Sulfanilic Acid Research Articles

Mobile-phone-based colourimetric analysis for determining nitrite content in water

Environmental contextA widespread pollutant in groundwater, rivers and lakes is nitrite, which is commonly determined batchwise by using colourimetry. The batchwise method, however, requires relatively large and expensive instrumentation, and hence is unsuitable for in-field measurements. This work introduces a simple and portable colourimetric analyser based on a mobile-phone camera for monitoring nitrite concentrations in environmental water samples. AbstractA cost-effective and portable colourimetric analyser installed on a mobile phone was used to measure nitrite in water samples in Chiang Mai City, Thailand. The colourimetric detection was based on the Griess reaction, in which nitrite ion reacts with sulfanilic acid under acidic conditions to produce a diazonium salt that further reacts with N-(1-naphthyl)-ethylenediamine dihydrochloride to form a red–violet azo dye. Under controlled conditions using a light-tight box with LED flash lights, images of the red–violet solution were captured using a built-in camera and further analysed by a program, Panalysis, on the mobile phone. The calibration graph was created by measuring the red colour intensity of a series of standard nitrite solutions from 0.09–1.8 mg N L−1. The calibration equation was then automatically stored for nitrite analysis. The results demonstrated good performance of the mobile phone analyser as an analytical instrument. The accuracy (RE <4%) and precision (RSD ≤ 1%, intra- and inter-day) were also obtained with a detection limit of 0.03 mg N L−1 and a sample throughput of 40 samples per hour. Our results establish this simple, inexpensive and portable device as a reliable in-field monitor of nitrite in environmental waters.

Development of a kinetic spectrophotometric method for insecticide diflubenzuron determination in water and baby food samples

A kinetic spectrophotometric method for determining residues of insecticide diflubenzuron 1(4-chlorphenyl)-3-(2,6-diflubenzoyl)urea (DFB) has been developed and validated. Kinetic method was based on the inhibitory effect of DFB on the oxidation reaction of sulfanilic acid (SA) by hydrogen peroxide in the presence of Co2+ ions in a phosphate buffer, which was monitored at 370 nm. DFB can be measured in the concentration interval 0.102 ? 3.40 ?g mL-1 and 3.40 ? 23.80 ?g mL-1. The detection and quantification limits of the method were calculated according to the 3? criteria and found to be 0.077 ?g mL-1 and 0.254 ?g Ml-1, respectively. The relative standard deviations for five replicate determinations of 0.102, 1.70 and 3.40 ?g mL-1 DFB were 2.08, 1.22 and 1.21 %, respectively, for the first concentration interval, and the recovery percentage values were from 94.12 to 97.35 %. HPLC method was used as a parallel method to verify results of the kinetic method. The kinetic method was successfully applied to determine diflubenzuron concentrations in spiked water and baby food samples after solid phase extraction of the samples. The F and t values at 95% confidence level are lower than the theoretical ones, confirming agreement of the developed and the HPLC method.

The ephemeral dihydrate of sulfanilic acid

Evaporation of an aqueous solution of sulfanilic acid (systematic name: 4-aminobenzene-1-sulfonic acid) at 273 K affords a crystalline dihydrate, C6H7NO3S·2H2O. The organic molecule exists as a zwitterion; two zwitterions are aligned in an antiparallel fashion about a crystallographic centre of inversion. They interact directly via two N-H...O hydrogen bonds between the ammonium group of one zwitterion and the sulfonate group of its symmetry-related counterpart, and their aromatic rings are π-stacked, with an interplanar distance of 3.533 (3) Å. One of the cocrystallized water molecules connects the resulting pairs into layers and the second crosslinks the layers into a three-dimensional network. All H atoms connected to N or O atoms find acceptors in suitable geometries. In the resulting crystal, polar and hydrogen-bond-dominated slabs alternate with stacks of organic arene rings. Although the new dihydrate shows efficient space filling, with a packing coefficient of 75.7%, it is unstable and undergoes fast desolvation at room temperature. In this process, the orthorhombic ansolvate forms as a pure phase.

Evaluation of a sulfanilic acid based surfactant in crude oil demulsification: an experimental study

In this study, 2-Amino-5-Dodecyl Benzene Sulfonic Acid (ADBSA) surfactant has been prepared and tested as crude oil emulsions demulsifier. Electrical conductivity method was used to obtain the critical micelle concentration of surfactant. A critical micelle concentration value of 0.225 wt.%. Bottle testing measurements were conducted to investigate the effect of several parameters including temperature, water content, salinity, demulsifier dosage and type of crude oil (composition) on the demulsification efficiency in presence of new synthetic demulsifier. A reduction of emulsion stability was observed with increasing water content or demulsifier dosage decrease. A water separation index of 98% was recorded at 60 °C.

