Design and scale-up of amorphous drug nanoparticles production via a one-step anhydrous continuous process
Polymeric nanoparticle drug delivery systems are increasingly viewed as crucial building blocks for efficacious treatments of disease conditions. However, production methods at commercially practical scales pose a significant challenge for successfully translating such technology. This paper describes a novel, anhydrous, twin-screw extrusion (TSE) platform-based technology to overcome the issues associated with developing and scale-up production of nanoparticulate drug delivery systems. With polyol as the process medium, the proposed TSE platform enables the encapsulation of the drug and reduction of particle size in a one-step process without the requirement for organic solvents or water. pH-responsive nanoparticle drug delivery of two nonsteroidal anti-inflammatory drugs, naproxen, and celecoxib, was successfully produced using the TSE process. Remarkably, these resulted in nanoparticles with sizes ranging from 80 to 240 nm, up to 98 % drug encapsulation efficiency, and maximum production throughput of 400 g/hour. pH-responsive drug release for both naproxen and celecoxib was also achieved: immediate drug release with enhanced solubility was obtained for naproxen-Eudragit®E nanoparticles (6 times higher) at pH 1.2 and celecoxib-HPMCAS nanoparticles (15 times higher) at pH 6.8, whilst sustained drug release was achieved for naproxen-Eudragit®E nanoparticles at pH 6.8 and celecoxib-HPMCAS nanoparticles at pH 1.2. We expect this platform technology to streamline the development and scale-up production of various polymeric nanoparticle drug delivery systems.