Synthesis, characterization, hydrolytic degradation, mathematical modeling and antibacterial activity of poly[bis((methoxyethoxy)ethoxy)phosphazene] (MEEP)

Abstract

Applications of polyphosphazenes are gaining attention in biomedical industry due to their unique characteristics of being easily degradable. This has been achieved by the replacement of chloro groups with appropriate nucleophiles. In our present study, we have synthesized a degradable polyphosphazene by the replacement of chloro groups with 2-(2-methoxyethoxy) ethanol having controlled molecular weight. Synthesis of poly[bis((methoxyethoxy)ethoxy)phosphazene] (MEEP) is carried out in two steps. First step involves the synthesis of polydichlorophosphazenes (PDCP) from hexachlorocyclo triphosphazene using AlCl3 as catalyst by ring opening polymerization. In the second step, PDCP chlorines are substituted by 2(2-methoxyethoxyethoxy) moiety. The structure of synthesized MEEP is confirmed by phosphorous-31 nuclear magnetic resonance (31P NMR) and hydrogen-1 nuclear magnetic resonance (1H NMR). Molecular weight, molar mass distribution and polydispersity index are determined by Gel Permeation Chromatography (GPC). In vitro, hydrolytic degradation of the MEEP is carried at 37 °C in phosphate-buffered saline (PBS) with neutral, basic and acidic media. Moreover, the experimental data are demonstrated by statistical and graphical methods. The values of the coefficient of determination (R2) were found to be 0.9987, 0.9856 and 0.9359, respectively. The values of the coefficient indicate that the workability of the theoretically fitted models is good. Antibacterial activity of the synthesized polyphosphazene is evaluated against methicillin-resistant Staphylococcus aureus. The potential applications of present study are applicable for biomedical applications such as drug delivery.