Microfluidic Preparation Of Alginate Composite Fibers And Study On Drug Release

Objective: Alginate fibres are widely used in medical dressing,drug delivery and tissue repair due to their excellent physicochemical properties and good biocompatibility.The aim of this thesis is to construct composite alginate fibres.The preparation method of alginate composite fibres,the application of drug-loading composite fibres and the tensile strength of the fibres were investigated.The experiments were divided into three parts.In the first part: the alginate composite fibres were prepared using microfluidic technology to investigate the influence of key factors on the preparation of alginate composite fibres.In the second part,alginate fibres doped with carboxymethyl cellulose(CMC)and encapsulated with drug-loaded microspheres were prepared to investigate the p H-responsive drug release performance of these fibres in the tumour cell environment.In the third part,the effect of the added material CMC on the tensile strength of the alginate gels was investigated.Methods: In the first part of this thesis,calcium alginate and gelatin methacrylate(Gel MA)composite hydrogel fibres were prepared using a coaxial capillary microfluidic device,and the effects of solution concentration and flow rate on fibre morphology were investigated using microscopic imaging methods.In the second part,based on the preparation process in the first part,p H-sensitive polymers were used as the matrix of drug-loaded microspheres for the loading and controlled release of the drug doxorubicin;and the p H-responsive drug release performance of these fibres was investigated using microscopic imaging and fluorescence imaging methods.The third part was based on electronic database search for keywords related to tensile strength,and after screening the literature,Meta-analysis was performed using Review Manager 5.4 software.Results: In the first part of the thesis,w/w droplet formation and the preparation of Gel MA microsphere@calcium alginate fibres,Gel MA@calcium alginate double-core hydrogel fibres and hollow calcium alginate fibres were achieved by fabricating a coaxial capillary microfluidic device,and the influence of the internal and external phase flow rate and concentration on the morphology of the fibres was obtained.In the second part,o/w droplets were prepared,and polymer microspheres of uniform size and spacing could be formed inside the fibres by solvent volatilisation;the experimental results confirmed that the composite fibres could produce microsphere degradation and morphological changes under different p H conditions.In the third part,Meta-analysis confirmed that CMC in alginate hydrogel fibres could enhance the tensile strength of the fibres.The concentration of Gel MA solution,the mass of GO and the concentration of sodium alginate solution were all sources of heterogeneity.Conclusions: For Gel MA microspheres@calcium alginate fibers,the size of microspheres increased with the concentration of Gel MA solution and decreased with the concentration of sodium alginate solution;for hollow calcium alginate hydrogel fibers,the diameter of the outer fibers increased with the flow rate of sodium alginate and the diameter of the inner liquid core decreased;the diameter of both the outer fibers and the inner liquid core increased with the concentration of sodium alginate.2.For the drug-loaded composite fibres,the drug-loaded microspheres were able to release drugs selectively in the tumour cell environment and CMC enhanced the fibres’ ability to respond to environmental p H.3.The addition of CMC enhanced the tensile strength of the alginate gels and the heterogeneity was derived from three factors.