Gelatin/Polyethylene glycol/g-C3N4 hydrogel with olive oil as a sustainable and biocompatible nanovehicle for targeted delivery of 5-fluorouracil

<p> In this project, a novel, sustainable and pH-sensitive nanocomposite was designed for the targeted delivery of 5-fluorouracil (5-FU) against breast cancer cells. The nanodelivery system is based on graphitic carbon nitride (g-C3N4) coated with Gelatin (G)/Polyethylene glycol (PEG) biopolymers, and was prepared by W/O/W double emulsion technique using olive oil and span 80 surfactant. Successful loading of 5-FU into the nanovehicle was confirmed by infrared spectroscopy and X-ray diffraction analyses.</p>
<p>VDynamic light scattering corroborated the monodispersity of the nanocarriers, with a typical size between 250 and 300 nm. Scanning electron microscopy images revealed the homogeneity of the nanocomposite and its spherical shape. The average zeta potential was +35.4 mV, demonstrating the good stability of the nanocomposite. The drug loading (47%) and encapsulation efficiency (89%) were higher than those reported for other 5-FU nanocarriers.</p>
<p>A continuous and controlled 5-FU release from the nanovehicle was observed, and the release rate at pH 5.4 (simulating a cancerous environment) was higher than at pH 7.4 (physiological conditions). Kinetic studies suggested a diffusion controlled mechanism of 5-FU release from the nanocarrier in an acidic environment, while an anomalous transport prevails at neutral pH. The MTT assay revealed that G/PEG/g-C3N4 had a significant cytotoxicity on MCF-7 breast cancer cells. Flow cytometry indicated that G/PEG/g-C3N4/5-FU led to much higher apoptotic percentage than free 5-FU, while the free drug showed higher percentage of necroptotic cells.</p>