Microwave-Assisted Synthesis of Chromium Oxide Nanoparticles for Fluorescence Biosensing of Mercury Ions and Molecular Logic Computing

Abstract

Cumbersome and inefficient synthesis of chromium-based nanomaterials with unique physicochemical properties and bioactivity limits their wide and practical applications. Simple, fast, and green synthesis of chromium-based nanomaterials will help promote the discovery of their properties and expansion of their application fields. Herein, we proposed rapid, inexpensive, and large-scale methods for the synthesis of chromium oxide nanoparticles (Cr2O3 NPs) by simply microwave-heating Cr3+ ions and citrate for several minutes. The citrate-coated Cr2O3 NPs with a universal fluorescence quenching ability as the sensing platform can combine with biomolecules (DNA) for application in fluorescence biosensing of mercury ions and complex molecular logic computing. The Hg2+ assay had wide linear ranges (0.21–2 and 4.2–50.5 μM), a low detection limit (5.78 nM), and good recovery rates in actual water samples. In addition, the interaction of matter and energy (fluorescence) in the Cr2O3 NPs-based sensing system can be used to perform molecular logic gate operations from simple (YES, NOT, AND, and OR gates) to complex circuits. This research can provide an idea for rapid and large-scale preparation of chromium-based nanomaterials and offer an opportunity for the extensive and in-depth exploration of properties (such as unique optical or enzyme-mimetic) and multipurpose applications (sensing, catalysis, logic computing, and encryption) of chromium-based nanomaterials.

Multimorphological Remoldable Silver Nanomaterials from Multimode and Multianalyte Colorimetric Sensing to Molecular Information Technology

“…Note that the selection of A 512nm , A 518nm , and A 524nm was to increase the output channels to obtain more types of logical operations and provide more storage bits for subsequent information encoding. Because the biological thiols (like GSH) can bind to both M-AgN and Hg 2+ , , when Hg 2+ and GSH were inputted to M-AgN, five different logic gates (OR, YES, IMPLY, NOR, NOT) can be constructed according to the seven signal outputs (Figure B). The M-AgN (corresponding to inputs 0, 0) was blue purple solution and exhibited two strong absorption bands at 552 nm and 404 nm.…”

Development of Two-Dimensional Functional Nanomaterials for Biosensor Applications: Opportunities, Challenges, and Future Prospects

“…Ni(OH) 2 nanoplatelets with thicknesses between 60 and 150 nm were evenly dispersed across the ECF surface, preventing the nanoparticles from clumping together. Optimal results were achieved after 20 min of microwave irradiation at 90 • C. In order to detect Hg 2+ ions via fluorescence biosensing, a simple and efficient microwave method was used to synthesize chromium oxide nanoparticles (Cr 2 O 3 NPs) [89]. In the reaction, a couple of metal ions (Mn 2+ , Cr 3+ , Zn 2+ , Cu 2+ , and Ni 2+ ) and sodium citrate as oxidizing agents were heated using the microwave.…”

Microwave-Assisted Synthesis of Silver Nanoparticles for Multimode Colorimetric Sensing of Multiplex Metal Ions and Molecular Informatization Applications

“…When all reactions reached their equilibrium stages, i.e., the "yellow" solutions, the absorption intensity at 425 nm (A 425 nm ) ≤ 1.75, 2.25, or 1.25; at 600 nm, A 600 nm ≤ 0.5; at 800 nm, A 800 nm ≤ 0.5 or 0.4; the maximum absorption wavelength shift |Δλ A | (taking into account that during the input operation, the maximum absorption wavelength would appear as a blue shift and a red shift, and so |Δλ A | was selected as the output) ≤5 or 10 was defined as "0", otherwise as "1". Since both AgNPs and Hg 2+ can bind to the biothiols (like GSH), 68 when Hg 2+ and GSH were added as two inputs to AgNPs, four different logic gates (OR, NOT, YES, AND) can be constructed according to the five signal responses as outputs (Figures 4B and S4A). The AgNP solution was yellow and showed a single strong absorption band peaked at about 425 nm.…”