Paper-based glucose biosensing system utilizing a smartphone as a signal reader

Abstract

A simple paper-based optical biosensor for glucose monitoring was developed. As a glucose biosensing principle, a colorimetric glucose assay, using glucose oxidase (GOx) and horseradish peroxidase (HRP), was chosen. The enzymatic glucose assay was implanted on the analytical paper-based device, which is fabricated by the wax printing method. The fabricated device consists of two paper layers. The top layer has a sample loading zone and a detection zone, which are modified with enzymes and chromogens. The bottom layer contains a fluidic channel to convey the solution from the loading zone to the detection zone. Double-sided adhesive tape is used to attach these two layers. In this system, when a glucose solution is dropped onto the loading zone, the solution is transferred to the detection zone, which is modified with GOx, HRP, and chromogenic compounds through the connected fluidic channel. In the presence of GOx-generated H 2 O 2 , HRP converts chromogenic compounds into the final product exhibiting a blue color, inducing color change in the detection zone. To confirm the changes in signal intensity in the detection zone, the resulting image was registered by a digital camera from a smartphone. To minimize signal interference from external light, the experiment was performed in a specifically designed light-tight box, which was suited to the smartphone. By using the developed biosensing system, various concentrations of glucose samples (0-20 mM) and human serum (5-17 mM) were precisely analyzed within a few minutes. With the developed system, we could expand the applicability of a smartphone to bioanalytical health care.

Colorimetric Detection of Glucose in Biological Fluids Using Toner-Based Microzone Plates

“…The poor uniformity is caused due to the weak interaction between enzymes and/or colorimetric indicators with the substrate surface allowing their loading to zone borders, thus resulting in the formation of a color gradient. In addition, the found LOD is similar to the value obtained using microfluidic cloth-based analytical devices (µCADs) 38 and slightly higher than the LOD's achieved in representative articles on microfluidic paper-based analytical devices 34,36,[39][40][41][42] and µCADs coupled with electrochemiluminescence and colorimetric detectors. 43,44 The precision of the colorimetric measurements was investigated aiming the intra and inter-microplate comparisons.…”

Biosensors and bioelectronics on smartphone for portable biochemical detection

“…Moreover, utilizing the sample flowing devices, multiplexed monitoring for immune assays can also be developed by lateral flow immunoassay (LFIA) based on smartphone (Lee et al, 2013;Yetisen et al, 2014;Yu et al, 2015;Zangheri et al, 2015). Besides immune assays, smartphone has also been used to capture chemiluminescence linked to redox reactions (Oncescu et al, 2013;Chun et al, 2014;Oncescu et al, 2014;Bueno et al, 2015). Chun et al proposed a paper-based biosensing system to link enzymatic reactions and generation of chromogenic compounds for glucose sensing (Chun et al, 2014).…”

“…Besides immune assays, smartphone has also been used to capture chemiluminescence linked to redox reactions (Oncescu et al, 2013;Chun et al, 2014;Oncescu et al, 2014;Bueno et al, 2015). Chun et al proposed a paper-based biosensing system to link enzymatic reactions and generation of chromogenic compounds for glucose sensing (Chun et al, 2014).…”

Recent advances in lab-on-a-chip for biosensing applications

“…Personal intelligent devices, such as smartphone cameras, can also be used to enhance portability and simplicity. Chun et al (2014) presented a paper-based glucose biosensing system utilizing a smartphone as a signal reader for the colorimetric assay. utilized a smartphone to control elastomeric on-chip valves.…”