Quantum Dot Nanomaterials: Preparation, Characterization, Advanced Bio-Imaging and Therapeutic Applications

The bio-imaging technology is one of the most significant modern applications used in several fields, including early diagnosis of many illnesses that are most important diseases facing humanity and other vital uses. The primary advancement in nanotechnology is the creation of innovative fluorescence probes called quantum dots (QDs). The use of molecular tagging in research, in vivo, and in vitro studies is revolutionized by quantum dots. The application of QD indicates conversion in natural imaging and photography has demonstrated extraordinary appropriateness in bio-imaging, the discovery of novel drugs, and delivery of targeted genes, biosensing, photodynamic therapy, and diagnosis. New potential methods of early cancer detection and treatment management are being researched as a result of the special physical and chemical characteristics of QD probes. The bio-imaging technique depends on the fluorescent emission of the used materials, which is paired with living cells that are easy to see it in 3D without any surgical intervention. Therefore, the use of QDs many types that have unique and appropriate properties for use in that application; In terms of fluorescent emission strength, duration and luminosity.This review article displays some methods of preparation for QDs nanomaterials and the devices used in this. In addition, it presentssome of challenges that must be avoided for the possibility of using them in the bio-imaging field; as toxicity, bio-compatibility, and hydrophilization. It's reviewed some of the devices that use QDs in bio-imaging technique, the QDs application in cell analysis-imaging, and QDs application in vivo imaging.

Block Copolymer-Templated Au@CdSe Core-Satellite Nanostructures with Solvent-Dependent Optical Properties

In the present work, we report the fabrication and characterization of well-defined core-satellite nanostructures. These nanostructures comprise block copolymer (BCP) micelles, containing a single gold nanoparticle (AuNP) in the core and multiple photoluminescent cadmium selenide (CdSe) quantum dots (QDs) attached to the micelle's coronal chains. The asymmetric polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) BCP was employed to develop these core-satellite nanostructures in a series of P4VP-selective alcoholic solvents. The BCP micelles were first prepared in 1-propanol and subsequently mixed with AuNPs, followed by gradual addition of CdSe QDs. This method resulted in the development of spherical micelles that contained a PS/Au core and a P4VP/CdSe shell. These core-satellite nanostructures, developed in different alcoholic solvents, were further employed for the time-resolved photoluminescence analysis. It was found that solvent-selective swelling of the core-satellite nanostructures tunes the distance between the QDs and AuNPs and modulates their Förster resonance energy transfer (FRET) behavior. The average lifetime of the donor emission varied from 12.3 to 10.3 nanoseconds (ns) with the change in the P4VP-selective solvent within the core-satellite nanostructures. Furthermore, the distances between the donor and acceptor were also calculated using efficiency measurements and corresponding Förster distances. The resulting core-satellite nanostructures hold promising potential in various fields, such as photonics, optoelectronics, and sensors that utilize the FRET process.

Organic–inorganic nanohybrids based on an AIE luminogen-functional polymer and CdTe/ZnS QDs: morphologies, optical properties, and applications

Dual-emissive organic–inorganic nanohybrid self-assemblies were constructed by binding red-emitting CdTe/ZnS QDs to blue-emitting AIE-active polymeric micelles in water as a fluorescent probe for PA with interesting assembly behaviour.

The high selective chemo-sensors for TNP based on the mono- and di-substituted multifarene[2,2] with different fluorescence quenching mechanism

The chem-sensors, based on the triazole-CH₂-anthracene-functionalized multifarene[2,2] were successfully synthesized, which could efficiently and rapidly detect 2,4,6-trinitrophenol (TNP). The high specificities of the proposed macrocyclic sensors were achieved by selective response for TNP in the existence of other competing phenolic compounds, and the limits of detection in ∼10^-8 mol/L range were produced to confirm the high sensitivities of the chem-sensors, which could be attributed to the mechanism of electron and resonance energy transfer processes in the complexes with the supramolecular interactions. ¹H NMR titration analysis revealed the actual binding position should be the triazole rings of sensors with the hydroxyl group on TNP to offer a hydrogen bonding. The extraordinary sensing properties endued the compounds as sensitive fluorometric chem-sensors for the potential application of TNP detection.

An amphiphilic, heterografted polythiophene copolymer containing biocompatible/biodegradable side chains for use as an (electro)active surface in biomedical applications

Design of an amphiphilic heterografted block copolymer composed of a hydrophobic core backbone and both hydrophilic side chains, able to detect the redox reaction of NADH.