A new fabricated hetero-atom doped carbon quantum dots as a fluorescent probe for metronidazole determination using garlic and red lentils with microwave assistance.

Biocompatible and highly fluorescent phosphorus, nitrogen and sulfur carbon quantum dots (P,N,S-CQDs) were synthesized using a quick and ecologically friendly process inspired from plant sources. Garlic and red lentils were utilized as natural and inexpensive sources for efficient synthesis of the carbon-based quantum dots using green microwave-irradiation, which provides an ultrafast route for carbonization of the organic biomass and subsequent fabrication of P,N,S-CQDs within only 3 min. The formed P,N,S-CQDs showed excellent blue fluorescence at λem = 412 nm when excited at 325 nm with a quantum yield up to 26.4%. These fluorescent dots were used as a nano-sensor for the determination of the commonly used antibacterial and antiprotozoal drug, metronidazole (MTR). As MTR lacked native fluorescence and prior published techniques had several limitations, the proposed methodology became increasingly relevant. This approach affords sensitive detection with a wide linear range of 0.5-100.0 µM and LOD and LOQ values of 0.14 µM and 0.42 µM, respectively. As well as, it is cost-effective and ecologically benign. The MTT test was used to evaluate the in-vitro cytotoxicity of the fabricated P,N,S-CQDs. The findings supported a minimally cytotoxic impact and good biocompatibility, which provide a future perspective for the applicability of these CQDs in biomedical applications.

Ginseng root extract-mediated synthesis of monodisperse silver nanoparticles as a fluorescent probe for the spectrofluorometric determination of nilvadipine; Evaluation of remarkable anti-bacterial, anti-fungal and in-vitro cytotoxic activities.

Nanoparticles are a boon for humanity because of their improved functionality and unlimited potential applications. Considering this significance, the proposed study introduced a simple, fast and eco-friendly method for synthesis of fluorescent silver nanoparticles (Ag-NPs) using Panax Ginseng root extract as a reducing and capping agent. Synthesis of Ag-NPs was performed in one step within three minutes utilizing microwave irradiation. The resulting Ag-NPs were characterized using various microscopic and spectroscopic techniques such as, Transmission Electron Microscope (TEM), UV/Visible spectroscopy, Fourier Transform Infrared Spectroscopy(FTIR) and Energy Dispersive X-ray analysis (EDX). The prepared Ag-NPs, which act as a fluorescent nano-probe with an emission band at 416 nm after excitation at 331 nm, were used to assay nilvadipine (NLV) spectrofluorimetrically in its pharmaceutical dosage form with good sensitivity and reproducibility. The proposed study is based on the ability of NLV to quantitatively quench the native Ag-NPs fluorescence, forming a ground state complex as a result of static quenching and an inner filter mechanism. The suggested approach displayed a satisfactory linear relationship throughout a concentration range of 5.0 µM - 100.0 µM, with LOD and LOQ values of 1.18 µM and 3.57 µM, respectively. Validation of the suggested approach was examined in accordance with ICH recommendations. In addition, the anti-bacterial and anti-fungal activities of the prepared nanoparticles were investigated, and they demonstrated effective anti-microbial activities and opened a future prospective to combat future antibiotic resistance. Finally, in-vitro cytotoxicity assay of Ag-NPs against normal and cancerous human cell lines was studied using MTT assay. The results proved the potential use of the produced Ag-NPs as an adjunct to anticancer treatment or for drug delivery without significantly harming healthy human cells.

Microwave assisted synthesis of fluorescent hetero atom doped carbon dots for determination of betrixaban with greenness evaluation.

A simple, rapid and eco-friendly method for synthesis of nitrogen and sulfur doped carbon dots (N,S-CDs) is described. The method involved one step carbonization assisted by a green microwave irradiation route using available and cheap sources, as sucrose (source for C) and thiourea (source for N and S). The formed aqueous solution of N,S-CDs showed excellent optical and electronic properties with high compatibility and stability. The particles of the prepared dots were spherical with a narrow range of size from 1.7 to 3.7 nm with a quantum yield of 0.20. These dots act as a fluorescent probe, as they showed an intense blue fluorescence at 413 nm after excitation at 330 nm. The N,S-CDs were utilized for determination of the anticoagulant drug, betrixaban maleate (BTM), based on quenching of their fluorescence upon its gradual addition. The quenching process was found to be through an inner filter effect mechanism. The proposed method showed a good linearity over a concentration range of (1.0-100.0 µM) with LOD and LOQ values of 0.33 µM and 0.99 µM, respectively. All validation parameters met the acceptance criteria according to ICH guidelines. The high specificity and sensitivity of the performed method contributed to further assay of BTM in dosage form and spiked human plasma sample with high percent recoveries and low values of RSD. Interference from co-administered drugs was studied. Finally, the greenness of the proposed method was evaluated adopting a ComplexGapi approach, the excellent green profile has supported its applicability in quality control laboratories.