Light-addressable photoelectrochemical sensors for multichannel detections of GPC1, CEA and GSH and its applications in early diagnosis of pancreatic cancer

Glypican-1 (GPC1) has been demonstrated to be a potential biomarker of pancreatic cancer, so ultrasensitive detection of GPC1 was important for the diagnosis of pancreatic cancer. In this paper, a photoelectrochemical (PEC) immunosensor based on gold nanoclusters (AuNCs) was developed for the first time for the ultrasensitive detection of GPC1. Then graphene oxide (GO) was introduced into AuNCs as a hybrid nanomaterial to improve the sensitivity. The results confirmed that GO increased the sensitivity by enhancing both the photoelectric properties and antibody loading properties. Finally, the PEC immunosensors for GPC1 detection achieved an optimal sensitivity (7.265 nA/decade) and an excellent limit of detection (LOD) of 15 pg/mL (S/N = 3). To provide more information for the early diagnosis of pancreatic cancer, multichannel light-addressable PEC sensors that achieved the simultaneous detection of biomacromolecules and biomicromolecules was further developed by AuNCs/GO based PEC immunosensors and carbon [email protected] silica beads ([email protected]) based PEC sensor. The simultaneous ultrasensitive detection of GPC1, carcinoembryonic antigen (CEA) and glutathione (GSH) were achieved by using this light-addressable PEC sensor. Finally, samples from pancreatic cancer models were detected, which verified the practicality and accuracy of the light-addressable PEC sensor in the evaluation and early diagnosis of pancreatic cancer.