Biocompatible Nanoplatform Based on Mussel Adhesive Chemistry: Effective Assembly, Dual Mode Sensing, and Cellular Imaging Performance

Abstract

able consequences, such as organ failure, cytotoxicity, and brain damage. [6][7][8] Therefore, designing and developing a novel method to detect the concentrations of silver ions will be very significant in environmental and biological fields. To date, numerous analysis ways of monitoring Ag + ions in aqueous media were developed and they could be generalized as follows: such as atomic absorption spectrometry, inductively coupled plasma-mass spectrometry, high-performance liquid chromatography, UV-vis spectrometry, and fluorescence spectrometry. [9][10][11][12][13] Compared to the conventional methods with single signal transduction, the determination of Ag + ions with multiple responses could provide more convincing results. In this contribution, the nanoprobe can specifically detect Ag + ions not only by fluorescence via color changes but also it employs UV-vis absorption spectroscopy to recognize silver ions rapidly. The dual mode sensing is certainly superior to traditional fluorescence and the signals are collected in a more reliable way with accuracy and convenience.It has been well documented that the polydopamine (PDA) and its derivative materials have been extensively discussed in energy, catalytic, environmental, and biomedical fields. [14,15] Under alkaline conditions, the PDA was synthesized by deprotonation and intermolecular Michael addition reaction with the The condensation reaction between methyldopa sesquihydrate and ethylenediamine is reported and the assembled nanoplatform possesses green luminescence at 520 nm with excitation-independent feature. The employment of sodium borohydride during synthesis has stabilized the nanoparticle (NP) size and suppressed uncontrolled autoxidation processes. It is appealing to observe that the fluorescence as well as colorimetric titration demonstrates trace level monitoring of silver ions, and the detection limits are determined to be 68 × 10 −9 m (fluorometric) and 71 × 10 −9 m (colorimetric), respectively. The optical response to Ag + ions is assigned to a static quenching process and the corresponding redox reaction including particle aggregation may cause the "on-off " change. During in vitro studies, two living cell lines (HeLa cells and T-cells) are used and the negligible cytotoxicity of such NP is verified via flow cytometry and 3-(4,5-dimethythiazol-. 2-yl)-2,5-diphenyl tetrazolium bromide assays. More importantly, the visualization of silver recognition in two cells is realized and the availability of polydopamine-type NPs for the purpose of biomedical evaluation can generate considerable interests in future studies.

Preparation of fluorescent organic nanoparticlesviaself-polymerization for tartrazine detection in food samples

“…1a). 33 Using quinine sulphate in 0.1 M H 2 SO 4 (QY = 0.58) as a reference, the QY of PDA NPs was 2.7% and comparable to that in a previous work. 34 Furthermore, more than 90% of the fluorescence intensity was retained as the NaCl concentration increased from 0 to 1.0 M, which promised their feasible application under high ionic strength condition (Fig.…”

“…The stretching vibration mode of CO bond (1650 cm −1 ), bending vibration of N–H bond (1587 cm −1 ) and the stretching vibration mode of C–Nbond (1391 cm −1 ) were also found. 33 Compared with the FT-IR spectra of DA (black line in Fig. 2d), the new peak located at 1048 cm −1 might be correlated with the asymmetric stretching vibration of C–N bond, which confirmed the occurrence of amidation reaction.…”

Exploration of Sulfur-Containing Nanoparticles: Synthesis, Microstructure Analysis, and Sensing Potential

“…In most publications, the signal readout of the fluorescence change could not be operated in a recyclable way. − Herein, the reversibility detection of Ni 2+ could be completed by employing dimethylglyoxime as the restoration reagent to fully recover the green emission (Figure b). After three reversible cycles, the fluorescence intensity would remain stable and no apparent changes were obtained (Figure c).…”

N-Doped Carbon Quantum Dot-MnO2 Nanowire FRET Pairs: Detection of Cholesterol, Glutathione, Acetylcholinesterase, and Chlorpyrifos

“…Currently, most research studies have been focused on the eco-friendly synthesis and optical, electronic, and biochemical applications of N-CQDs. − The doping of nitrogen into carbon frameworks through bottom-up strategies has shown excellent performance in many areas, i.e., biosensing and bioimaging. − The stabilization of the exciton of the CQDs by passivation of surface-active sites through nitrogen doping can effectively improve their emission properties, low toxicity, and high stability. The photoluminescence quantum yield of the N-doped CQDs is much larger than that of undoped CQDs. , Significant attention has been paid to the development of N-CQD-based assays for fluorescence turn off–on sensing and detection of biomolecules, i.e., acid phosphatase, thiol-containing compound, , acetylcholinesterase, uric acid, ascorbic acid, , peroxidase, glucose, alkaline phosphatase, and aflatoxin B 1 .…”