Journal: Advanced Science
Article Title: Rapid Decentralized Prostate Cancer Risk Stratification by Portable Liquid Biopsy Analysis within a Clinical Biosensor Validation Framework
doi: 10.1002/advs.202512126
Figure Lengend Snippet: AVATAR (Accelerated noninvasive bioanalyte Testing and Reporting), a miniaturized biosensor device for rapid decentralized profiling of clinically accredited RNA biomarkers in patient urine/plasma specimens. (a) The AVATAR device is palm‐sized with eight separate slots for individual electrode insertion and output signal measurement. (b) Each slot is linked to a potentiostat capable of measuring a wide range of current (±7.5 µA). The eight potentiostats were connected to a digital‐to‐analog converter for potential control, an analog‐to‐digital converter for signal digitization, a multiplexer for channel selection, and a microcontroller unit for system operation. An external smartphone with a customized app can communicate with the AVATAR device wirelessly via Bluetooth for operational control and data logging. (c) The AVATAR device is designed to be encased within a 3D‐printed casing for use with up to eight “plug‐and‐play” screen‐printed electrodes simultaneously. This design offers high scalability and flexibility of various array size formats with rapid chronoamperometric readout. (d) Circulating RNA is first extracted from patient liquid biopsy samples. Primer‐functionalized magnetic beads specific for each of the six biomarkers (T2:ERG, PCA3 , SChLAP1 , HOXC6 , DLX1 , KLK2 ) are introduced to initiate isothermal amplification of biomarkers on the bead surfaces. Biotin‐modified uracil bases are randomly incorporated into the amplicons. (e) The magnetic bead‐bound amplicons are labeled with peroxidase enzymes via biotin‐streptavidin bonds and magnetically concentrated on the electrode surface. The electrode is plugged into the AVATAR device to initiate chronoamperometric readout, and the resultant current signal (corresponding to biomarker level) is measured. HRP, horseradish peroxidase; TMB, 3,3′,5,5′‐tetramethylbenzidine; H 2 O 2, hydrogen peroxide.
Article Snippet: The AVATAR device consists of a microcontroller (ATSAMD21G18 ARM Cortex M0 processor, Microchip Technology Inc.) onboard an off‐the‐shelf module (Adafruit Feather M0 Bluefruit LE, Adafruit Industries LLC), a digital‐to‐analog converter (DAC8552, Texas Instruments), an analog‐to‐digital converter (ADC7684, Analog Devices), a multiplexer (ADG708, Analog Devices), and eight potentiostats.
Techniques: Clinical Proteomics, Control, Selection, Magnetic Beads, Amplification, Modification, Labeling, Biomarker Discovery
