A 3D μPAD based on a multi-enzyme organic-inorganic hybrid nanoflower reactor

This work reports on the development of a 3D microfluidic paper-based device (3D mu PAD) for glucose detection using organic-inorganic hybrid nanoflower technology to immobilize the bi-enzymatic system (glucose oxidase and horseradish peroxidase). The system is based on nanoflowerssupported on cellulose paper (the microreactor zone) coupled to 3,3',5,5'-tetramethylbenzidine (TMB) as the colorimetric probe in the detection zone. We used a digital camera for the quantitative analysis of glucose with the S coordinate of the HSV color space as the analytical parameter. Under optimal operational conditions, linearity was observed for glucose concentrations up to 300 mu M, with a detection limit of 15.6 mu M. The biosensor is reusable and remains stable for 75 days in conventional storage conditions. (C) 2015 Elsevier B.V. All rights reserved.