Fluorometric virus detection platform using quantum dots-gold nanocomposites optimizing the linker length variation

autho

Methylene blue-encapsulated liposomal biosensor for electrochemical detection of sphingomyelinase enzyme

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Detection of Sphingomyelinase Enzyme by Methylene Blue Encapsulated Liposome Applying Electrochemical Amplified Process

64th Annual Meeting of the Biophysical-SocietySan Diego, CAautho

Highly Sensitive and Selective Detection of Nanomolar Ferric Ions Using Dopamine Functionalized Graphene Quantum Dots

The good stability, low cytotoxicity, and excellent photoluminescence property of graphene quantum dots (GQDs) make them an emerging class of promising materials in various application fields ranging from sensor to drug delivery. In the present work, the dopamine-functionalized GQDs (DA-GQDs) with stably bright blue fluorescence were successfully synthesized for low level Fe³⁺ ions detection. The as-synthesized GQDs are uniform in size with narrow-distributed particle size of 4.5 ± 0.6 nm and high quantum yield of 10.2%. The amide linkage of GQDs with dopamine, confirmed by using XPS and FTIR spectra, results in the specific interaction between Fe³⁺ and catechol moiety of dopamine at the interfaces for highly sensitive and selective detection of Fe³⁺. A linear range of 20 nM to 2 μM with a detection limit of 7.6 nM is obtained for Fe³⁺ detection by DA-GQDs. The selectivity of DA-GQDs sensing probe is significantly excellent in the presence of other interfering metal ions. In addition, the reaction mechanism for Fe³⁺ detection based on the complexation and oxidation of dopamine has been proposed and validated. Results obtained in this study clearly demonstrate the superiority of surface functionalized GQDs to Fe³⁺ detection, which can pave an avenue for the development of high performance and robust sensing probes for detection of metal ions and other organic metabolites in environmental and biomedical applications

Fluorometric Sensing Platform Based on Localized Surface Plasmon Resonance using Quantum Dots-Gold Nanocomposites Optimizing the Linker Length Variation

64th Annual Meeting of the Biophysical-SocietySan Diego, CAautho

Advancement of dengue virus NS1 protein detection by 3D-nanoassembly complex gold nanoparticles utilizing competitive sandwich aptamer on disposable electrode

autho

Impedimetric biosensor of Norovirus with low variance using simple bioconjugation on conductive polymer-Au nanocomposite

autho

N‑Doped Graphene Quantum Dots-Decorated V₂O₅ Nanosheet for Fluorescence Turn Off–On Detection of Cysteine

The development of a fast-response sensing technique for detection of cysteine can provide an analytical platform for prescreening of disease. Herein, we have developed a fluorescence turn off–on fluorescence sensing platform by combining nitrogen-doped graphene quantum dots (N-GQDs) with V₂O₅ nanosheets for the sensitive and selective detection of cysteine in human serum samples. V₂O₅ nanosheets with 2–4 layers are successfully synthesized via a simple and scalable liquid exfoliation method and then deposited with 2–8 nm of N-GQDs as the fluorescence turn off–on nanoprobe for effective detection of cysteine in human serum samples. The V₂O₅ nanosheets serve as both fluorescence quencher and cysteine recognizer in the sensing platform. The fluorescence intensity of N-GQDs with quantum yield of 0.34 can be quenched after attachment onto V₂O₅ nanosheets. The addition of cysteine triggers the reduction of V₂O₅ to V⁴⁺ as well as the release of N-GQDs within 4 min, resulting in the recovery of fluorescence intensity for the turn off–on detection of cysteine. The sensing platform exhibits a two-stage linear response to cysteine in the concentration range of 0.1–15 and 15–125 μM at pH 6.5, and the limit of detection is 50 nM. The fluorescence response of N-GQD@V₂O₅ exhibits high selectivity toward cysteine over other 22 electrolytes and biomolecules. Moreover, this promising platform is successfully applied in detection of cysteine in human serum samples with excellent recovery of (95 ± 3.8) – (108 ± 2.4)%. These results clearly demonstrate a newly developed redox reaction-based nanosensing platform using N-GQD@V₂O₅ nanocomposites as the sensing probe for cysteine-associated disease monitoring and diagnosis in biomedical applications, which can open an avenue for the development of high performance and robust sensing probes to detect organic metabolites