PEDOT conductive gel based on bacterial cellulose PSS template, preparation method and application of PEDOT conductive gel in biosensor

Abstract

The invention discloses PEDOT conductive gel based on a bacterial cellulose PSS template, a preparation method of the PEDOT conductive gel and application of the PEDOT conductive gel in a biosensor, and belongs to the technical field of conductive gel. The method comprises the following steps: carrying out mechanical crushing treatment on bacterial cellulose to obtain treated bacterial cellulose; sodium p-styrenesulfonate is combined with the treated bacterial cellulose in a physical blending mode and a chemical grafting mode, and a BC / PSS template and an ACBC-g-PSS template are formed; and carrying out oxyradical polymerization and deposition on the EDOT in the formed BC / PSS template and BC-g-PSS template by using ammonium persulfate to obtain the PEDOT conductive gel based on the bacterial cellulose PSS template. The preparation method has the beneficial effects that the bacterial cellulose is used as a template, so that the conductivity of the conductive hydrogel is improved, the safety and compatibility of the conductive hydrogel in a living body are ensured, and a foundation is laid for the application of the conductive hydrogel in the field of biomedicine.

Description

Technical Field

[0001] The present invention relates to the technical field of conductive gels, and particularly relates to a PEDOT conductive gel based on a bacterial cellulose PSS template, a preparation method thereof, and an application thereof in a biosensor. Background Art

[0002] Due to its unique physical and chemical properties, conductive hydrogels have shown broad application prospects in the fields of flexible electronics, biomedicine, energy storage and conversion, etc. As a common conductive polymer, PEDOT:PSS is widely used in the preparation of conductive hydrogels. However, the conductivity of PEDOT:PSS conductive hydrogels is generally low, which limits its application in high-performance electronic devices. The problem of low conductivity of PEDOT:PSS conductive hydrogels has not been effectively solved. This is mainly because it is difficult to construct an effective conductive network of PEDOT, and the post-treatment enhancement process is cumbersome and complex. In the preparation process of PEDOT:PSS hydrogels, how to achieve the effective dispersion of PEDOT and construct an ordered conductive network has become a key technical problem for improving conductivity. Although researchers have conducted a large number of explorations on this, the effects are still not satisfactory.

[0003] In recent years, studies have shown that bacterial cellulose, as a natural polymer material, has good biocompatibility, a high specific surface area, and excellent mechanical properties. When it is compounded with PEDOT:PSS, it can effectively load and disperse PEDOT:PSS, thereby improving the conductive performance of the conductive hydrogel. However, how to construct a long-range ordered and uniformly dispersed conductive network through template action in the hydrogel system to further improve the electrical sensing performance of the conductive hydrogel is still a major challenge in current research.

[0004] In addition, the mechanism generated by the template effect has not been clearly studied yet. The template effect plays a key role in the preparation process of conductive hydrogels. It affects the dispersion, deposition, and arrangement of PEDOT:PSS, and thus affects the overall performance of the conductive hydrogel. Revealing the mechanism of the template effect helps us better regulate the microstructure of the conductive hydrogel and optimize its performance.

[0005] In summary, the current research on PEDOT:PSS conductive hydrogels still has the following deficiencies: one is the low conductivity, the second is the complex construction of the effective conductive network of PEDOT and the post-treatment enhancement process, the third is how to construct a long-range ordered and uniformly dispersed conductive network in the hydrogel system, and the fourth is that the mechanism of the template effect is not clear. Aiming at these problems, the present invention aims to propose a new method for preparing conductive hydrogels, in order to provide strong support for the research and application of high-performance conductive hydrogels. Summary of the Invention

[0006] The object of the present invention is to provide a PEDOT conductive gel based on a bacterial cellulose PSS template, a preparation method thereof, and an application thereof in a biosensor, which can solve at least one technical problem involved in the background art.

[0007] To solve the above technical problems, the present invention is implemented as follows: The present invention provides a preparation method of a PEDOT conductive gel based on a bacterial cellulose PSS template, comprising the following steps: Step S1, subjecting the bacterial cellulose purified by washing with an NaOH solution to mechanical fragmentation treatment to obtain treated bacterial cellulose; Step S2, combining sodium styrene sulfonate with the treated bacterial cellulose in a physical blending and chemical grafting manner respectively to form a BC / PSS template and an ACBC-g-PSS template; Step S3, subjecting EDOT to oxidative radical polymerization and deposition with ammonium persulfate in the formed BC / PSS template and ACBC-g-PSS template to obtain a PEDOT conductive gel based on a bacterial cellulose PSS template.

