Nanofluidic ion rectification sensor for enantioselective recognition and detection

Enantiomer identification is of paramount industrial value and physiological significance. Construction of sensitive chiral sensors with high enantiomeric discrimination ability is highly desirable. In this work, a chiral covalent organic framework/anodic aluminum oxide (c-COF/AAO) membrane was prepared for electrochemical enantioselective recognition and sensing. Benefiting from the remarkable asymmetry, the as-prepared nanofluidic c-COF/AAO presents a distinct ion current rectification (ICR) characteristic, enabling sensitive bioanalysis. In addition, owing to the large surface area, high chemical stability and perfect ion selectivity of chiral COF, the prepared c-COF/AAO membrane presents exceptionally selective mass transport and thereby enables excellent chiral discrimination for S-/R-Naproxen (S-/R-Npx) enantiomers. It is especially noteworthy that the detection limit is achieved as low as 3.88 pmol/L. These results raise the possibility for a facile, stable and low-cost method to carry out sensitive enantioselective recognition and detection. A chiral covalent organic framework/anodic aluminum oxide (c-COF/AAO) membrane was prepared for electrochemical enantioselective recognition. Benefiting from the remarkable asymmetry, the nanofluidic c-COF/AAO membrane presents a distinct ion current rectification (ICR), enabling sensitive bioanalysis. In addition, owing to the large surface area, high chemical stability and perfect ion selectivity of chiral COF, the prepared c-COF/AAO membrane presents exceptionally selective mass transport and thereby enables excellent chiral discrimination for S-/R-Naproxen (S-/R-Npx) enantiomers. [Display omitted]