Fabrication Of Micro/nano-structures Loading With Natural Bioactive Components Via Electrohydrodynamic Technique

Micro/nano-materials have been applied to energy,sensing,and biomedical fields,due to their distinctive characteristics in size distribution,specific surface area,and morphology,which further result in peculiar rheological and functional properties.This study focuses on encapsulating natural bioactive components,which are highly volatile or easily oxidized and degraded,within polymeric matrices via electrohydrodynamic techniques(electrospinning or electrospray),using high-voltage supply device.The main contents are listed as following:(1)Sodium alginate(NaAlg)particles loading with ganoderma lucidum spore polysaccharide(GLSP)were fabricated via electrospray technique.Particles with diameters ranging from 225 to 355 ?m were fabricated.In addition,changes to the environmental temperature enabled particles' shape and morphology variation.Transformation from conical to spherical geometries was observed,as a function of temperature,and crinkled surface topography became more prominent.Fourier transform infrared spectroscopy(FTIR)analysis indicated the successful and stable encapsulation of GLSP within NaAlg particle matrix,with little to no effect on the chemical structure integrity.Consistent values for loading capacity(LC)and encapsulation efficiency(EE)of GLSP within beads were obtained at all environmental electrospray temperatures.GLSP release varied based on intermolecular crosslinking,particle morphology and surface topography.(2)GLSP was encapsulated within zein prolamine(ZP)fibrous matrix via coaxial electrospinning process.Modified ZP/GLSP fibers with diameters ranging from 400 to 1700 nm were prepared using solvent components as the outer fluids during the co-electrospinning operation.LC and EE of GLSP were 15%and 85%,respectively,in all the groups.Distinctive release profiles were observed in different electrospinning groups,which are due to the influence of fiber size distribution and aspect ratio.CCK-8 assay analysis demonstrated good cytocompatibility for all test samples.Fluorescent images confirmed encapsulated GLSP and modified fibrous topography support extension and proliferation of fibroblast cells.(3)Orange essential oil(OEO)was encapsulated into ZP fibrous matrix via coaxial electrospinning process.Diameter of the prepared fibers distributed in the range of 750-1400 nm.FTIR analysis indicated the OEO component in ZP fibrous membranes.Additionally,various a-helix structures were detected in ZP solutions with different concentrations.Continuous and uniform fibers could be fabricated using ZP solution with high concentration,meanwhile,LC and EE of OEO were also improved.Results from the in-vitro cytotoxic test,observation of cell growth morphology,and antibacterial test proved the ideal biocompatibility and antimicrobial activity of the fabricated fibrous membranes.(4)ZP fibrous membranes loading with rose hip seed essential oil(REO)were fabricated via coaxial electrospinning process.FTIR,LC,and EE analysis confirmed the OEO in ZP matrix.In addition,for the application test,fibrous ZP/REO membranes exhibited a significant effect on prolonging the shelf-life of selected fruits through a facile and modifiable on-demand packaging process.This provides several benefits in reducing waste and increasing sustainability through a cost-effective and ambient condition process.In summary,this study achieved one-step preparation of composite polymeric materials,loading with natural bioactive components via electrohydrodynamic technique.By modulating the process and environmental parameters,micro/nano-materials with various morphologies,surface topographies,release profiles and physiochemical properties were obtained.Further study will focus on assessing the feasibility of applying the composite materials as drug delivery systems,bioscaffolds,and functionalized wound dressing.