Wide-Linear Range Cholesterol Detection Using Fe₂O₃ Nanoparticles Decorated ZnO Nanorods Based Electrolyte-Gated Transistor

Abstract

Electrolyte-gated transistor (EGT)-based biosensors are created with nanomaterials to harness the advantages of miniaturization and excellent sensing performance. A cholesterol EGT biosensor based on iron oxide (Fe2O3) nanoparticles decorated ZnO nanorods is proposed here. ZnO nanorods are directly grown on the seeded channel using a hydrothermal method, keeping in mind the stability of nanorods on the channel during biosensor measurements in an electrolyte. Most importantly, ZnO nanorods can be effectively grown and modified with Fe2O3 nanoparticles to enhance stability, surface roughness, and performance. The cholesterol oxidase (ChOx) enzyme is immobilized over Fe2O3 nanoparticles decorated ZnO nanorods for cholesterol detection. With cholesterol addition in buffer solution, the electro-oxidation of cholesterol on enzyme immobilized surface led to increased the biosensor’s current response. The cholesterol EGT biosensor detected cholesterol in wide-linear range (i.e., 0.1 to 60.0 mM) with high sensitivity (37.34 µA/mMcm2) compared to conventional electrochemical sensors. Furthermore, we obtained excellent selectivity, fabrication reproducibility, long-term storage stability, and practical applicability in real serum samples. The demonstrated EGT biosensor can be extended with changing enzymes or nanomaterials or hybrid nanomaterials for specific analyte detection.

“Three-in-one” platform based on Fe-CDs nanozyme for dual-mode/dual-target detection and NIR-assisted bacterial killing

“…The LOD was estimated to be 0.42 mM according to the 3S/N principle, which was consistent with or better than those of other methods in previous reports. 40,64,65 3.6.2. Fluorometric detection of cholesterol.…”

Electrochemical Sensing of Uric Acid with Zinc Oxide Nanorods Decorated with Copper Oxide Nanoseeds

“…and their nanocomposites (i.e., ZnO-CuO, ZnO-Au, ZnO-Fe 2 O 3 , ZnO-polyaniline, ZnO-MWCNTs, etc.) have been utilized for fabrication of electrochemical-based sensors (enzymatic/non-enzymatic) for detection of different biomolecules and for health sciences. − Mainly, zinc oxide (ZnO) nanostructures have been employed in designing improved sensors due to their easy and cost-effective synthesis approach, high surface-to-volume ratio, and being easily modified with other metal/metal oxides. − However, ZnO nanomaterial-based hybrid nanostructures are preferred nanomaterials for the fabrication of different sensing devices with enhanced sensing properties compared to only ZnO nanostructure-based sensors. − For example, recently, Sideeq Bhat et al used hybrid nanostructures of Au-ZnO NRs for the fabrication of an electrochemical-based sensor . They reported enhanced electrochemical properties of Au nanoparticle-modified ZnO nanorods while detecting 5-hydroxymethylcytosine in genomic DNA.…”

“…Ahmad et al used a hybrid nanostructure of ZnO and CuO (ZnO-CuO) for designing a non-enzymatic glucose biosensor, where CuO showed enzyme-like activity and helped to detect glucose . In other reports, Ahmad et al, Ahn et al, and Khan et al used a hybrid nanostructure of ZnO-Fe 2 O 3 for nitrite, potassium, and cholesterol sensing, respectively. − In these reports, ZnO surface modification enhanced the catalytic features by enhancing the surface area. Dhingra et al reported the interfacial interactions of ZnO and polyaniline nanocomposites for optical and ammonia sensing by using hybrid nanostructures of ZnO-polyaniline .…”

Highly Sensitive Zinc Oxide Fiber-Optic Biosensor for the Detection of CD44 Protein

“…Today, ZnO is widely used to detect glucose [ 18 ], cholesterol [ 19 ], uric acid [ 20 ], leptospira [ 21 ], antigens [ 22 ], ascorbic acid [ 23 ], cancer cells [ 24 ], DNA [ 25 ], and various biomarkers [ 26 ]. This semiconductor material is widely used in gas sensors [ 27 ], for targeted delivery of anticancer drugs [ 28 ], and other applications [ 29 ].…”