Elaboration of a chemical sensor based on polyaniline and sulfanilic acid diazonium salt for highly sensitive detection nitrite ions in acidified aqueous media

The work describes the use of sulfonic acid-functionalized GCE as a scaffold to build a highly sensitive PANI-based sensor for nitrite ions in aqueous medium.

Dual mode detection of amifostine based on gold nanoparticles and sulfanilic acid functionalized graphene quantum dots

Visual and fluorescence detection of amifostine based on the inner filter effect of gold nanoparticles on sulfanilic acid functionalized graphene quantum dots.

Sulfonated graphene oxide-catalyzed N-acetylation of amines with acetonitrile under sonication

Abstract Sulfonated reduced graphene oxide (rGO-SO3H, SRGO) was synthesized by introducing aryl diazonium salt of sulfanilic acid radicals onto chemically modified reduced graphene oxide (rGO) under sonication. SRGO catalyst was characterized by X-ray diffraction (XRD), Raman spectroscopy, solid state 13C MAS NMR (13C SSNMR), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), transmission electron spectroscopy (TEM), and X-ray photoelectron spectroscopy (XPS). SRGO was efficiently used as a reusable, metal-free, solid acid catalyst for the direct N-acetylation of amines with acetonitrile under sonication into the corresponding amides. Thus, the method could also serve as a novel convenient alternative for the other acetylation reactions under sonication to avoid using toxic substances such as acetic anhydride, acetyl chloride, and acetic acid.

Combined strategy for removal of Reactive Black 5 by biomass sorption on Macrocystis pyrifera and zerovalent iron nanoparticles

Reactive Black 5, RB5, has been used as a model azo dye to evaluate the removal efficiency of sorption on Macrocystis pyrifera biomass (Mpyr) and commercial zerovalent iron nanoparticles (nZVI) in individual and combined treatments. The best conditions for the treatment with the isolated materials were first determined, and then, in series and combined treatments were performed under these conditions, achieving removal efficiencies higher than 80% of the initial dye concentration. Strengths and weaknesses of all removal strategies (individual, in series and combined) are analyzed regarding the application on real effluents. Mpyr efficiently adsorbed RB5, but also increased the total organic content by partial dissolution of components of the algal biomass. Removal experiments with commercial nZVI were also efficient but liberated Fe to the solution, and sulfanilic acid was observed after the treatment as a product of RB5 degradation. In contrast, after the Mpyr treatment, no sulfanilic acid was detected, suggesting that sulfanilic acid is efficiently adsorbed by the biomass. The best condition was the integrated use of Mpyr and nZVI, with a remarkable removal efficiency (69–80%) obtained after only 1 h of treatment. Finally, nZVI were successfully immobilized in Mpyr, and the hybrid material was used to remove RB5 in continuous flow experiments at pH 3, obtaining a removal capacity of 39.9 mg RB5 g−1 after a total processed volume of 630 mL of [RB5]0 = 100 mg L−1.

Sulfanilic acid-modified chitosan mini-spheres and their application for lysozyme purification from egg white.

A cation exchange matrix with zwitterionic and multimodal properties was synthesized by a simple reaction sequence coupling sulfanilic acid to a chitosan based support. The novel chromatographic matrix was physico-chemically characterized by ss-NMR and ζ potential, and its chromatographic performance was evaluated for lysozyme purification from diluted egg white. The maximum adsorption capacity, calculated according to Langmuir adsorption isotherm, was 50.07±1.47mgg-1 while the dissociation constant was 0.074±0.012mgmL-1 . The process for lysozyme purification from egg white was optimized, with 81.9% yield and a purity degree of 86.5%, according to RP-HPLC analysis. This work shows novel possible applications of chitosan based materials. The simple synthesis reactions combined with the simple mode of use of the chitosan matrix represents a novel method to purify proteins from raw starting materials. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 34:387-396, 2018.

Microwave synthesis of sulfanilic acid

AbstractSulfanilic acid represents an important substance, which is frequently utilized in the industry of azo dyes as well as in drug development of antimicrobials (e.g. of sulfonamides). Students can also meet with such type of compounds in chemistry labs, for example, when they estimate pH by methyl orange indicator or prepare Orange II for textile colouring. Both of these dyes are products of azo coupling of sulfanilic acid as diazonium salt withN,N-dimethylaniline or 2-naphthol, respectively. In the article, we focus on the synthesis of sulfanilic acid as a well-known experiment in the organic chemistry education. The synthesis was modified as the solvent free and microwave assisted experiment under semimicroscale conditions. That experiment is very convenient for the organic chemistry courses in the university or the high school teaching.

