An Equipment-Free, Paper-Based Electrochemical Sensor for Visual Monitoring of Glucose Levels in Urine

Abstract

A novel electrochemical glucose sensor was created for a simple but semiquantitative visual screening of specific glucose concentrations in urine. This noninvasive glucose biosensor integrated a disposable, paper-based sensing strip and a simple amplifier circuit with a visual readout. The paper strip consisted of five enzyme-activated electrodes. Each electrode was connected to a specific indicator circuit that triggered a light-emitting diode (LED) when a predefined glucose concentration was reached. The device features (1) low-cost, disposable, paper-based glucose oxidase (GOx)/poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) sensing electrodes, (2) simple signal amplification, and (3) on-site, rapid, and visual detection. The sensor generated reliable, discrete visual responses to determine five glucose levels (1, 2, 3, 4, and higher than 4 mM) in urine in less than 2 min. This innovative approach will provide a simple but powerful glucose sensing paradigm for use in POC diagnostics.

Ion‐Gated Transistor: An Enabler for Sensing and Computing Integration

“…Through material selection and structure optimization, IGTs can quantitatively convert physicochemical signals into the easily detectable electrical signals, achieving direct sensing to the change in external environment or life entity. [78,79,[79][80][81][82][83][84][85][86][87][88][89][90][91][92] According to the difference of signals, the IGT-based biosensors can be divided into two categories. One category is used for the detection of biophysical signals, such as light, cardiac rhythm, and brain activity, and the other category is used for the detection of biochemical species, such as glucose, cell receptors, enzymes, antibodies, nucleic acids, and so on.…”

“…Glucose [90,101] High <20 s b) Low Detection limit: 0.5 μM OH À /H þ (pH) [91,104] Low %10 s c) Low %59.12 mV pH À1…”

Lab-on-Paper Devices for Diagnosis of Human Diseases Using Urine Samples—A Review

“…Diabetes is a chronic metabolic abnormality characterized by elevated blood sugar levels over a long period of time. When the blood sugar level exceeds 180 mg/dL, glucose appears in the urine, causing a so-called glucose in urine (GLU) disorder [89,90]. GLU is easily detected through simple urine tests and is regarded as a reliable indicator of early diabetes and kidney disease [91].…”

Recent Advances in the Use of Transition-Metal Porphyrin and Phthalocyanine Complexes as Electro-Catalyst Materials on Modified Electrodes for Electroanalytical Sensing Applications

“…The demand for more reliable and exact analytical devices is based on the constant increment of diabetic patients around the world [34]. There are several proposals of innovative and promising wearable devices based on enzymes for detecting glucose in fluids such as sweat [35], saliva [36][37][38], or urine [39][40][41]; however, the use of enzymes is challenging, and several problems are faced during their immobilization on the electrode's surface. Moreover, the electron transference between the enzyme redox center and the electrode surface is slow, and the glucose oxidation requires elevated positive overpotentials.…”