Electrochemical sensor based on Cu(II) coordination covalent organic framework for ultra-sensitive and specific detection of paclitaxel

Abstract

In this study, a MWCNT/COF@Cu(II)/GCE electrochemical sensor based on Cu(II)-coordinated covalent organic framework (COF) was developed for the efficient detection of paclitaxel (PTX) content in Taxus cuspidata suspended cells extract. Specifically, a COF was constructed through an ambient temperature synthesis strategy, utilizing 4,4′,4′’-(1,3,5-triazine-2,4,6-triyl)trisaniline (TTA) and 2,6-pyridinedialdehyde (PDA) as the fundamental building blocks. Subsequently, Cu(II) was immobilized on the COF surface by pyridinic and imine groups, followed by integration with MWCNT, to fabricate an electrode modification material MWCNT@COF@Cu(II) with enhanced charge transfer kinetics and electrocatalytic activity. The results showed that the modified electrode significantly improved the electrochemically active area and electron transport capacity, and had excellent electrochemical detection performance of PTX. The sensor’s detection range is 0.5 to 20 μM, and the PTX detection limit is 1.6 nM. Furthermore, quantum chemical simulations reveal the high conductivity mechanism on MWCNT/COF@Cu(II)/GCE and the possible electrooxidation mechanism for PTX. Finally, the sensor showed superior detection performance in the actual sample detection, with a recovery rate of 98.22 %–103.03 %. These results suggest that MWCNT@COF@Cu(II)/GCE has the potential to effectively detect PTX from T. cuspidata suspended cell extract.