A reaction-based fluorescence for accurately monitoring β-Gal in PBMCs, living cells and BALB/c nude mice

β-galactosidase (β-Gal), as a key biomarker closely associated with colorectal cancer, holds an indispensable position in the early diagnosis and therapeutic efficacy assessment of cancer. MQ-βGal achieves highly specific targeted binding with β-Gal and demonstrates outstanding comprehensive performance, featuring a broad linear response range, high detection sensitivity and robust interference resistance. Benefiting from MQ-βGal's favorable biocompatibility and low cytotoxicity, it has been successfully applied to real-time tracking of dynamic β-Gal concentration changes within living cell. Building upon this, MQ-βGal's application has been further extended to the in vivo level, successfully achieving in situ monitoring of endogenous β-Gal activity in BALB/c nude mouse models, thereby validating its suitability for in vivo biological imaging. More significantly, clinical sample validation experiments demonstrate that MQ-βGal effectively distinguishes biological samples from healthy individuals and colorectal cancer patients, specifically identifying abnormal β-Gal expression patterns during colorectal cancer development. These findings fully highlight the potential application value and translational prospects of this fluorescent diagnostic system in the early clinical diagnosis and disease assessment of colorectal cancer.