Synthesis and Structural Characterization of Bioactive PHA and γ-PGA Oligomers for Potential Applications as a Delivery System

Abstract

The (trans)esterification reaction of bacterial biopolymers with a selected bioactive compound with a hydroxyl group was applied as a convenient method for obtaining conjugates of such compound. Tyrosol, a naturally occurring phenolic compound, was selected as a model of a bioactive compound with a hydroxyl group. Selected biodegradable polyester and polyamide, poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P(3HB-co-4HB)) and poly-γ-glutamic acid (γ-PGA), respectively, were used. The (trans)esterification reactions were carried out in melt mediated by 4-toluenesulfonic acid monohydrate. The structures of (trans)esterification products were established at the molecular level with the aid of ESI-MS2 (electrospray ionization tandem mass spectrometry) and/or 1H NMR (nuclear magnetic resonance) techniques. Performed analyses confirmed that the developed method leads to the formation of conjugates in which bioactive compounds are covalently bonded to biopolymer chains. The amount of covalently bonded bioactive compounds in the resulting conjugates depends on the type of biopolymers applied in synthesis.

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) Production by Rhodospirillum rubrum Using a Two-Step Culture Strategy

“…Analyses were performed at 35°C using chloroform as a mobile phase at a flow rate of 1 mL/min. e instrument was calibrated with polystyrene narrow standards and then constructed a calibration curve [31].…”

The heterogeneous selective reduction of PHB as a useful method for preparation of oligodiols and surface modification

“…ESI-MS is used successfully for structural characterization PHA biopolyesters and other polyesters and copolyesters. 21,25,[30][31][32] Therefore, this technique was also used for the structural characterization of the obtained PHB oligodiols. Fig.…”

Mass spectrometry in bioresorbable polymer development, degradation and drug‐release tracking

“…Both MALDI and ESI MS, in some cases with the support of MS/MS and/or IM‐MS, have been used in the characterization of polymer conjugates, to confirm the effective functionalization and the success of the synthetic approch . The transesterification reaction of PHAs has been used as a strategic and simple tool for the synthesis of delivery systems for selected bioactive compounds, holding carboxyl or hydroxyl functionalities.…”

“…The transesterification reaction of PHAs has been used as a strategic and simple tool for the synthesis of delivery systems for selected bioactive compounds, holding carboxyl or hydroxyl functionalities. The structures of transesterification products were established at the molecular level by ESI‐MS/MS and 1 H NMR . The transesterification reaction of bacterial biopolymers with tyrosol was applied as a convenient method for obtaining polymer conjugates.…”