Preparation of Boron Carbide Biopolymer Systems with One Step Sol–Gel Synthesis for pH-Controlled Drug Delivery

A new pH-sensitive polysaccharides-based boron carbide sol–gel system including Donepezil (DNP) was prepared. The hybrid sol–gel systems were synthesized with the addition of biopolymers such as β-cyclodextrin (β-CD), dextrin (Dex), shellac wax (Wax), also polyethylene glycol (PEG) to cubic boron carbide (BC) by coupling of triethyl orthosilicate (TEOS) and Donepezil. The release of the donepezil from these hybrid sol–gels, was studied by using buffers at various pH levels such as 2.2, 4.0, 6.0, 7.4 and 8.6. Fluorescence spectroscopy was used for the measurement of DNP release. The excitation and emission wavelengths at each pH level were recorded at 335 nm and 387 nm. The release percentages of the donepezil were measured by regression equation curves. Results showed that DNP-loaded BC-TEOS and BC-TEOS-β-CD released the maximum amount of DNP as 14.88% and 19.03% at 74 of pH after one hour, respectively. The BC-TEOS-Wax with 80.84% was more available at a pH of 8.6 for the prolonged release of DNP at the end of 120 min. The ζ–potential indicates that the surface charge of the particles increased from − 36.56 to – 48.74 mV after modification of boron carbide-TEOS. The new sol–gel boron carbide systems were characterized by using Fourier transform infrared spectroscopy (FTIR), Transmission electron microscopy (TEM), and Scanning electron microscopy (SEM) analysis.