Preparation of protein-loaded nanoparticles based on polysuccinimide-oleylamine for sustained protein release: A two-step nanoprecipitation method.

Currently, the treatment for acute disease encompasses the use of various biological drugs (BDs). However, the utilisation of BDs is limited due to its rapid clearance and non-specific accumulation in unwanted sites which results in a lack of therapeutic efficacy accompanied with adverse effects. While nanoparticles were considered a good candidate to resolve this problem, some available polymeric carriers for these BDs are mainly designed for long-term sustained release. Thus, there is a need to explore new polymeric carriers for diseases' acute phase that requires sustained release of BDs in a short period such as thrombolysis and infec-tion. Poly(succinimide)-oleylamine (PSI-OA), a biocompatible polymer with tuneable dissolu-tion profile, represents a promising strategy to load BD for sustained release within a 48-hour period. In this work, we developed a two-step nanoprecipitation method to load the model protein (e.g. bovine serum albumin (BSA) and lipase) with PSI-OA. The characteristics of the nanoparticles were assessed based on various loading parameters, such as concentration, stir-ring rate, flow rate, volume ratios, dissolution, and the release of the protein. The optimised NPs displayed a size within 200 nm that is suitable for vasculature delivery to the target sites. These findings suggest that PSI-OA can be employed as a carrier for BDs for applications that require sustained release in a short period.