Search

In recent years, nanomaterials have attracted the research intervention of experts in the fields of catalysis, energy, biomedical testing, and biomedicine with their unrivaled optical, chemical, and biological properties. From basic metal and oxide nanoparticles to complex quantum dots and MOFs, the stable preparation of various nanomaterials has always been a struggle for researchers. Microfluidics, as a paradigm of microscale control, is a remarkable platform for online stable synthesis of nanomaterials with efficient mass and heat transfer in microreactors, flexible blending of reactants, and precise control of reaction conditions. We describe the process of microfluidic preparation of nanoparticles in the last 5 years in terms of microfluidic techniques and the methods of microfluidic manipulation of fluids. Then, the ability of microfluidics to prepare different nanomaterials, such as metals, oxides, quantum dots, and biopolymer nanoparticles, is presented. The effective synthesis of some nanomaterials with complex structures and the cases of nanomaterials prepared by microfluidics under extreme conditions (high temperature and pressure), the compatibility of microfluidics as a superior platform for the preparation of nanoparticles is demonstrated. Microfluidics has a potent integration capability to combine nanoparticle synthesis with real-time monitoring and online detection, which significantly improves the quality and production efficiency of nanoparticles, and also provides a high-quality ultra-clean platform for some bioassays., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

A europium nanoparticle-based lateral flow immunoassay for highly sensitive detection of chloramphenicol residue was developed. The detection result could be either qualitatively resolved with naked eye or quantitatively analyzed with the assistance of a digital camera. In the qualitative mode, the limit of detection (LOD) was found to be 0.25 ng/mL. In the quantitative mode, the half-maximal inhibition concentration (IC50) was determined to be 0.45 ng/mL and the LOD can reach an ultralow level of 0.03 ng/mL, which is ~100 times lower than that of the conventional colloidal gold-based lateral flow immunoassay. Potential application of the established method was demonstrated by analyzing representative cow milk samples. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

An ultrasonic method to synthesize gold nanoparticles with uniform size was reported. Effects of ethanol concentration, solution pH, ultrasonic irradiation power, and time on the formation of gold nanoparticles were investigated. The obtained gold nanoparticles were characterized by ultraviolet-visible (UV-vis) absorption spectra and scanning electron microscope (SEM). The method performed in ethanol solution under ultrasonic irradiation is friendly to the environment. Furthermore, a nanogold-labeled probe was used to develop an immunochromatographic method for detection of kanamycin. [ABSTRACT FROM AUTHOR]

Abstract: The synthesis of water-soluble fluorescent carbon dots (C-dots) has received much attention recently. Here, high quality fluorescent C-dots have been synthesized through low-temperature carbonization and simple filtration using watermelon peel, a waste and reproducible raw resource, as a novel carbon resource. This facile approach allows large-scale production of aqueous C-dots dispersions without any post-treatment process. The as-prepared C-dots possess small particle sizes (~2.0nm), strong blue luminescence, acceptable fluorescence lifetime and good stability in a wide range of pH values (pH 2.0–11.0) and at a high salt concentration. Besides, the obtained C-dots have been successfully applied in live cell imaging, indicating these carbon nanoparticles can serve as high-performance optical imaging probes. [Copyright &y& Elsevier]