Lateral flow immunoassay based on electrospun cellulose acetate nanofibrous membrane for C-reactive protein

Lateral flow immunoassay (LFA) is an attractive detection tool due to its low cost, compact size, and ease of use. However, the inconsistent porosities and pore sizes in commercial lateral flow nitrocellulose (NC) membrane materials often lead to false signals caused by unwashed conjugate particles trapped within the structure and impurities absorbed due to high surface activity. Cellulose acetate (CA) membranes have potential for LFA applications as an environmental-friendly alternative, but their preparation process still needs to be optimized specifically for LFA. In this study, we present, for the first time, an electrospun CA fibrous membrane for LFA, replacing commercial NC or CA membrane, for the detection of C-reactive protein (CRP). The CA membrane was designed and prepared by electrospinning, subsequently integrated into a lateral flow device, and the effects of precursor powder, electrospinning distance, and electrospun solution usage on the microstructure and LFA signals were systematically investigated. The electrospun CA membrane exhibited a sixfold faster flow time than a commercial CA membrane for CRP detection, while maintaining comparable sensitivity and reducing false signals relative to commercial membranes. Clinical tests further validated the potential of our electrospun CA membrane by achieving accurate and reliable CRP detection. This work provides fundamental knowledge for developing lateral flow devices and highlights the potential for a wide range of applications in detecting protein biomarkers for clinical diseases.