蛋白酪氨酸磷酸酶1B活性的光电化学-石英晶体微天平双模式检测OA

In this study,a dual-mode sensing platform combining photoelectrochemical(PEC)and quartz crystal microbalance(QCM)techniques was developed for highly sensitive assay of protein tyro-sine phosphatase 1B(PTP1B)activity.The sensing platform employed a porous anatase/rutile TiO2 heterojunction loaded with phosphotungstic acid(A/R-TiO2@HPW)as the photocurrent-responsive material.The PTP1B-targeted phosphorylated-peptide was immobilized on the QCM gold-coated quartz crystal(Au electrode)through the specific binding between TiO2 and phosphate groups,and silicon dioxide(SiO2)nanospheres were introduced to enhance spatial hindrance,thereby suppress-ing the initial photocurrent.Upon PTP1B-catalyzed dephosphorylation of the peptide,both the pep-tide and SiO2 nanospheres were released from the Au electrode,leading to photocurrent recovery along with a significant change in the QCM resonant frequency,thus enabling sensitive PEC-QCM dual-mode detection of PTP1B activity.This strategy integrates PEC and QCM modes and effectively avoids false-positive interference through dual-mode self-calibration.Moreover,by replacing the sub-strate,the developed sensing platform can be extended into a universal detection platform for protein phosphatases.Given the critical role of PTP1B in insulin signaling and metabolic diseases,this study provides a potentially reliable tool for related pathological research,drug screening,and clini-cal diagnosis.