A Cu2+-assisted fluorescence switch biosensor for detecting of coenzyme A employing nitrogen-doped carbon

Herein, a simple and sensitive Cu2+-assisted fluorescence switch biosensor for the detection of coenzyme A (CoA) was proposed by employing nitrogen-doped carbon dots (N-CDs). N-CDs were successfully synthesized by sodium alginate and melatonin via pyrolysis. The as-prepared N-CDs were spherical with an average diameter of 2.8 nm and exhibited blue emission (lambda(em) = 480 nm, lambda(ex) = 360 nm) with a high fluorescence quantum yield of 50.2%. The intense blue emission of the N-CDs could be effectively quenched by copper ions through the formation of the NCDs/Cu2+ complex. With the introduction of CoA, a more stable CoA/Cu2+ complex formed, leading to the fluorescence recovery of N-CDs. Based on this strategy, CoA could be sensitively and selectively detected with a good linear relationship in the range of 0.02-5.00 mu M and with a detection limit of 12 nM. In addition, this sensor was applied for CoA detection in human serum samples with satisfactory recovery. The results showed great potential towards advancing applications in CoA-dependent bioresearch.

Automated summary

A Cu2+-assisted fluorescence switch biosensor utilizing nitrogen-doped carbon dots (N-CDs) was developed for the detection of coenzyme A (CoA), showing a sensitive and selective detection with a good linear relationship and a low detection limit. The sensor could successfully detect CoA in human serum samples, demonstrating great potential for CoA-dependent bioresearch applications.