π‐Conjugated Copper Phthalocyanine Nanoparticles as Highly Sensitive Sensor for Colorimetric Detection of Biomarkers
Fan Chen, Huang Zhu, Ning Lv, Qian Li, Tian Ma, Liyun Wang, Mi Zhou, Sujiao Cao, Xianglin Luo, Chong Cheng
Abstract
Abstract Though numerous nanomaterials with enzyme‐like activities have been utilized as probes and sensors for detecting biological molecules, it is still challenging to construct highly sensitive detectors for biomarkers using polymeric materials. Benefiting from the π‐d delocalization effect of electrons, excellent metal‐chelating property, high electron transferability, and good chemical stability of π‐conjugated phthalocyanine, the design of the copper phthalocyanine‐based conjugated polymer nanoparticles (Cu‐PcCP NPs) as a colorimetric sensor for a variety of biomarkers is reported. The Cu‐PcCP NPs are synthesized through a simple microwave‐assisted polymerization, and their chemical structures are thoroughly characterized. The colorimetric results of Cu‐PcCP NPs demonstrate excellent peroxidase‐like detecting activity and also great substrate selectivity than most of the reported Cu‐based nanomaterials. The Cu‐PcCP NPs can achieve a detection limit of 4.88 μM for the H 2 O 2 , 4.27 μM for the L‐cysteine, and 21.10 μM for the glucose via a cascade catalytic system, which shows comparable detecting sensitivity as that of many earlier reported enzyme‐like nanomaterials. Moreover, Cu‐PcCP NPs present remarkable resistance to harsh conditions, including high temperature, low pH, and excessive salts. These highly specific π‐conjugated copper‐phthalocyanine nanoparticles not only overcome the current limitation of polymeric material‐based sensors but also provide a new direction for designing next‐generation enzyme‐like nanomaterial‐based colorimetric biosensors.