Isolation and characterization of Pseudomonas otitidis WL-13 and its capacity to decolorize triphenylmethane dyes

Pseudomonas otitidis WL-13, which has a high capacity to decolorize triphenylmethane dyes, was isolated from activated sludge obtained from a wastewater treatment plant of a dyeing industry. This strain exhibited a remarkable color-removal capability when tested against several triphenylmethane dyes under both shaking and static conditions at high concentrations of dyes. More than 95% of Malachite Green and Brilliant Green was removed within 12 h at 500 μmol/L dye concentration under shaking conditions. Crystal Violet lost about 13% of its color under the same conditions tested. The rate of decolorization increased when the M9 medium was supplemented with yeast extract. The optimum pH and temperature for color removal were 7-9 and 35-40℃, respectively. The observed changes in the visible spectra and the inspection of bacterial growth indicated the color-removal by the adsorption of dye to the cells during incubation with strains.

Separation,preconcentration and determination of Pb(Ⅱ) in water samples using microcrystalline triphenylmethane loaded with quinolin-8-olate

This paper described a novel method for the preconcentration of Pb（II） using microcrystalline triphenylmethane loaded with quinolin-8-olate prior to the determination by flame atomic absorption spectrometry. Pb（II） could be enriched by controlling appropriate condition. The preconcentration factor could reach to 200 and the detection limit of Pb（II） was 0.074 μg/L. The recovery was in a range of 93.5-103% with relative standard deviation of 1.0-2.2%. The proposed method had been successfully applied to the determination of trace Pb（U） in various water samples with satisfactory result.

The interaction between furosemide-palladium (Ⅱ) chelate and basic triphenylmethane dyes by resonance Rayleigh scattering spectra and resonance non-linear scattering spectra and their analytical applications

In pH 4.5-7.0 Britton-Robinson buffer solution,furosemide (FUR) reacted with Pd (II) to form a 1:1 anionic chelate.This chelate could further react with such basic triphenylmethane dyes (BTPMD) as ethyl violet (EV),crystal violet (CV),methyl violet (MV),methyl green (MeG) and brilliant green (BG) to form 1:1 ion-association complexes.This not only resulted in the change of absorption spectra,but also led to the significant enhancement of resonance Rayleigh scattering (RRS),second-order scattering (SOS) and frequency doubling scattering (FDS).The maximum RRS wavelengths were located at 324 nm for the EV,CV and MV system,and 340 nm for the BG and MeG system.The maximum SOS wavelengths were located at 550 nm for the EV,CV,BG and MeG system,and 530 nm for the MV system.The maximum scattering peaks of all the systems were at 392 nm for FDS.The enhanced RRS,SOS and FDS intensities were directly proportional to the concentration of FUR.The detection limits for the different dye systems were 0.3-4.9 ng mL-1 for the RRS method,3.2-33.1 ng mL-1 for the SOS method and 9.0-85.7 ng mL-1 for the FDS method.These methods could be used for the determination of trace amounts of FUR.The effects of the formation of ternary ion-association complexes on the spectral characteristics and intensities of absorption,RRS,SOS and FDS have been investigated.The optimum conditions of these reactions,the influencing factors and the analytical properties have been tested.The influences of coexisting substances were tested by RRS method and the results showed that this method exhibited a high sensitivity.Based on the aforementioned research,the highly sensitive,simple and rapid methods for the determination of trace amounts of FUR by resonance light scattering technique have been established,which could be applied to the determination of FUR in tablet,injection,human serum and urine samples.The composition and structure of the ternary ion-association complex and the reaction mechanism were discussed.

Study on Preconcentration of Trace Copper Using Microcrystalline Triphenylmethane Loaded with Malachite Green

The paper describes a novel method for copper preconcentration using microcrystalline triphenylmethane loaded with malachite green prior to the determination by the flame atomic absorption spectrometry （FAAS）. Under the optimum conditions, Cu（Ⅱ） can be totally adsorbed on the surface of microcrystalline triphenylmethane, and completely separated from Pb（Ⅱ）, Cd（Ⅱ）, Co（Ⅱ）, Cr（Ⅲ）, Ni（Ⅱ）, Mn（Ⅱ）, Fe（Ⅲ） and Al（Ⅲ） by controlling acidity. The preconcentration factor of this proposed method is 200. The recovery is in a range of 97.5%-105%. The relative standard deviation （RSD） is not beyond 3.0%. The proposed method has been successfully applied to the determination of trace copper in various water samples with satisfactory results.

Anthraquinone acted as a catalyst for the removal of triphenylmethane dye containing tertiary amino group: Characteristics and mechanism

Herein,we found that anthraquinone(AQ)acted as a catalyst for the rapid and effective removal of triphenylmethane dye containing tertiary amino group(TDAG).Results showed that AQ had an enhanced catalytic reactivity towards the removal of TDAG compared to hydro-quinone,which was further proved and explained using density functional theory(DFT)calculations.AQs could achieve a TDAG removal efficiency and rate of approximately 100%and 0.3583 min^(−1),respectively,within 20 min.Quenching experiments and electron paramagnetic resonance(EPR)tests indicated that the superoxide radical(O_(2)^(•−))generated through the catalytic reduction of an oxygen molecule(O_(2))by AQ contributed to the effective removal of the TDAG.In addition,itwas found that the electrophilic attack of the O_(2)^(•−)radical on the TDAG was the driving force for the dye degradation process.Decreasing the pH led to protonation of the substituted group of AG,which resulted in formation of an electron deficient center in the TDAGmolecule(TDAG-EDC+)through delocalization of the π electron.Therefore,the possibility of the electrophilic attack for the dye by the negative O_(2)^(•-)radical was significantly enhanced.This study revealed that the H+and the O_(2)^(•−)generated by the catalytic reduction of O_(2) have synergistic effects that led to a significant increase in the dye removal rate and efficiency,which were higher than those obtained through persulfate oxidation.