Surface characterization of thiol ligands on CdTe quantum dots: analysis by 1 H NMR and DOSY

Zhang

Drug Testing and Analysis

et al. 2022

Section: Resultsmentioning

confidence: 99%

Structure identification and analysis of the suspected chemical precursor of 2‐fluorodeschloroketamine and its decomposition products

Zhang

Drug Testing and Analysis

et al. 2022

“…Despite these advantages, it is worth mentioning that CDs show some disadvantages in comparison to SQDs that limit their applications, such as difficulties in preparation, purification, and characterization. In addition, they often provide low quantum yields and certain ambiguity in their geometry and structure [16,17].…”

Section: Synthesis and General Properties Of The Cdsmentioning

confidence: 99%

Carbon Dots: An Insight into Their Application in Heavy Metal Sensing

Echeverry-Gonzalez¹,

Kouznetsov²

2020

RPM

The design of nanomaterials for application in diverse fields ranging from photovoltaic to fluorescence sensing is a research area of increasing interest. Recently, Quantum Dots (QDs), which are classified as semiconductor quantum dots (SQDs) and Carbon dots (CDs), have become a hot topic of investigation, owing to their extraordinary tunable fluorescence emission properties that render them excellent candidates for sensing metal ions. The detection of metal ions in aqueous solutions with high sensitivity is very important as these ions have toxicological and environmental impacts. In this short review, we have described the fluorescence emission properties of CDs and their application for the detection of different metal ions, such as Hg2+, Pb2+, Cu2+, Fe3+, Cd2+, and Cr6+.

“…The latter factor is the reason behind the aggregation of NPLs in biological liquids. The improvement of biocompatibility and colloidal stability of semiconductor nanomaterials has been already approached via numerous functionalization techniques, such as exchange or addition of shorter ligand to the nanoparticle surface (mainly thiols 11 ), deposition of polymer coating 12 or encapsulation in amphiphilic polymers, 13 and encapsulation in micelles, 14 oil-core nanocarriers, 15 micro-, and nanoparticles. 16 While the above techniques generally proved effective in the case of semiconductor nanoparticles, to our best knowledge, colloidal semiconductor NPLs have been successfully transported to the water environment only by ligand exchange method.…”

Section: Introductionmentioning

confidence: 99%

Polymeric Nanocarriers with Luminescent Colloidal Nanoplatelets as Hydrophilic and Non-Toxic Two-Photon Bioimaging Agents

Nawrot¹,

Zarȩba²,

Toporkiewicz³

et al. 2021

IJN

Introduction Semiconductor nanoplatelets (NPLs) are promising materials for nonlinear optical microscopy since they feature good two-photon absorption (TPA) properties, narrow photoluminescence spectra and high quantum yields of luminescence. Nevertheless, the use of semiconductor NPLs is inevitably connected with concerns about heavy metal ion toxicity and their intrinsically hydrophobic character. Methods Our contribution focuses on the design and engineering of coloidal bionanomaterial consisting of two-dimensional highly luminescent CdSe semiconductor NPLs loaded into spherical and homogeneous polymeric nanocarriers (NCs) based on poly(ethylene oxide) and poly(propylene oxide) block co-polymer. The biocompatibility and usefulness of the NPLs-loaded polymeric NCs in two-photon induced bioimaging was demonstrated in vitro by cytotoxicity and two-photon microscopic studies using eukaryotic (normal fibroblasts and cancer ovarian) cells. Results The encapsulated NPLs maintain their intensive and spectrally narrow photoluminescence, as well as preserve good TPA properties, while the surrounding polymer shell imparts hydrophilic character and non-toxicity towards eukaryotic cells. Specifically, TPA cross-sections of the colloidal NCs loaded with NPLs show large values reaching up to 2.0 × 10 8 GM, with simultaneously two-photon brightness reaching 2.2 × 10 7 GM at 870 nm. MTT proliferation assay performed on cell lines treated with encapsulated NPLs revealed at least 70% viability of normal human gingival fibroblast (HGF) and cancer ovarian (MDAH-2774) cells, while the results of multiphoton imaging of murine (L-929) fibroblasts suggest that the encapsulated NPLs are capable of labelling the target cells enabling their visualization. Conclusion As a result, we obtained water dispersible and temporally stable hydrophilic NPLs-loaded NCs that offer excellent, both one- and two-photon excited fluorescence preserving optical properties of the raw hydrophobic and colloidal NPLs. The biological responses upon eukaryotic cells indicate that the encapsulation process protects cells from the toxic influence of cadmium simultaneously preserving the unique multiphoton properties of the active cargo which opens a promising perspective for its application in multiphoton cancer bioimaging excited at the “optical transmission window” of biological tissues in near-infrared range.