Nanopot V1.0: A point of care electrochemical sensor prototype device for precise detection of tacrolimus in transplant patients

A miniaturized electrochemical sensor device prototype (NanoPot V1.0) encompasses with a portable potentiostat was developed for precise detection of tacrolimus, which is a critical immunosuppressant drug used for prevention of organ rejection in transplant patients. The developed NanoPot V1.0 prototype device combines a LMP91000 analog front-end with a ESP8266 microcontroller on a compact circuit board, along with a cylindrical well comprising of three electrode system with carbon cloth as working electrode. Notably, the chronoamperometric results from NanoPot V1.0 prototype device were very similar to those from a regular conventional CH Instruments potentiostat, which proved that he developed prototype device is accurate and reliable. The electrochemical behaviour of tacrolimus using NanoPot V1.0 prototype device was evaluated across a concentration range of 5 - 50 nM, which comes under clinically relevant levels. The prototype device showed excellent linearity with a detection limit comparable to standard laboratory equipment with excellent linearity (R 2 = 0.99) in tacrolimus quantification, with a detection limit comparable to standard laboratory equipment. Hence, this NanoPot V1.0 prototype device is bridging the gap between sophisticated laboratory-grade instruments and portable point-of-care (PoC) devices. This work represents a significant step towards developing a portable, sensitive, low-cost, and reliable PoC device for tacrolimus monitoring. This combination of miniaturized hardware and optimized electrochemical methods offers promising potential for point-of-care applications in transplant medicine and other broader bioanalytical fields. • An electrochemical sensor prototype (NanoPot V1.0) was developed for precise detection of tacrolimus • The prototype combines a LMP91000 analog front-end, ESP8266 microcontroller and a cylindrical well with three electrodes • The results from NanoPot V1.0 prototype device were very similar to conventional potentiostat • The NanoPot V1.0 prototype device was able to detect tacrolimus in range of 5 - 50 nM • The prototype device showed excellent linearity with a detection limit comparable to standard laboratory equipment