Our focus is on using beta cyclodextrin (βCD) to electrochemically detect cortisol; cortisol is a hydrophobic molecule that is a vital hormone, and cortisol is involved in the immune system, metabolism, heart health, and overall body balance. Cyclodextrins, characterized by a hydrophobic inner cavity and a hydrophilic outer surface, emerge as promising molecular receptors for detecting hydrophobic molecules. Notably, βCD and cortisol can form host/guest inclusion complexes. Building on our success in detecting cortisol with βCD in previous static cell experiments [1], herein we introduce innovations to further improve our methodology by employing an automated flow cell system. The transition to automation offers advantages such as repeated runs for obtaining more reproducible data and the elimination of human interactions and considerations, leading to an increased number of experiments. Our efforts, including the utilization of a ten-way multi-position valve and a pump for solution transfer, were crucial for enhancing the accuracy, stability, and reproducibility of cyclodextrin-mediated biosensors in automated flow cell systems. The automation process did encounter challenges, particularly with pump control, necessitating manual pauses before electrochemical measurements. Additionally, issues related to bubbles arose, prompting the search for the optimal flow rate and the utilization of a degasser. The ultimate goal is to optimize sensor stability, sensitivity, and reproducibility, contributing to the advancement of cortisol detection with the automated cyclodextrin-mediated biosensors.Research supported by New Hampshire- INBRE through an Institutional Development Award (IDeA), P20GM103506, from the National Institute of General Medical Sciences of the NIH. Support was also provided by a National Science Foundation EPSCoR award (#2119237), BIO-SENS.[1] Z. Panahi, T. Ren, and J. M. Halpern, “Nanostructured Cyclodextrin-Mediated Surface for Capacitive Determination of Cortisol in Multiple Biofluids,” ACS Appl. Mater. Interfaces, vol. 14, no. 37, pp. 42374–42387, Sep. 2022, doi: 10.1021/acsami.2c07701.
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