One‐Pot Synthesis of Size‐Controlled Poly(cyclotriphosphazene‐co‐hesperetin) Microspheres and Their Properties as Drug Delivery Carriers

Abstract

In this study, cross‐linked poly(cyclotriphosphazene‐co‐hesperetin) (PCTPHP) microspheres were synthesized by the reaction of hexachlorocyclotriphosphazene (HCCP) with hesperetin (HSP). Fourier transform infrared (FT‐IR) spectroscopy was used to confirm the successful preparation of the PCTPHP microspheres. The cross‐linking density of the prepared PCTPHP microspheres was examined by electron paramagnetic resonance (EPR) spectroscopy. The results showed that the increased HSP mole might be more suitable to cross‐link with HCCP in high density. The thermal properties, particle size distribution, morphology and crystalline nature of PCTPHP microspheres were investigated by thermogravimetric analysis (TGA), dynamic light scattering (DLS), scanning electron microscope (SEM) and X‐ray diffraction (XRD). The prepared PCTPHP‐3 microspheres were used as drug carriers. The 5‐fluorouracil (5‐FU) was loaded on the microspheres and their in vitro release behavior was observed at two different pH values. The results showed a controlled release of 5‐FU from the PCTPHP‐3/5‐FU in both basic and acidic mediums up to 216 h. The results showed that the PCTPHP microspheres might play a vital role as drug carriers in cancer therapy.