[0008] Optionally, step S1 specifically includes: Step S11, placing Acetobacter xylinum in a culture medium added with black tea soup and glucose, and statically culturing for 7 - 15 days to obtain a bacterial cellulose membrane; Step S12, washing the obtained bacterial cellulose membrane with a 1wt.% NaOH solution in a water bath at 80 - 90 °C for more than 5 h until the bacterial cellulose membrane changes from black tea color to white; Step S13, then pouring the whitened bacterial cellulose membrane into 99wt.% deionized water at a ratio of 1:99 for mechanical fragmentation to obtain bacterial cellulose.

[0009] Optionally, in step S2, combining sodium styrene sulfonate with the treated bacterial cellulose in a chemical grafting manner to form a BC-g-PSS template specifically includes: Treating the treated bacterial cellulose with acryloyl chloride, and after the reaction is complete, using triethylamine as a catalyst in an N,N-dimethylformamide solvent to react acryloyl chloride with the hydroxyl groups on the bacterial cellulose, thereby introducing the acrylate group of acryloyl chloride onto the bacterial cellulose to obtain chlorinated bacterial cellulose; Performing an ammonium persulfate oxidative polymerization reaction on sodium styrene sulfonate and chlorinated bacterial cellulose in an N,N-dimethylformamide-deionized water mixed solution to obtain ACBC-g-PSS.

[0010] Optionally, the molar ratio of bacterial cellulose to acryloyl chloride is 10:1; the molar ratio of triethylamine to bacterial cellulose is 15:1; the molar ratio of sodium styrene sulfonate to chlorinated bacterial cellulose is 1:1.

[0011] Optionally, in the N,N-dimethylformamide-deionized water mixed solution, the volume ratio of N,N-dimethylformamide to deionized water is 1:1.

[0012] Optionally, the dosage of ammonium persulfate is 1 wt.% of sodium styrene sulfonate.

[0013] Optionally, step S3 specifically includes: Adding EDOT, ferric chloride, and ammonium persulfate into the BC / PSS template and the ACBC-g-PSS template to obtain the ACBC-g-PSS / PEDOT solution. After removing part of the water, a BC-g-PSS / PEDOT gel is obtained. The BC-g-PSS / PEDOT gel is frozen at -60 °C and then dried to obtain a PEDOT conductive gel based on the bacterial cellulose PSS template.

[0014] Optionally, the content of ferric chloride is 1 / 20 of the mass of EDOT; the mass ratio of ammonium persulfate to EDOT is 1:30.

[0015] The present invention also provides a PEDOT conductive gel based on the bacterial cellulose PSS template, which is prepared by using the described preparation method.

[0016] The present invention also applies the PEDOT conductive gel based on the bacterial cellulose PSS template to a resistive biosensor.

[0017] The beneficial effects of the present invention are as follows: (1) In terms of material selection, the present invention innovatively uses bacterial cellulose as the main biomass template, which has significant environmental friendliness and biocompatibility. As a renewable natural polymer material, the production process of bacterial cellulose has less impact on the environment, which is conducive to the sustainable utilization of resources. At the same time, the biocompatibility of bacterial cellulose makes it have broad application potential in the biomedical field. By using bacterial cellulose as the template, the present invention not only improves the conductivity of the conductive hydrogel but also ensures the safety and compatibility of the material in the body, laying a foundation for the application of the conductive hydrogel in the biomedical field.

[0018] (2) The BC / PSS template used in the present invention enables a simple preparation process with remarkable effects through physical electrostatic adsorption. As a mild preparation method, physical electrostatic adsorption avoids complex chemical reaction steps, reduces production costs, and improves production efficiency. In addition, due to the specificity of the electrostatic adsorption effect, the BC / PSS template can effectively guide the deposition of PEDOT:PSS, thereby forming a uniform conductive network. This method not only improves the conductivity of the conductive hydrogel but also maintains the stability of the material structure, facilitating the practical application of the conductive hydrogel.

