Quantum Dots for Pharmaceutical and Biomedical Analysis

Enhanced Peroxidase-Like Activity of MoS2 Quantum Dots Functionalized g-C3N4 Nanosheets towards Colorimetric Detection of H2O2

Nanomaterials ◽

10.3390/nano8120976 ◽

2018 ◽

Vol 8 (12) ◽

pp. 976 ◽

Cited By ~ 8

Author(s):

Peng Ju ◽

Yunhong He ◽

Min Wang ◽

Xiuxun Han ◽

Fenghua Jiang ◽

...

Keyword(s):

Quantum Dots ◽

Catalytic Mechanism ◽

Close Contact ◽

Colorimetric Detection ◽

Active Species ◽

Biomedical Analysis ◽

Exchange Method ◽

Visual Assay ◽

Loading Amount

MoS2 quantum dots (QDs) functionalized g-C3N4 nanosheets (MoS2@CNNS) were prepared through a protonation-assisted ion exchange method, which were developed as a highly efficient biomimetic catalyst. Structural analysis revealed that uniformly-dispersed MoS2 QDs with controllable size and different loading amount grew in-situ on the surface of CNNS, forming close-contact MoS2@CNNS nanostructures and exhibiting distinct surface properties. Compared to MoS2 QDs and CNNS, the MoS2@CNNS nanocomposites exhibited a more than four times stronger peroxidase-like catalytic activity, which could catalyze the oxidation of 3,3’,5,5’-tetramethylbenzidine (TMB) in the presence of H2O2 to generate a blue oxide. Among the MoS2@CNNS nanocomposites, MoS2@CNNS(30) was verified to present the best intrinsic peroxidase-like performance, which could be attributed to the more negative potential and larger specific surface area. A simple, rapid and ultrasensitive system for colorimetric detection of H2O2 was thus successfully established based on MoS2@CNNS, displaying nice selectivity, reusability, and stability. The detection limit of H2O2 could reach as low as 0.02 μM. Furthermore, the kinetic and active species trapping experiments indicated the peroxidase-like catalytic mechanism of MoS2@CNNS. This work develops a novel, rapid, and ultrasensitive approach for visual assay of H2O2, which has a potential application prospect on clinical diagnosis and biomedical analysis.

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Role of quantum dots in pharmaceutical and biomedical analysis, and its application in drug delivery

TrAC Trends in Analytical Chemistry ◽

10.1016/j.trac.2020.116013 ◽

2020 ◽

Vol 131 ◽

pp. 116013 ◽

Cited By ~ 2

Author(s):

Ulya Badıllı ◽

Fariba Mollarasouli ◽

Nurgul K. Bakirhan ◽

Yalcin Ozkan ◽

Sibel A. Ozkan

Keyword(s):

Drug Delivery ◽

Quantum Dots ◽

Biomedical Analysis

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Gold Island-Enhanced Multiplex Quantum Dots Fluorescent System for Biomedical Analysis of Circulating Tumor Nucleic Acids

10.21203/rs.3.rs-500738/v1 ◽

2021 ◽

Author(s):

Jingyan Lin ◽

Yunxia Wu ◽

Ronghua Yang ◽

Jingru Wang ◽

Wenjie Wu ◽

...

Keyword(s):

Quantum Dots ◽

Nucleic Acids ◽

Point Mutations ◽

High Sensitivity ◽

Clinical Samples ◽

Multiplex Detection ◽

Biomedical Analysis ◽

High Detection Rate ◽

Potential Marker ◽

Highly Sensitive

Abstract Background: Circulating tumor nucleic acids (CTNAs) have been employed as the potential marker for tumor diagnosis and management, which are highly related to the tumorigenesis, progression and metastasis processes. Therefore, it is of significance to develop a highly-sensitive and reliable methods for detection of CTNAs, especially the multiplex point mutation detection of blood-derived CTNAs. Results: Herein, a gold island-enhanced multiplex quantum dots (QDs) fluorescent platform was constructed for highly-sensitive detection of CTNAs in serum. The gold island-enhanced multiplex fluorescent strategy was designed as the highly-efficient signal giving-out mode which could amplify the fluorescence of QDs, realized a homogeneous nano-platform for the enrichment, multiplex detection and point mutations monitoring of CTNAs with the principle of base-stacking. A high sensitivity of 10 amol and desirable specificity were achieved, and the performance index for analysis of clinical CTNAs samples indicated that the gold island-enhanced multiplex QDs fluorescent strategy could realize multiplex point mutations detection of CTNAs in complex blood samples. Conclusions: Hence, this platform achieved high detection rate in clinical samples that suitably met the clinical-requirements for multiplex detection and point mutations monitoring of CTNAs, and thus has the potential to serve as the tumor liquid biopsy strategy based on CTNAs.

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Nanostructure of semiconductor quantum dots in a borosilicate glass matrix by complementary use of HREM and AEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100176770 ◽

1990 ◽

Vol 48 (4) ◽

pp. 728-729

Author(s):

M.J. Kim ◽

L.C. Liu ◽

S.H. Risbud ◽

R.W. Carpenter

Keyword(s):

Quantum Dots ◽

Borosilicate Glass ◽

Glass Matrix ◽

Optical Switching ◽

Response Times ◽

Fast Response ◽

Processing Technique ◽

Internal Stresses ◽

Electron Hole ◽

Spatial Dimensions

When the size of a semiconductor is reduced by an appropriate materials processing technique to a dimension less than about twice the radius of an exciton in the bulk crystal, the band like structure of the semiconductor gives way to discrete molecular orbital electronic states. Clusters of semiconductors in a size regime lower than 2R {where R is the exciton Bohr radius; e.g. 3 nm for CdS and 7.3 nm for CdTe) are called Quantum Dots (QD) because they confine optically excited electron- hole pairs (excitons) in all three spatial dimensions. Structures based on QD are of great interest because of fast response times and non-linearity in optical switching applications.In this paper we report the first HREM analysis of the size and structure of CdTe and CdS QD formed by precipitation from a modified borosilicate glass matrix. The glass melts were quenched by pouring on brass plates, and then annealed to relieve internal stresses. QD precipitate particles were formed during subsequent "striking" heat treatments above the glass crystallization temperature, which was determined by differential thermal analysis.

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