An in situ fluorescent copolymer dots-based kit for the specific detection of monoamine oxidase-A in cell/tissue/human prostate cancer

Currently, the development of simple, fast, low-cost, and environmentally friendly MAO-A specific detection methods remains a huge challenge. Herein, a simple in situ fluorescent copolymer dots (FCDs)-based kit is constructed for the specific detection of monoamine oxidase-A in cell, tissue and human prostate cancer. The developed kit is depended on the high reaction activity between epinephrine and polyethyleneimine to form FCDs and the selective catalyzing activity of MAO-A on epinephrine. The gained FCDs are identified and characterized by high-resolution TEM, absorption and fluorescence spectrum. The present kit achieves highly sensitive detection of MAO-A with a limit of detection (LOD) of 20 ng/mL as well as screening of inhibitor with an IC50 (the concentration responding to 50% inhibition) of 1.071 μM by using clorgyline as a model. The MAO-A and MAO-B as the two isoforms of MAO are discriminated successfully, demonstrating the excellent selectivity of our kit. Noteworthy, the proposed method is applicable for measuring MAO-A not only from serum samples, but also for endogenous MAO-A in cells, mouse tissues and human prostate tumors with satisfied results. The proposed kit will be a great potential tool for human prostate cancer (PCa) diagnosis and the development of anti-PCa drug screening.