Conductive 2D phthalocyanine-based metal-organic framework as a photoelectrochemical sensor for N-acetyl-L-cysteine detection

The thiol compound N-acetyl- L -cysteine (NAC) functions as an antioxidant in protecting cells from cytotoxic poisoning and has numerous therapeutic applications. Therefore, its quantification holds significance in clinical research. Photoelectrochemical analysis is a fast, low-cost, and efficient technique for such a purpose. However, it is challenging to use it directly for NAC detection. Therefore, in this study, conductive 2D octa-hydroxy-substituted nickel(II) phthalocyanine copper metal-organic framework (NiPc-Cu MOF) as a photoelectrochemical (PEC) sensor was successfully fabricated for enhanced room-temperature NAC determination. As NAC is able to interact with Cu compounds, the NiPc-Cu MOF was used as a PEC sensor for sensitive NAC identification. The photocurrent produced by NiPc-Cu MOF was attenuated after NAC interaction. Under optimal conditions, the sensor accurately monitored NAC concentrations ranging from 0.0125 to 42.5 μM with an ultra-low limit of detection (5.2 nM). Notably, the methodology provides a straightforward and powerful way to efficiently determine NAC in a highly selective manner, which could be significantly beneficial in pharmaceutical process monitoring and quality control. • Synthesis of 2D octa-hydroxy-substituted Nickel(II) phthalocyanine-Copper MOF. • NiPc-Cu MOF/ITO sensor successfully used for the first time in photoelectrochemistry. • Highly selective determination of N-acetyl- L -cysteine (NAC) via the formation of Cu-S bond. • NiPc-Cu MOF/ITO sensor exhibited ultra-high sensitivity with a LOD of 5.2 nM. • Successful quantitative analysis of different dosages of NAC.