Spinning disc processing technology: potential for large-scale manufacture of chitosan nanoparticles

Mass production of nanoparticles using a reliable cost-effective approach is a challenge in the pharmaceutical industry. In this study, the spinning disc processing (SDP) technology was used to fabricate chitosan nanoparticles, with a view to commercially produce chitosan nanoparticle-based drug delivery platforms. Chitosan solution (0.25%, w/v, in dilute acid, 27.5 mL, 1.5 mL/s) was intensely mixed with sodium tripolyphosphate solution (0.10%, w/v, in water, 20 mL, 1.1 mL/s) on the spinning disc (1000 rpm). Transmission electron microscopy and dynamic light scattering data confirmed that the nanoparticles (20 +/- 3 nm) were comparable in size and shape to those synthesised using a beaker and magnetic stirrer (31 +/- 13 nm). Larger nanoparticles (131 +/- 5 nm) were produced by increasing the chitosan and TPP feed concentrations to 0.5% and 0.125%, respectively. Drug loading further increased the size of the nanoparticles, with N-acetyl cysteine (NAC) having a greater effect (403 +/- 4 nm) than paracetamol (165 +/- 4 nm). Co-loading of both drugs increased the size of the particles to the micron range. In conclusion, the SDP is a robust technology capable of expanding the production of blank and drug-loaded chitosan nanoparticles for the biomedical and pharmaceutical industries.