Enzyme powered self-assembly of hydrogel biosensor for colorimetric detection of metabolites

Enzyme powered self-assembly strategy is proposed in this work to construct enzyme-entrapped hydrogel biosensor, for simple, rapid, and colorimetric detection of metabolites. Specifically, the enzyme itself drives the assembly of hydrogel biosensor. The gelation process powered by enzyme is compatible for encapsulation of detection enzymes while retain their activities, so as to facilitate catalytic detection of specific metabolites with colorimetric signal readout. For convenience of the operation, the hydrogel biosensor has been further fitted in a test tube to construct a new kind of one-tube assay kit. For the proof-of-concept, assay kits for hydrogen peroxide (H2O2) and glucose have been testified. The linear detection ranges for H2O2 and glucose are 0.05–1.50 mM and 2–50 mM, the limit of detection (LOD) are 8.9 µM and 1.6 mM, and the entire assay time require only 1 min and 6 min, respectively. They exhibit high sensitivity and specificity both in test solution and real serum samples. Therefore, this one-tube colorimetric assay kit is promising for in home medical diagnosis and clinical routine rapid testing. Additionally, the hydrogel biosensor system may have universality for embedding other detecting enzymes, and enable many biomedical tests based on specific enzymes. [Display omitted] ●Enzyme powered self-assembly of hydrogel that also entraps other enzymes is proposed.●H2O2 can be the analyte in the hydrogel biosensor system rather than an initiator.●A one-tube assay kit is constructed for fast colorimetric detection of metabolites.●The hydrogel system is suitable for point-of-care assay in resource limiting areas.