Immobilized cellulose nanospheres enable rapid antigen detection in lateral flow immunoassays

Abstract

Rapid diagnostic systems are essential in controlling the spread of viral pathogens and efficient patient management. The available technologies for low-cost viral antigen testing have several limitations, including a lack of accuracy and sensitivity. Here, we introduce a platform based on cellulose II nanoparticles (oppositely charged NPan and NPcat) for effective control of surface protein interactions, leading to rapid and sensitive antigen tests. Passivation against non-specific adsorption and augmented immobilization of sensing antibodies is achieved by adjusting the electrostatic charge of the nanoparticles. The interactions affecting the performance of the system are investigated by microgravimetry and confocal imaging. As a proof-of-concept test, SARS-CoV-2 nucleocapsid sensing was carried out by using saliva-wicking by channels that were stencil-printed on paper. We conclude that inkjet-printed NPcat elicits strong optical signals, visible after a few minutes, opening the opportunity for cost-effective and rapid diagnostic. Graphical abstract

Assessment of Cellulose Nanofiber-Based Elastase Biosensors to Inflammatory Disease as a Function of Spacer Length and Fluorescence Response

“…These nanocellulose materials are low-cost and have high surface areas, which allow for a greater number of binding sites for biological molecules with higher specificity and sensitivity. The number of functional properties uncovered for nanocellulose’s use as a sensor transducer surface has grown in recent years to include a range of mechanical and molecular design motifs and sensitivities. , Nanocellulose has been a platform for biosensing, drug delivery, and tissue engineering singularly or in combination with other molecules and polymers. − Recent improvements on the biocompatible properties of nanocellulose for use in biological systems have been reported, and numerous efforts continue to elucidate its potential as a wearable sensor for use in diagnostic, drug delivery and medical applications as “intelligent dressings”. , …”