Analytical Sciences

Abstract − Analytical Sciences, 35(8), 903 (2019).

Sensitive Detection of Serum Creatinine Based on β-Cyclodextrin-Ferrocenylmethanol Modified Screen-printed Electrode
Xinmin HU,*1 Fang LIU,*2 Wenti LI,*3 Xiaochun WANG,*1 and Hongyu DENG*4
*1 Department of Laboratory Medicine, The Third Xiangya Hospital, Central South University, Changsha 410013, P. R. China
*2 Clinical Laboratory, Changsha Central Hospital, Changsha 410004, P. R. China
*3 Clinical Laboratory, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 440052, P. R. China
*4 Clinical Laboratory, Hunan Cancer Hospital & The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha 410006, P. R. China
Ferrocenylmethanol (Fc-OH) is included in β-cyclodextrin (β-CD) to form the β-CD-Fc-OH complex by host-guest supramolecular interaction. β-CD dissociates from the β-CD-Fc-OH complex due to the conversion of Fc-OH to Fc+-OH under a stimulus of oxidant. In our study, Fc-OH is oxidized after a series of enzymatic reactions of creatinine, which blocks the other means for oxidation of Fc-OH. And the background noise is reduced for testing for serum creatinine (sCr). The chronoamperometry signal for creatinine (with a constant potential –0.3 V vs. Ag/AgCl) increases linearly in the 1 – 1000 μM range, with a limit of detection as low as 0.5 μM. The amperometric potential of –0.3 V greatly prevents the interference of various redox substances in serum. The biosensor was used to test 120 clinical specimens and the results showed a linear correlation with the biochemical analyzer (R2 = 0.9885). The biosensor could be applied to clinical trials and offers good prospects for clinical sCr detection.