Technologies

Researchers at UC San Diego have developed a disposable electrochemical chip platform for on-the-spot monitoring of multiple diabetes-relevant biomarkers found in human blood, saliva and interstitial fluid. In an exemplary embodiment, a dual‐marker biosensor integrates enzyme and antibody‐based assays for simultaneous electrochemical measurements of insulin (I) and glucose (G). Simultaneous G/I sensing was realized by addressing key fabrication and operational challenges associated with the different assay requirements and surface chemistry. The I immunosensor relies on a peroxidase‐labeled sandwich immunoassay, while G is monitored through reaction with glucose oxidase. The dual diabetes biomarker chip offers selective and reproducible detection of picomolar I and millimolar G concentrations in a single microliter sample droplet within less than 30 min, including direct measurements in whole blood and saliva samples.

A major goal in disease screening, diagnosis, and control has been to develop bioassay platforms capable of simultaneous measurements of different analytes in a single assay. Significant advances toward multiplexed biomarker detection chips based on either immunoassays or enzymatic bioassays have thus been reported. However, the combination of enzymatic and immunoassay sensing into a single disposable system has hitherto not been addressed.