[0019] (3) In the present invention, BC-g-PSS forms a template through a stronger chemical bond binding method. This binding method makes the deposition and secondary arrangement of PEDOT on the template more orderly. This orderly long-range arrangement and assembly not only greatly improve the conductive performance of the conductive hydrogel but also significantly enhance its mechanical properties. The chemical bond binding method of the BC-g-PSS template ensures the uniform distribution and stable existence of PEDOT:PSS in the hydrogel, enabling the conductive hydrogel to maintain excellent performance under multiple uses and mechanical stress. This innovation provides strong support for the application of conductive hydrogels in flexible electronic devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings, where: Figure 1 (a)~ Figure 1 (c) are scanning electron microscope images of the deposition of bacterial cellulose (BC) and BC / PSS template on PEDOT provided by the present invention; Figure 2 (a)~and Figure 2 (b) are internal conductive fiber diagrams of the PEDOT conductive hydrogel prepared with and without the BC / PSS template provided by the present invention; Figure 3 (a)~ Figure 3 (f) are diagrams of the biosensing application of the PEDOT conductive hydrogel prepared with the BC / PSS template provided by the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0021] The technical solutions in the present invention will be clearly and completely described below in conjunction with the present invention. Obviously, the described embodiments are some of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0022] The present invention provides a method for preparing a PEDOT conductive gel based on a bacterial cellulose PSS template, comprising the following steps: Step S1, subjecting the bacterial cellulose purified by washing with a NaOH solution to mechanical fragmentation treatment to obtain treated bacterial cellulose; Step S2, combining sodium styrene sulfonate with the treated bacterial cellulose by physical blending and chemical grafting methods respectively to form a BC / PSS template and an ACBC-g-PSS template; Step S3, subjecting EDOT to oxidative radical polymerization and deposition in the formed BC / PSS template and BC-g-PSS template with ammonium persulfate to obtain a PEDOT conductive gel based on a bacterial cellulose PSS template.

[0023] Step S1 specifically includes: Step S11, placing Acetobacter xylinum in a culture medium added with black tea soup and glucose, and statically culturing for 7 - 15 days to obtain a bacterial cellulose membrane; Step S12, washing the obtained bacterial cellulose membrane with a 1wt.% NaOH solution in a water bath at 80 - 90 °C for more than 5 h until the bacterial cellulose membrane changes from black tea color to white; Step S13, then pouring the whitened bacterial cellulose membrane into 99wt.% deionized water at a ratio of 1:99 for mechanical fragmentation to obtain a 1wt.% bacterial cellulose solution.

[0024] In step S2, combining sodium styrene sulfonate with the treated bacterial cellulose by chemical grafting to form a BC-g-PSS template specifically includes: Treating the treated bacterial cellulose with acryloyl chloride. After the reaction is complete, using triethylamine (TEA) as a catalyst in N,N-dimethylformamide (DMF) solvent, reacting acrylate with the hydroxyl groups on the bacterial cellulose, thereby introducing the acrylate group of acryloyl chloride onto the bacterial cellulose to obtain chlorinated bacterial cellulose (ACBC); Performing an ammonium persulfate (APS) oxidative polymerization reaction on sodium styrene sulfonate (1mol / L) and ACBC (1mol / L) in a N,N-dimethylformamide-deionized water mixed solution to obtain ACBC-g-PSS.

[0025] Among them, the molar ratio of bacterial cellulose to acryloyl chloride is 10:1; the molar ratio of triethylamine to bacterial cellulose is 15:1; the molar ratio of sodium styrene sulfonate to chlorinated bacterial cellulose is 1:1.

[0026] Among them, in the N,N-dimethylformamide-deionized water mixed solution, the volume ratio of N,N-dimethylformamide to deionized water is 1:1.

[0027] Among them, the dosage of ammonium persulfate is 1 wt.% of sodium styrene sulfonate.

[0028] Step S3 specifically includes: Adding EDOT, ferric chloride, and ammonium persulfate into the BC / PSS template and the ACBC-g-PSS template to obtain an ACBC-g-PSS / PEDOT solution. After removing part of the water, a BC-g-PSS / PEDOT gel is obtained. The BC-g-PSS / PEDOT gel is frozen at -60 °C and then dried to obtain a PEDOT conductive gel based on the bacterial cellulose PSS template.

[0029] Among them, the content of ferric chloride is 1 / 20 of the mass of EDOT; the mass ratio of ammonium persulfate to EDOT is 1:30.

[0030] Combined Figure 1 (a)~ Figure 1 (c) As shown, it can be seen that the internal structure of bacterial cellulose is smooth, while the fibers deposited with PEDOT after forming the template are rough and granular, indicating that bacterial cellulose can effectively serve as a template for depositing the conductive polymer PEDOT.

[0031] The present invention also provides a PEDOT conductive gel based on the bacterial cellulose PSS template, which is prepared by using the described preparation method.

[0032] From Figure 2 (a) As shown, it can be seen that in the conductive hydrogel without the BC template, the internal conductive particles are obviously dispersed and the conductivity is low; combined with Figure 2 (b) As shown, it can be seen that in the conductive polymer hydrogel with the BC / PSS template, it is evenly dispersed, the conductive phase is deposited on the BC fibers, and after treatment with the DMSO polar solvent, a continuous conductive path is obtained, improving the conductivity.

