Biocompatible macro, micro and nano scale guar gum hydrogels and their protein absorption capacity

Abstract

This work describes the preparation and characterization of different guar gum (GG) hydrogels at different sizes to be used for protein absorption. GG macrogels and micro/nanogels were synthesized through chemical crosslinking via bulk polymerization and reverse micelle microemulsion techniques, respectively, and high yields, for example, 94 ± 4% and 91 ± 6% were obtained. GG micro/nanogels with spherical shape and smooth surface were separated in the range of 1–10 µm and 300–900 nm by the filtration process. The blood compatibility assay revealed that GG micro/nanogels were blood compatible up to 2 mg/mL concentration with maximum 1.59 ± 0.97% hemolysis ratio and minimum 84 ± 2.6% blood clotting index. Furthermore, the cytotoxicity assay demonstrated that linear GG inhibited cell viability at ≥250 µg/mL concentrations, whereas no significant difference was obtained up to 1000 µg/mL concentration when compared to the control groups statistically (p > .05). It was further demonstrated that GG micro/nanogels retain great potential to absorb hemoglobin and lysozyme with 59 ± 7 and 20 ± 8 mg/g absorption capacity at pH 7.4. Furthermore, the absorption capacity of the negatively charged GG micro/nanogels could be augmented by adjusting the pH conditions down to the isoelectric point (IP) of the proteins.