High surface area sol–gel nano silica as a novel drug carrier substrate for sustained drug release

Among various carrier materials for drug delivery, silica has been found to be significant for loading and sustained release of the drug. In the present study, the antibiotic gentamicin was incorporated in various amounts on to a silica matrix, using a sol–gel subcritical drying route. Crack free silica rods with a length of 1–1.5 cm, diameter of 0.5 cm and density of 1.35 g/cm3 incorporated with gentamicin were obtained. The incorporation of gentamicin into the silica matrix was revealed by FTIR. The adsorption–desorption isotherms and pore size distribution were studied in detail. The drug elution patterns were analysed and show a biphasic mode of release. After the initial burst release, a constant release pattern is observed. A release value above the minimum inhibitory concentration (MIC) is always maintained. The amount of drug released is higher than that of many other bioactive ceramic materials. An attempt has been made to correlate the functional properties with the porosity features.

Graphical abstractCrack-free high surface area nano silica and gentamicin incorporated silica have been synthesized by adopting a sol–gel route. Attempts have been made to study the material property as well as drug release characteristics.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Sol–gel nano silica is found to be a novel drug delivery matrix. ► Controlled and sustained drug release is observed using nano silica as the matrix. ► Different drug loadings (10 mg/g silica, 20 mg/g silica, 30 mg/g silica) were attempted. ► Silica–gentamicin had a density of ∼1.35 g/cm3 with 1 cm length and 0.5 cm in diameter. ► Release value above the minimum inhibitory concentration is always maintained.