Alam I.Lertanantawong B.Sutthibutpong T.Punnakitikashem P.Asanithi P.Mahidol University2023-06-182023-06-182022-05-01Biosensors Vol.12 No.5 (2022)https://repository.li.mahidol.ac.th/handle/20.500.14594/83744A tryptophan (Trp) sensor was investigated based on electrochemical impedance spectroscopy (EIS) of a molecularly imprinted polymer on a lysozyme amyloid fibril (MIP-AF). The MIP-AF was composed of aniline as a monomer chemically polymerized in the presence of a Trp template molecule onto the AF surface. After extracting the template molecule, the MIP-AF had cavities with a high affinity for the Trp molecules. The obtained MIP-AF demonstrated rapid Trp adsorption and substantial binding capacity (50 µM mg−1 ). Trp determination was studied using non-Faradaic EIS by drop drying the MIP-AF on the working electrode of a screen-printed electrode. The MIP-AF provided a large linear range (10 pM–80 µM), a low detection limit (8 pM), and high selectivity for Trp determination. Furthermore, the proposed method also indicates that the MIP-AF can be used to determine Trp in real samples such as milk and cancer cell media.Biochemistry, Genetics and Molecular BiologyArticleSCOPUS10.3390/bios120502912-s2.0-851302010222079637435624592