Collagen conjugation to carboxyl-modified poly(3-hydroxybutyrate) microparticles: preparation, characterization and evaluation in vitro

https://doi.org/10.1007/s10965-022-03181-5

The objective of this study was to produce and characterize collagen conjugated poly(3-hydroxybutyrate) (P3HB) microparticles. The double emulsion solvent evaporation technique was used to fabricate biopolymer microparticles. Alkaline hydrolysis method was used for carboxylation of P3HB microparticles followed by collagen (type I) conjugation using 1-ethyl-3-(3-dime-thylaminopropyl) carbodiimide and N-hydroxysuccinimide cross linkers. The successful chemical modification of P3HB-MP surface was evidenced by XPS analysis and FTIR spectroscopy, confirming an increase in the number of carboxyl groups and covalent bonding of collagen on the surface of functionalized P3HB microparticles (Col-P3HB-MPs). The amount of collagen present on Col-P3HB-MPs microparticles was quantified by the Lowry method. The average diameter and zeta-potential of microparticles were found to be dependent upon the method of preparation. The absence of cytotoxicity of modified Col-P3HB-MPs to fibroblast NIH 3T3 cells in vitro was corroborated by results of MTT assay. Staining with the fluorescent dye showed enhanced adhesion of fibroblasts onto Col-P3HB-MPs compared to the unmodified P3HB-MPs.