A simple conductometric method for trace level determination of brilliant green in water based on β-cyclodextrin and silver nitrate and determination of their thermodynamic parameters

Cyclodextrin-Based Synthesis and Host-Guest Chemistry of Plasmonic Nanogap Particles with Strong, Quantitative, and Highly Multiplexable Surface-Enhanced Raman Scattering Signals

We developed a synthetic strategy to form cyclodextrin-based intrananogap particles (CIPs) with a well-defined ∼1 nm interior gap in a high yield (∼97%), and were able to incorporate 10 different Raman dyes inside the gap using the cyclodextrin-based host-guest chemistry, leading to strong, reproducible, and highly multiplexable surface-enhanced Raman scattering (SERS) signals. The average SERS enhancement factor (EF) for CIPs was 3.0 × 10⁹ with a very narrow distribution of the EFs that range from 9.5 × 10⁸ to 9.5 × 10⁹ for ∼95% of the measured particles. Remarkably, 10 different Raman dyes can be loaded within the nanogap of CIPs, and 6 different Raman dye-loaded CIPs with little spectral overlaps were distinctly detected for cancer cell imaging applications with a single excitation source. Our synthetic strategy provides new platforms in precisely forming plasmonic nanogap structures with all key features for widespread use of SERS including strong signal intensity, reliability in quantification of signal and multiplexing capability.

Influence of Surface Chemistry on the Electrochemical Performance of Biomass-Derived Carbon Electrodes for its Use as Supercapacitors

Activated carbons prepared by chemical activation from three different types of waste woods were treated with four agents: melamine, ammonium carbamate, nitric acid, and ammonium persulfate, for the introduction of nitrogen and oxygen groups on the surface of materials. The results indicate that the presence of the heteroatoms enhances the capacitance, energy density, and power density of all samples. The samples treated with ammonium persulfate show the maximum of capacitance of 290 F g⁻¹ while for the melamine, ammonium carbamate, and nitric acid treatments, the samples reached the maximum capacitances values of 283, 280, and 455 F g⁻¹ respectively. This remarkable electro-chemical performance, as the high specific capacitances can be due to several reasons: i) The excellent and adequate textural characteristics makes possible a large adsorption interface for electrolyte to form the electrical double layer, leading to a great electrochemical double layer capacitance. ii) The doping with hetero-atoms enhances the surface interaction of these materials with the aqueous electrolyte, increasing the accessibility of electrolyte ions. iii) The hetero-atoms groups can also provide considerable pseudo-capacitance improving the overall capacitance.

A comparison between digital camera and spectrophotometer for sensitive and selective kinetic determination of brilliant green in wastewaters

In this study, a simple and novel kinetic spectrophotometric method has been proposed for the sensitive and highly selective determination of Brilliant Green. The method is based on the interaction of Brilliant Green with Triton X-100 in micellar media at room temperature. As a result of this interaction, the peak wavelength (625 nm) is gradually shifted toward longer wavelength region (634 nm) and more intensive hyper chromic effect has been seen. As well as, variations in the red, blue and green (RGB) components of the images as a function of time were observed. The kinetic interaction of Brilliant Green with Triton X-100 was recorded, using UV-Vis Spectrophotometer-diode array detector and a digital camera. The fixed-time method was used for the construction of a calibration curves. Brilliant Green can be measured in the range of 1.0 to 12.0 mg L^-1 and 1.0 to 10.0 mg L^-1with the detection limit of 0.047 mg L^-1 and 0.037 mg L^-1 using spectrophotometer and digital camera, respectively. The proposed method has been successfully used to determine Brilliant Green in some wastewaters such as textile dye effluent and goldfish farming water in the presence of some triphenylmethan dyes as the interferences.

Synthesis and characterization of ZnO-nanorods loaded onto activated carbon and its application for efficient solid phase extraction and determination of BG from water samples by micro-volume spectrophotometry

The applicability of ZnO-nanorods loaded onto activated carbon (ZnO-NRs-AC) for the dispersive solid phase microextraction (DSPME) of brilliant green (BG) from water samples has been described.