text: Computational Method Based Optimization of Carbon Nanotube Thin Film Immunosensor for Rapid Detection of SARS CoV 2 Virus The recent global spread of COVID 19 stresses the importance of developing diagnostic testing that is rapid and does not require specialized laboratories In this regard nanomaterial thin film based immunosensors fabricated via solution processing are promising potentially due to their mass manufacturability on site detection and high sensitivity that enable direct detection of virus without the need for molecular amplification However thus far thin film based biosensors have been fabricated without properly analyzing how the thin film properties are correlated with the biosensor performance limiting the understanding of property performance relationships and the optimization process Herein the correlations between various thin film properties and the sensitivity of carbon nanotube thin film based immunosensors are systematically analyzed through which optimal sensitivity is attained Sensitivities toward SARS CoV 2 nucleocapsid protein in buffer solution and in the lysed virus are 0 024 fg mL sup 1 sup and 0 048 copies mL sup 1 sup respectively which are sufficient for diagnosing patients in the early stages of COVID 19 The technique therefore can potentially elucidate complex relationships between properties and performance of biosensors thereby enabling systematic optimization to further advance the applicability of biosensors for accurate and rapid point of care POC diagnosis 