 The energy dispersive spectroscopy (EDS) results showed that its iodine content was 17.00%. Figure 7 The distribution of its iodine element is as follows: Figure 8 As shown, iodine is evenly distributed on the surface of the fiber membrane; it exhibits high sensitivity to both Staphylococcus aureus and Escherichia coli (the diameters of the inhibition zones are 19.7 mm and 18.3 mm, respectively).

[0071] Example 2

[0072] (1) Preparation of starch electrospinning solution: Starch (50% amylose), potassium hydroxide, and ethanol aqueous solution (60% ethanol by volume) were mixed in a ratio of 50g:2g:90mL. The mixture was mechanically stirred for 30min and allowed to stand for 1h to obtain a precipitate. The precipitate was dissolved in water to prepare a 20% starch solution. The solution was then steamed at high temperature for 20min and cooled to room temperature to obtain the starch electrospinning solution with an average molecular weight of 3×10⁻⁶. 6 g / mol;

[0073] (2) Preparation of starch nanofiber membrane by electrospinning: The starch electrospinning solution obtained in step (1) is loaded into a 5mL syringe and connected to an 18G spinning needle; the electrospinning voltage is 15kV, the spinning distance is 14cm, the syringe flow rate is 0.6mL / h, and the roller speed is 40rpm. After electrospinning, starch nanofiber membrane is obtained.

[0074] (3) Preparation of iodine-loaded starch nanofiber membrane: Place 1g of elemental iodine at the bottom of the fumigation device, and then place the starch nanofiber membrane obtained in step (2) cut into round pieces (diameter 8mm) on the polyester wire mesh four-corner magnetic plane frame (mesh aperture is 0.074mm) in the middle layer of the fumigation device, and then cover it with a polypropylene hollow four-corner magnetic plane frame so that the four corner magnets attract each other, thereby fixing the nanofiber membrane. Place the fixed nanofiber membrane on the four-legged support with the membrane surface facing down, cover it with a sealing cap, control the environment at 25℃, and fumigate for 1h to obtain the iodine-loaded starch nanofiber membrane, which is the starch-iodine nanofiber membrane.

[0075] Testing revealed that the obtained starch-iodine nanofiber membrane exhibited a network structure formed by interwoven nanofibers. Figure 9 Its average fiber diameter is 127 nm. Figure 10 Energy dispersive spectroscopy (EDS) results showed that its iodine content was 11.43%. Figure 11 It showed high sensitivity to both Staphylococcus aureus and Escherichia coli (inhibition zone diameters were 16.2 mm and 15.0 mm, respectively).

[0076] Example 3

[0077] (1) Preparation of starch electrospinning solution: Starch (60% amylose), sodium hydroxide, and ethanol aqueous solution (50% ethanol by volume) were mixed in a ratio of 60g:3g:120mL. The mixture was mechanically stirred for 45min and allowed to stand for 1.5h to obtain a precipitate. The precipitate was dissolved in water to prepare a 22% starch solution. The solution was then steamed at high temperature for 15min and cooled to room temperature to obtain the starch electrospinning solution with an average molecular weight of 4.5×10⁻⁶. 6 g / mol;

[0078] (2) Preparation of starch nanofiber membrane by electrospinning: The starch electrospinning solution obtained in step (1) is loaded into an 8mL syringe and connected to a 20G spinning needle. The electrospinning voltage is 18kV, the spinning distance is 12cm, the syringe flow rate is 0.5mL / h, and the roller speed is 50rpm. After electrospinning, starch nanofiber membrane is obtained.

[0079] (3) Preparation of iodine-loaded starch nanofiber membrane: Place 2g of elemental iodine at the bottom of the fumigation device, and then place the starch nanofiber membrane obtained in step (2) cut into circular pieces (diameter 8mm) on the polyester wire mesh four-corner magnetic plane frame (mesh aperture is 0.12mm) in the middle layer of the fumigation device, and then cover it with a polypropylene hollow four-corner magnetic plane frame so that the four corner magnets attract each other, thereby fixing the nanofiber membrane. Place the fixed nanofiber membrane on the four-legged support with the membrane surface facing down, cover it with a sealing cover, control the environment at 28℃, and fumigate for 1.5h to obtain the iodine-loaded starch nanofiber membrane, which is the starch-iodine nanofiber membrane.

[0080] Testing revealed that the obtained starch-iodine nanofiber membrane exhibited a network structure formed by interwoven nanofibers. Figure 12 Its average fiber diameter is 138 nm. Figure 13 Energy dispersive spectroscopy (EDS) results showed that its iodine content was 14.92%. Figure 14 It showed high sensitivity to both Staphylococcus aureus and Escherichia coli (inhibition zone diameters were 17.8 mm and 16.3 mm, respectively).

Claims

1. A method for preparing iodine-loaded antibacterial starch nanofiber membranes, characterized by, The method comprises the following steps: (1) Preparation of starch electrospinning solution: according to the ratio of starch, strong base, ethanol aqueous solution is 50-60 g: 2-3 g: 90-120 mL, the starch, strong base, ethanol aqueous solution is mixed, mechanical stirring 30-60 min, stand for 1-2 h to get the precipitate, the precipitate is dissolved in water to prepare a starch solution with a mass fraction of 20-25%, and then the solution is heated by high-temperature steam for 15-30 min and cooled to room temperature to obtain a starch electrospinning solution with an average molecular weight of 3-5 × 10 6 g / mol, the amylose content in the starch is 50-70%, and the volume fraction of ethanol in the ethanol aqueous solution is 40%-60%; (2) electrospinning preparation of starch nanofiber membrane: the starch electrospinning solution is loaded into a 5-10 mL needle tube syringe, an 18-22 G spinning needle is connected, the electrospinning voltage is set to 15-20 kV, the spinning distance is 10-14 cm, the syringe flow rate is 0.5-0.8 mL / h, and the drum rotation speed is 30-60 rpm, and the electrospinning starch nanofiber membrane is obtained; (3) preparation of iodine-loaded starch nanofiber membrane: iodine is placed at the bottom of the fumigation device, then the starch nanofiber membrane is placed on the polyester wire mesh four-magnet plane frame in the middle layer of the fumigation device, and a hollow four-magnet plane frame is covered, so that the four magnets attract each other to fix the nanofiber membrane, the fixed nanofiber membrane is placed on a four-legged support with the membrane facing down, a sealing cover is covered, the environment is controlled at 25-30 ℃, and after fumigation for 1-2 h, the starch-iodine nanofiber membrane is obtained.

2. The production method according to claim 1, characterized by, In step (1), the strong base is sodium hydroxide or potassium hydroxide.

3. The production method according to claim 1, characterized by, In step (3), the grid aperture of the grid plane frame is 0.074-0.147 mm.

4. The method of claim 1, wherein, In step (3), the fumigation device comprises a fumigation device shell, a sealing cover is arranged above the fumigation device shell, a plastic solid bottom disc is fixed on the inner side of the fumigation device shell, the plastic solid bottom disc is used for placing the fumigated iodine, a four-legged support is arranged above the plastic solid bottom disc, a polyester wire mesh four-magnet plane frame is arranged on the four-legged support, a hollow four-magnet plane frame is arranged on the polyester wire mesh four-magnet plane frame, and magnets are fixed on the four corners of the polyester wire mesh four-magnet plane frame and the hollow four-magnet plane frame.

5. The iodine-loaded antibacterial starch nanofiber membrane prepared by the preparation method of any one of claims 1-4.

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