Highly specific lubricin-lectin electrochemical sensor for glycoprotein cancer biomarker detection

Electrochemical glycoprotein sensors have proven to be a great alternative for the detection and characterization of cancer, therapeutic design, and monitoring. A combination of the glycoproteins lubricin (LUB) and peanut agglutinin (PNA) has been successfully implemented for the detection of tumour-associated short glycans directly in bodily fluids, e.g. whole blood. However, such an approach has so far only been studied using a surface-bound redox mediator engineered with the recognition element, PNA. In this paper, we extend the lubricin-peanut agglutinin (LUB-PNA) interface for monitoring glycan binding interactions using redox species in solution. Cy-clic voltammetry and electrochemical impedance spectroscopy measurements using the LUB-PNA interface showed that faradaic electron transfer of ferrocyanide redox species in solution is altered in presence of the glycoprotein containing cancer-associated T-antigen glycoprotein (asialofetuin, ASF), while it does not alter in presence of the sialylated glycoform of ASF, fetuin (FET), bovine serum albumin (BSA) and Tn-antigen. The limit of detection (LoD) of ASF is 39 nM in PBS. In addition, this highly specific LUB-PNA sensor allows for the detection of ASF in human blood.

Automated summary

Electrochemical glycoprotein sensors are an effective tool for cancer detection, therapeutic design, and monitoring. The combination of lubricin (LUB) and peanut agglutinin (PNA) has been used to directly detect tumor-associated short glycans in bodily fluids. This study extends the use of the LUB-PNA interface to monitor glycan binding interactions using redox species in solution. By measuring cyclic voltammetry and electrochemical impedance spectroscopy, the study reveals the altered behavior of ferrocyanide redox species in the presence of cancer-associated T-antigen glycoprotein. The sensor also enables the detection of ASF in human blood.