Controlled delivery of bovine serum albumin from carboxymethyl xanthan microparticles

Abstract

Bovine serum albumin (BSA)-loaded carboxymethyl xanthan (CMX) microparticles were prepared following gelation of sodium carboxymethyl xanthan (SCMX) gum with different concentrations (1–5%) of aluminium chloride (AlCl₃). The microparticles prepared using 1% AlCl₃ were subsequently coated with 0.5% aqueous solution of either SCMX gum or sodium alginate. Both uncoated and coated microparticles were characterized for entrapment efficiency, surface morphology, particle size, in vitro release and protein stability. The uncoated microparticles became non-spherical and the mean diameter was found to increase with increasing AlCl₃ concentration. Higher concentration of AlCl₃ decreased BSA entrapment efficiency of the uncoated microparticles from 86–61%. Furthermore, BSA entrapment in coated microparticles was found lower (78–79%) than uncoated microparticles prepared using 1% AlCl₃. Although, the uncoated microparticles released almost half of its content in NaCl-HCl buffer solution (pH 1.2) in 2 h, the alginate and xanthan coated microparticles did not liberate a substantial amount of entrapped protein within the same period and prolonged the release in PBS solution (pH 7.4) up to 10 and 12 h, respectively. The microparticles released the protein via diffusion and swelling of the polymer matrix. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that BSA integrity was well retained in the CMX microparticles.

Keywords::

• Carboxymethyl xanthan microparticles
• sodium alginate
• bovine serum albumin
• entrapment efficiency
• protein release

Acknowledgments

Declaration of interest: The authors report no conflicts of interest.