| Along with the development of regenerative medicine and smart biomaterials,with electricity-force-more than chemical response characteristics of intelligent biological gel state materials in tissue repair,drug delivery and controlled release,the research and application of biological sensors have more and more be taken seriously,study on alternating field force-electric response in vivo hydrogel materials and their regulation and tissue fitment,repair of heart,nerve regeneration and reconstruction functions play an important role.Currently insufficient mechanical strength of the hydrogel,however,in the body of long-term mechanical stability is poorer,and the force of synthesis electrical response hydrogels mostly poor biocompatibility,power electrical response performance of the mechanism and affecting factors are not clear,and the water gel strength-power for cell growth and the effect of related research is largely confined to change under electrostatic field and constant force field,in alternating electric field,especially in vivo biological potential,spontaneous contraction and under the action of pulsating,determined by its microstructure force electric synergy and the influence of dynamic balance process for cell growth and proliferation of conclusive evidence.This article is based on the existing model and mechanism of the hydrogel in electrostatic field response,through the functional modification of bacterial cellulose nanocrystals to improve the structure and performance of the hydrogel,to build with ordering structure anisotropy nanocomposite hydrogels,realize the alternating field response of the driving force electric coupling characteristics,study its physiological-electric field under the action of alternating force influence on cell growth and proliferation,investigate and verify water gel structure and the coupled action of alternating electric field force of cardiac muscle cells,nerve cells growth,skeleton,and morphology.The research results are as follows:1)Firstly,PVA hydrogel was composite modified by using bacterial cellulose nanocrystalline(BCNC)as raw material,and the influences of bacterial cellulose nanocrystalline on the microstructure,hydrogen bond,mechanical properties and fatigue resistance of the composite hydrogel were studied.Moderate BCNC to effectively increase the hydrogen bonds in the PVA hydrogel and junction,hydrogels form uniform and orderly network structure,the tensile strength increased by 160%,a 97%increase over the young's modulus,creep and fatigue resistance performance has been significantly improved,but as the BCNC to join,too much BCNC reunion,uniform network structure was destroyed,performance is greatly reduced.The best PVA:BCNC ratio is 20:1.2)Secondly,the bacterial cellulose nanocrystals were sulfonated to endow the composite hydrogels with electro-mechanical response characteristics,and the effects of different conditions on the electro-mechanical response properties of hydrogels were studied.The experimental results shpwed that the degree of substitution of SBC was 40%,The Times of cross-linking of hydrogels were 3 times,the pore structure of hydrogels was small holes,and the hydrodynamic response performance of hydrogels was the best.The response Angle of hydrogel is positively correlated with the external electric field strength and pH,while the response Angle is the largest when the solution ionic strength is about 0.1mol/L.The response performance of the water gel with alternating electric field is related to the electric field intensity and frequency.The higher the electric field intensity is,the lower the alternating frequency is,and the greater the response strain of the hydrogel is.3)Thirdly,the orientation treatment of hydrogel was conducted by using the gradient field induced orientation method.The oriented SBC-PVA-PPy hydrogel was prepared by coating polypyrrole conductive layer.Orientation sbc-pva-PPy hydrogel has anisotropic conductivity,and the highest conductivity along orientation direction is 3.4×10-3s/cm.The mechanical properties also showed anisotropy,and the tensile strength in the orientation direction was 2.5 times higher than that in the vertical orientation direction.The electro-mechanical response of the oriented sbc-pva-PPy hydrogel also showed anisotropy,and the maximum bending strain perpendicular to the orientation direction was 1.5 times higher than that in the orientation direction.With the increase of PPy concentration,PPy spills over the structure of the hydrogel network and completely covers the surface of the hydrogel,reducing the anisotropy of the hydrogel.4)Finally,the effects of electro-mechanical coupling of hydrogels under alternating electric field on the growth,cytoskeleton and micromorphology of cardiomyocytes(H9C2)and nerve cells(PC 12)were studied.The experimental results show that the water gel force electric coupling force electric coupling can effectively improve the two kinds of cell adhesion and growth,orientation of the hydrogel directional force electric coupling can significantly improve cell growth and value orientation,promote cell spreading along the orientation direction and elongation,and generate the pseudopodia,force response hydrogels in tissue repair applications provides the experimental basis.All in all,success,this paper builds functional modified bacterial cellulose nanocrystals-poly(vinyl alcohol)hydrogel ordering electrical response composite hydrogel system,improve the comprehensive mechanics performance of the hydrogel,studies the rule of its strength and electrical response performance,and verify that the composite hydrogel under the effect of alternating electric field force coupling on the orientation of myocardial cells and nerve cells growth and value-added.The application of electrodynamic hydrogel in myocardial tissue repair and nerve repair provides theoretical and experimental basis. |
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