[0033] The present invention also applies the PEDOT conductive gel based on the bacterial cellulose PSS template to a resistive biosensor, see Figure 3 (a)~ Figure 3As shown in (f), it can be seen that the PEDOT conductive gel prepared by the BC / PSS template provided by the present invention is applied to a resistive biosensor, and the conductive hydrogel has the function of quickly identifying motion signals, proving that the method of improving conductivity by the template method is effective.

[0034] It should be noted that in this article, the term "including", "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of additional identical elements in the process, method, article or device including that element.

[0035] In addition, it should be pointed out that the methods and applications in capacitors in the embodiments of the present invention are not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in the reverse order according to the functions involved. For example, the described methods may be performed in an order different from that described, and various steps may be added, omitted, or combined. Additionally, the features described with reference to certain examples may be combined in other examples.

[0036] The embodiments of the present invention have been described above, but the present invention is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present invention, those of ordinary skill in the art can also make many forms without departing from the spirit and scope protected by the claims of the present invention, and all of them belong to the protection scope of the present invention.

Claims

1. A method for preparing PEDOT conductive gel based on bacterial cellulose PSS template, characterized in that: The steps include: Step S1, mechanically crushing the purified bacterial cellulose after washing with a NaOH solution to obtain treated bacterial cellulose; Step S2, combining sodium styrene sulfonate with the treated bacterial cellulose by physical blending and chemical grafting to form a BC / PSS template and an ACBC-g-PSS template; Step S3, EDOT is subjected to oxidative free radical polymerization in the formed BC / PSS template and ACBC-g-PSS template using ammonium persulfate, and deposited to obtain a PEDOT conductive gel based on the bacterial cellulose PSS template.

2. The preparation method according to claim 1, characterized in that: Step S1 specifically includes: Step S11, placing Acetobacter xylinum in a culture medium, adding black tea soup and glucose, and statically culturing for 7-15 days to obtain a bacterial cellulose film; Step S12, washing the obtained bacterial cellulose membrane with 1 wt.% NaOH solution in a water bath at 80-90 degrees for more than 5 hours until the bacterial cellulose membrane changes from black tea color to white; Step S13, pouring the bacterial cellulose membrane that has turned white into 99 wt.% deionized water at a ratio of 1:99 to mechanically crush it to obtain bacterial cellulose.

3. The preparation method according to claim 2, characterized in that: In step S2, sodium styrene sulfonate is chemically grafted with the treated bacterial cellulose to form a BC-g-PSS template, which specifically includes: The treated bacterial cellulose is treated with acryloyl chloride. After the reaction is complete, triethylamine is used as a catalyst in N,N-dimethylformamide solvent to react acryloyl chloride with hydroxyl groups on the bacterial cellulose, thereby introducing the acrylate group of acryloyl chloride into the bacterial cellulose to obtain chlorinated bacterial cellulose; ACBC-g-PSS was obtained by oxidative polymerization of sodium styrene sulfonate with chlorinated bacterial cellulose in a mixed solution of N,N-dimethylformamide and deionized water through ammonium persulfate.

4. The preparation method according to claim 3, characterized in that: The molar ratio of bacterial cellulose to acryloyl chloride is 10:1; the molar ratio of triethylamine to bacterial cellulose is 15:1; and the molar ratio of sodium styrene sulfonate to chlorinated bacterial cellulose is 1:

1.

5. The preparation method according to claim 4, characterized in that: The volume ratio of N,N-dimethylformamide to deionized water in the N,N-dimethylformamide-deionized water mixed solution is 1:

1.

6. The preparation method according to claim 5, characterized in that: The amount of ammonium persulfate used is 1 wt.% of sodium styrene sulfonate.

7. The preparation method according to claim 3, characterized in that: Step S3 specifically includes: EDOT, ferric chloride and ammonium persulfate were added to the BC / PSS template and ACBC-g-PSS template to obtain ACBC-g-PSS / PEDOT solution. After removing part of the water, BC-g-PSS / PEDOT gel was obtained. The BC-g-PSS / PEDOT gel was frozen at -60°C and then dried to obtain PEDOT conductive gel based on bacterial cellulose PSS template.

8. The preparation method according to claim 7, characterized in that: The ferric chloride content is 1 / 20 of the mass of EDOT; the mass ratio of ammonium persulfate to EDOT is 1:

30.

9. A PEDOT conductive gel based on bacterial cellulose PSS template, characterized in that: The method is prepared by any one of claims 1 to 8.

10. The PEDOT conductive gel based on bacterial cellulose PSS template prepared by the preparation method according to any one of claims 1 to 8 is applied to a resistive biosensor.

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