Unlocking the power of chirality: Surface nanoarchitectonics of modified halloysite nanotubes for enantioselective recognition

Developing cost-effective electrode materials with high performance for enantioselective recognition is rapidly gaining attention. In this work, we harness the unique physicochemical properties of halloysite nanotubes (HNTs) as innovative electrode platforms for chiral discrimination. We functionalized HNTs with an enantiopure oligomer based on thiophene units via chemical oligomerization using FeCl₃ as an oxidizing agent. The successful functionalization of the HNTs with the oligomer was further confirmed by both solid state ¹³C NMR and zeta potential studies (from -20.0 ± 1.5 mV to -12.4 ± 3.0 mV after modification). The resulting composite materials (oligo-(S)- and oligo-(R)- modified HNTs) demonstrated remarkable enantioselective recognition capabilities in terms of peak potential values (560-650 mV) when testing the enantiomers of DOPA, a chiral drug of pharmaceutical interest. These findings highlight the potential of HNT-based modified electrodes as a novel class of chiral electrochemical sensors, paving the way for advanced applications in enantioselective analysis.