Smartphone-Based Chemiluminescent Origami µPAD for the Rapid Assessment of Glucose Blood Levels

Abstract

Microfluidic paper analytical devices (µPADs) represent one of the most appealing trends in the development of simple and inexpensive analytical systems for diagnostic applications at the point of care (POC). Herein, we describe a smartphone-based origami µPAD for the quantitative determination of glucose in blood samples based on the glucose oxidase-catalyzed oxidation of glucose leading to hydrogen peroxide, which is then detected by means of the luminol/hexacyanoferrate(III) chemiluminescent (CL) system. By exploiting the foldable µPAD format, a two-step analytical procedure has been implemented. First, the diluted blood sample was added, and hydrogen peroxide was accumulated, then the biosensor was folded, and a transport buffer was added to bring hydrogen peroxide in contact with CL reagents, thus promoting the CL reaction. To enable POC applicability, the reagents required for the assay were preloaded in the µPAD so that no chemicals handling was required, and a 3D-printed portable device was developed for measuring the CL emission using the smartphone’s CMOS camera. The µPAD was stable for 30-day storage at room temperature and the assay, displaying a limit of detection of 10 µmol L−1, proved able to identify both hypoglycemic and hyperglycemic blood samples in less than 20 min.

Engineering Strategies for Advancing Optical Signal Outputs in Smartphone‐Enabled Point‐of‐Care Diagnostics

“…There are other types of optical biosensors that are based on luminescence, including chemiluminescence, [49] thermochemiluminescence, [50] and electrochemiluminescence. [51] The housing design is similar to the aforementioned structures.…”

High sensitivity and automatic chemiluminescence detection of glucose and lactate using a spin-disc paper-based device

“…16 Additionally, the incubation of glucose oxidation was reported to achieve high detection sensitivity. 10,20 For instance, the wax valves were placed between the sample region and the color length reading channel to control the incubation time of glucose. This method effectively reduced the linear detection range (1-80 mg dL −1 ) and reduced the LOD (0.5 mg dL −1 ) for the distance-based quantification of glucose.…”

An Origami Paper-Based Biosensor for Allergen Detection by Chemiluminescence Immunoassay on Magnetic Microbeads

“…In addition to higher versatility, these devices often possess superior analytical performance, since the vertical flow provides higher assay rapidity and sensitivity [ 21 ]. Coupling this format with CL detection also takes advantage of CL’s specific features [ 22 ], such as amenability to miniaturization as well as high sensitivity and specificity of detection, even though only a few examples have been published up to now [ 23 , 24 , 25 , 26 ]. Furthermore, µPAD-based assays enable the immobilization of biospecific recognition molecules (such as enzymes, antigens, antibodies, aptamers, or nucleic acids) on paper.…”