5-Fluorouracil uptake and release from pH-responsive nanogels: An experimental and computational study

Chemotherapy is the treatment of choice in cancer therapy even though anti-tumor agents cause frequent and harmful effects on organs and tissues. Nanogels can efficiently improve cancer therapy by increasing the antineoplastic concentration in tumor sites and acting on cancer cells for prolonged periods without significantly affecting normal tissues. In this research, a pH-responsive Polyvinylpyrrolidone (PVP)-based nanogel for the controlled release of 5-Fluorouracil (5-FU) was developed. Nanogels were synthesized using gamma-radiation, and 5-FU was loaded into nanogels by physical entrapment. These formulations were characterized by spectroscopy techniques, electronic microscopy, and light scattering measurements. Drug loading and release from nanogels are strongly influenced by %PVP and irradiation dose. Simulations showed a higher drug-polymer affinity at low pH according to experimental loading values (encapsulation efficiency = 17% and drug loading = 83%). The sustained release profile responds to pH change from 1.2 to 7.4, increasing the release rate in acid conditions. Furthermore, nanogels have a negative surface charge, spherical morphology, and diameter of 41.0 +/- 0.9 nm. These properties show its potential as a nanocarrier of 5-FU for cancer treatment. (C) 2022 Elsevier B.V. All rights reserved.