Zinc-Air Battery-Based Self-Powered Sensor with High Output Power for Ultrasensitive MicroRNA let-7a Detection in Cancer Cells

Abstract

Self-powered sensors do not require a power supply and are easy to miniaturize, which have potential for constructing wearable, portable, and real-time detection devices. However, it is challenging for the detection of low abundant targets due to the low output power density of fuel cells and much interference of complex biological environment. Herein, a new kind of photocatalytic zinc−air battery-based self-powered electrochemical sensor (ZAB-SPES) was constructed for the detection of microRNA let-7a (miRNA let-7a) by combining magnetic nanobeads (MBs) with a metal−organic framework loaded with glucose oxidase (MOFs@GOX). Poly(1,4-di(2-thienyl))benzene (PDTB) was used as the photocathode material, and the proposed ZAB-SPES had a high power density of 22.8 μW/cm 2 , which was 2−3-fold of commonly used photofuel cells. MBs can capture and separate miRNA from complex samples quickly with a high separation efficiency of 99% within 60 s. The competitive reaction of oxygen reduction reaction between PDTB and MOFs@GOX would change the output power density of the ZAB-SPES. Based on the relationship between output power density and target concentration, the ZAB-SPES realized ultrasensitive detection of miRNA let-7a with a detection limit down to 1.38 fM. Furthermore, the successful detection of miRNA let-7a in A549 cancer cells indicated the great prospects of ZAB-SPES in clinical analysis and early diagnosis of cancers.

MicroRNA Biosensors for Early Detection of Hepatocellular Carcinoma

“…In addition to the studies mentioned above, several other near-commercial miRNA biosensors have been developed. Jin et al [62] combined magnetic nanobeads with metalorganic frameworks loaded with glucose oxidase (MOFs@GOX) and constructed a novel The linear detection range of this biosensing platform is 1-200 ng/mL. In the PBS buffer, the LOD for miRNA-155 was calculated to be 17.0 ng/mL and the LOD for miRNA-21 was 9.2 ng/mL through linear fitting.…”

“…In addition to the studies mentioned above, several other near-commercial miRNA biosensors have been developed. Jin et al [62] combined magnetic nanobeads with metalorganic frameworks loaded with glucose oxidase (MOFs@GOX) and constructed a novel self-powered electrochemical sensor based on a photocatalytic zinc-air battery (ZAB-SPES) for the detection of miRNA let-7a. ZAB-SPES has a high-power density of 22.8 µW/cm 2 , which is 2-3 times higher than that of commonly used photofuel cells.…”

Dual-Photoelectrode Fuel Cell Based Self-Powered Sensor for a Picomole Level Pollutant: Using an In Situ Molecularly Imprinted p-Type Organic Photocathode

“…By replacing the traditional platinum plate electrode, the application of p-type photomaterials effectively expands the difference between the Fermi energy levels between the electrodes, thus generating greater self-bias to drive the PFCs . In addition, owing to the detection signal being attributed to the photocathode, it shows great significance to construct a photocathode with excellent environmental friendliness and ideal stability. , Dual-photoelectrode fuel cell (DPFC) based SPSs have been proposed, through integrating n-type and p-type semiconductors as a photoanode and photocathode, respectively. , …”

Specific Adsorption of Magnetic Fe3O4@hydroxyapatite Nanocomposites to a Hybridized Duplex for Immobilization and Label-Free Electrochemical Biosensing of MicroRNA

“…Numerous pathological studies have shown that the abnormal expression of miRNA let-7a in tumor cells and serum is correlated to many cancers, such as hepatocellular carcinoma (HCC), breast cancer, and pancreatic cancer, making miRNA let-7a one of crucial cancer biomarkers. At present, a variety of methods have been developed to detect miRNA let-7a, such as electrochemiluminescence, , fluorescence assays, and electrochemical methods. , Compared to the other methods, the electrochemical biosensing technology has the advantages of simpleness, low cost, and high sensitivity, which are more conducive to the establishment of practical analytical devices.…”

“…At present, a variety of methods have been developed to detect miRNA let-7a, such as electrochemiluminescence, 7,8 fluorescence assays, 9 and electrochemical methods. 10,11 Compared to the other methods, the electrochemical biosensing technology has the advantages of simpleness, low cost, and high sensitivity, which are more conducive to the establishment of practical analytical devices.…”