Biology subjects

de Guzman, R. C.

Publications and source records attributed to de Guzman, R. C..

2 recordsLinked to original sources

bioRxiv2018

Compressive strengths of PEG gels with glycerol and bioglass particles

Poly(ethylene glycol) (PEG)-based materials can potentially be used as biomechanical matrices for regenerative medicine implants including the replacement of intervertebral (IV) discs. Glycerol and other plasticizers (low-MW PEG, propylene glycol, and sorbitol) were added to the bulk PEG matrix, gelled using chemical and photochemical methods at different temperature and pressure settings, and compression properties acquired and analyzed. Incorporation of surface bioactive glass particles shortened the blood clotting time, while alginate and laponite additives improved the gels mechanical properties to 645 kPa compressive modulus, 12% yield strain, and 79 kPa yield strength. This IV disc-modeled system endured the cyclic loading and unloading test indicative of an elastic response; but required improvement of its biomechanical tolerance.

bioengineering↗

bioRxiv2018

PABA Release from Chitosan-PCL with Induced Electric Current

Controlled drug delivery systems such as the stimulation-based biomaterial scaffolds for sequestration and release of drugs offer safety and regulated therapeutic approach. In this study, the drug: para-aminobenzoic acid (PABA) was absorbed into a crosslinked chitosan and poly(caprolactone) (PCL) hydrogel and its release kinetics quantified under different conditions. It was experimentally-observed that the higher the pH (or the more basic the pH), the slower the PABA saturation release trended over time. At the acidic environment of pH 4, PABA was released the fastest, and enhanced by the degradation of chitosan-PCL gel. When a constant electric current of 0.6 mA sa applied, PABA release was induced at pH 10. However, at pH 7, PABA was stably-bound to the chitosan-PCL matrix, with or without the external current. The selective sequestration of PABA at basic pH and its stimulated release via electric current application can be further explored for clinical translatability.

bioengineering↗