In-situ grown NiFeLDH nanosheets over nitrogen rich amorphous carbon nanotubes: An electrochemical sensing platform for the detection of depression biomarker

In this work, intrinsic conductivity mismatch of NiFe layered double hydroxide (NFL) catalysts and agglomeration of nanosheets were addressed by introducing N doped carbon nanotubes (NCNTs) which improves catalytic activity. Using a one-step wet chemical process, CNT-supported NiFeLDH nanosheets (NFL/NCNT_x, x = 20, 50 and 100) were effectively created. This work delves into the lower level sensitive electrochemical detection of serotonin (5-HT) by utilizing synergy of CNT and LDH. The modified NFL/NCNT exhibits better electrochemical activity, appreciable sensitivity and spanned a concentration range of 0.01–400 μM with detection limit stood at 1.2 nM due to the plethora of electrochemical active surface area, remarkable conductivity and appreciable stability. Impressively, 96.0–96.8 % and 96.7–97.2 % recovery rates achieved in human urine and serum samples were well close to HPLC data, signifying its feasibility for real-time monitoring. The operational stability of the proposed sensor retained up to 89.13 % for 6 weeks. The present study highlights that tailoring NFL-NCNT heterojunction is an important strategy for the development of active and stable sensing platform.