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Cadmium sulfide (CdS) quantum dots (QDs) are formed within poly(ethylene oxide)-block-polystyrene-block-poly (acrylic acid) (PEO-b-PS-b-PAA) triblock copolymer aggregates of different architectures. These structures are obtained starting with the same ionically cross-linked primary micelles consisting of a cadmium acrylate core, a PS shell, and a PEO corona. One morphology is a worm-shaped micelle prepared in tetrahydrofuran (THF) in which the CdS QDs are surrounded by the PAA and aligned as a loose necklace in the PS matrix. The PEO serves as a corona around the PS rod. Another structure is a multicore spherical (ca. 50 nm) water soluble PS micelle, surrounded by PEO chains. The CdS particles within these two latter structures are formed by the reaction of cadmium ions present in the acrylate cores with hydrogen sulfide. In a third structure, the CdS QDs are located on the surface of PS micelles. A fourth spherical single-core micelle structure is postulated to exist in dilute THF solutions. The dimensions in all the aggregates can be controlled by the block length.
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http://dx.doi.org/10.1021/ja0505043 | DOI Listing |
Anal Chim Acta
November 2025
The Associated Laboratory for Green Chemistry (LAQV) of the Network of Chemistry and Technology (REQUIMTE) - the Portuguese Research Centre for Sustainable Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, 4050-313, Porto, Portugal. Electronic address:
Background: When using semiconductor quantum dots (QDs) for single-analyte sensing, recognition is commonly achieved through interactions with capping ligands attached to the QDs surface. These ligands form an organic layer that provides stability in solution and assures selectivity by binding the target analyte via surface functional groups. However, a common analytical challenge arises in the subsequent stage of the QD-based sensing scheme.
View Article and Find Full Text PDFAnal Chim Acta
November 2025
Guangxi Key Laboratory of Natural Polymer Chemistry and Physics, Key Laboratory of Nanobiosensor Analysis, College of Chemistry and Materials, Nanning Normal University, Nanning, 530001, PR China. Electronic address:
Background: Hexavalent chromium ions (Cr(VI)), a notorious toxic heavy metal pollutant with proven carcinogenicity, endangers human health and the environment. Meanwhile, l-ascorbic acid (L-AA), a vital biological antioxidant, has abnormal levels closely tied to various diseases. Developing efficient synchronous detection methods for these two key analytes is of great value in clinical and environmental monitoring.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
September 2025
Department of Pharmaceutical Sciences, Philadelphia College of Pharmacy, Saint Joseph's University, Philadelphia, PA 19104, USA. Electronic address:
The clinical demand for safer, more precise, and functionally versatile imaging tools has intensified with the increasing complexity of disease diagnosis and management. Despite major strides in imaging technologies such as MRI, CT, USG, and PET/SPECT, many modalities are grappled by issues including low specificity, high systemic toxicity of contrast agents, and limited ability to provide real-time functional data. Dreaded by these shortcomings, nanotechnology-based approaches such as liposomes, quantum dots (QDs), polymeric nanoparticles (NPs), gold NPs, lipid NPs, and metallic NPs have emerged as promising alternatives.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
September 2025
Institute of Functional Molecules, Shenyang University of Chemical Technology, Shenyang 110142, China.
A new variety of nitrogen-doped carbon dots (NCDs) was produced using a hydrothermal synthesis method, based on propanedioic acid and barbituric acid as the sources of carbon and nitrogen. The NCDs were analyzed by X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), Zeta Potential,X-ray Diffraction(XRD),Thermogravimetry-Derivative Thermogravimetry(TG-DTG),Fourier transform infrared spectroscopy (FTIR) and Fluorescence Lifetime. The characterization results indicate that NCDs possess an average diameter of approximately 2.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
September 2025
Key Laboratory of Eco-chemical Engineering, Ministry of Education, International Science and Technology Cooperation Base of Eco-chemical Engineering and Green Manufacturing, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao, 266042, P. R. China.
Facing the massive energy consumption of over 200 TWh y of chlor-alkali industry, developing high-activity and durable non-precious CER (chlorine evolution reaction) catalysts is urgently needed to address the high overpotentials and suppress the dissolution high-valance metal species. Herein, a carbon quantum dots functionalized trimetallic Fe/Co/Ni spinel oxide nanotube architecture (FCNO@CQDs) is constructed, featuring t-to-π* π-backbonding for dramatically enhanced CER activity and stability. The reverse electron flow from Co d-obritals to the vacant CQDs' π* orbitals can upshift the d-band center for enhanced intermediate adsorption, while stabilizing high-valent Co centers via increased bond order.
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