Cr₂O₃–TiO₂-Modified Filter Paper-Based Portable Nanosensors for Optical and Colorimetric Detection of Hydrogen Peroxide

Abstract

In the present approach, a Cr 2 O 3 –TiO 2 -modified, portable, and biomimetic nanosensor was designed to meet the requirement of a robust and colorimetric sensing of hydrogen peroxide. Cr 2 O 3 –TiO 2 nanocomposites prepared via the hydrothermal method were fabricated as a transducer surface on the filter paper using the sol–gel matrix. The color on the filter paper sensor changed from green to blue upon the addition of hydrogen peroxide in the presence of TMB. This change in the color intensity was linear with the concentration of H 2 O 2 . RGB software was used as a color analyzing model to evaluate the optical signals. This paper-based colorimetric platform provided us with an improved analytical figure of merit with a linear range of 0.005–100 μM with 0.003 μM limit of detection. The real sample analysis and excellent anti-interference potential results proved the good analytical performance of the proposed design, providing a more promising tool for colorimetric H 2 O 2 detection. Introducing Cr 2 O 3 –TiO 2 nanocomposite-based paper sensors, being a novel method for optical and colorimetric detection, can pave the way for the development of other sensing devices for the detection of different analytes.

Silk-Hydrogel-Immobilized Gold-Nanocluster-Seeded Catalase Protein as a Pre-Plasmonic Probe for Colorimetric Peroxide Sensing

“…A comparative account of the application of NC-based optical methods for the detection of H 2 O 2 developed through this study with some prominent reports was made (Table S2). − The comparisons indicate that the colorimetric method present here offers an unprecedented wide linear detection range with albeit low sensitivity compared to the other methods. Another stark advantage of the present technique is the label-free detection with no conventional chromogenic agents required for the assay.…”

Quantification of Neuronal Cell-Released Hydrogen Peroxide Using 3D Mesoporous Copper-Enriched Prussian Blue Microcubes Nanozymes: A Colorimetric Approach in Real Time and Anticancer Effect

“…This has led to a search for more efficient CDT agents that can self-provide H 2 O 2 without the need for external energy input. The Fenton-type metal-based multivalent NPs such as Fe 2+ , Ce 3+ , Co 3+ , Cr 2+ , and Cu 2+ have shown excellent catalytic activity in recent studies, making them ideal for CDT nanoagents capable of supplying H 2 O 2 on demand. For instance, copper peroxide (CP) nanodots have been constructed to possess both Fenton-like and CAT-like activity for anticancer purposes .…”

“…Magnetite nanoparticles (Fe 3 O 4 NPs) were among the first reported nanozymes to possess peroxidase-like (POD) activity alike horseradish peroxidase (HRP) . Since then, an array of nanostructures, including monometallic nanomaterials like Au NPs, Ag NPs, Pt NPs, and bimetallic nanoparticles such as Au@Ag nanorods, porous PtCu dendrites, Pt 74 Ag 26 , FePt–Au, metal oxides like MoS 2 , WS 2 , Co 3 O 4 , cerium oxide, as well as mixed metal oxides like Cr 2 O 2 –TiO 2 , ZnCo 2 O 4 , Fe 3 O 4 –Fe 0 /Fe 3 C, metal cluster nanomaterials like mercaptosuccinic acid (MSA)-stabilized Cu nanoclusters, and Fe–N/C single-atom nanozymes, along with metal–organic framework-based nanomaterials, , have found wide applications in colorimetric biosensors for detecting H 2 O 2 . However, these nanostructured materials exhibit certain drawbacks, such as complex synthesis processes and limited biocompatibility.…”

Designing CoS1.035 Nanoparticles Anchored on N-Doped Carbon Dodecahedron as Dual-Enzyme Mimics for the Colorimetric Detection of H2O2 and Glutathione

“…Considering the similar electron structure of Fe, Cu, and Co, we reasonably speculate that the cobaltous sulfides might also hold a great potential to be a mimic enzyme. Although some progress has been made in this field, 25 the exploration of cobaltous sulfides as dual-enzyme mimics and the subsequent application in colorimetric sensing are still in their infancy. Therefore, it is of great significance to develop a bifunctional nanozyme with excellent enzyme-like activity and stability.…”