Synthesis of 2,5-diaryl-1,3-oxazoles containing a carbamate group

Acetophenones containing a methoxycarbonylamino group in position 2, 3, or 4 of the aromatic ring reacted with phenylglycine in the presence of 2 equiv of iodine and 0.5 equiv of sulfanilic acid in DMSO at 100°C for 6 h to give methyl [2(3,4)-(2-phenyl-1,3-oxazol-5-yl)phenyl]carbamates. The reaction was presumed to involve intermediate formation of methyl [(iodoacetyl)phenyl]carbamate. This was confirmed by the isolation of methyl [2-(iodoacetyl)phenyl]carbamate in the reaction of methyl (2-acetylphenyl)carbamate with iodine in glacial acetic acid and its subsequent transformation to methyl [2-(2-phenyl-1,3-oxazol-5-yl)-phenyl]carbamate.

DECOLOURISATION OF REACTIVE BLACK 5 BY KLEBSIELLA PNEUMONIAE ISOLATED FROM ANTARCTICA SEAWATER

The discharge of highly coloured azo dyes effluent has caused serious environmental damages. In this study, bacteria isolated from Antarctica seawater were screened for their ability to decolourise azo dye Reactive Black 5 (RB5). The selected bacterium was further investigated to study its ability to decolourise RB5. The best bacteria from Antarctica seawater that had the ability to decolourise RB5 was identified using 16S rDNA sequence analysis and revealed that the bacteria 15C shared 99% homology to Klebsiella pneumoniae. Selection of the most effective bacteria was followed by its acclimatisation to decolourise higher concentrations of RB5 by growing it in successively higher concentrations of RB5. Following that, optimization of RB5 decolourisation by the selected bacteria was performed using one factor at time (OFAT) including concentration of dye, pH and temperature. The results obtained indicated the optimal condition for decolourisation of RB5 using this bacterium was at pH 10 and 37°C in 70 mg/L RB5 with 98% decolourisation within 24 h under facultative anaerobic treatment. Besides that, 70% of COD removal was achieved after 96 h of sequential anaerobic and aerobic treatment of RB5. In addition, FTIR and HPLC were used to analyze the metabolite of RB5 decolourisation. Products of RB5 decolourisation was confirmed by the presence of sulphanilic acid in HPLC analyses and the changes observed in the functional groups of the FTIR spectrum suggesting the possibility of RB5 degradation. Ammonia test and carbon dioxide test showed higher concentration of ammonia and carbon dioxide that indicates the mineralisation of product after treatment.

Mechanism studies on methyl orange dye degradation by perovskite-type LaNiO3-δ under dark ambient conditions

Perovskite materials have attracted much attention in heterogeneous catalysis. Here, we report a perovskite type material LaNiO3-δ (LNO) for degradation of methyl orange (MO) azo dye in aqueous solutions under dark ambient conditions (room temperature, atmospheric pressure) without additional lights or chemical stimulants. The high degradation percentage of 5ppm MO with 1.5g/L LNO was 94.3% after 4h with a stirring speed of 500rpm. Reactions under nitrogen, oxygen and carbon dioxide conditions were performed with efficiencies of 19.6%, 7.1%, and 96.8% respectively after 6h to understand the mechanism. MO was shown to degrade under dark ambient condition via main intermediates, sulfanilic acid anion and N,N-dimethyl-p-phenylenediamine (DPD), by electrospray ionization mass spectrometry (ESI/MS) and high performance liquid chromatography (HPLC). Degradation of MO under such a mild condition is due to two synergic effects proposed by means of XRD, FTIR, TGA, SEM, and XPS. Nickel is oxidized during MO degradation; lanthanum carbonate (La-analog calkinsite) is formed on the LNO surface due to the aqueous solution environment and speeds up azo bond cleavage. This work unravels the mechanism behind MO degradation by LNO under dark ambient conditions for the first time. It is a fundamental information on perovskite for dye degradation, especially for lanthanum series of perovskite. Excellent perovskite materials should be tailorable for water remediation applications considering the large variety of perovskites in terms of constituents and composition.

Starvation- and xenobiotic-related transcriptomic responses of the sulfanilic acid-degrading bacterium, Novosphingobium resinovorum SA1.

Novosphingobium resinovorum SA1 was the first single isolate capable of degrading sulfanilic acid, a widely used representative of sulfonated aromatic compounds. The genome of the strain was recently sequenced, and here, we present whole-cell transcriptome analyses of cells exposed to sulfanilic acid as compared to cells grown on glucose. The comparison of the transcript profiles suggested that the primary impact of sulfanilic acid on the cell transcriptome was a starvation-like effect. The genes of the peripheral, central, and common pathways of sulfanilic acid biodegradation had distinct transcript profiles. The peripheral genes located on a plasmid had very high basal expressions which were hardly upregulated by sulfanilic acid. The genomic context and the codon usage preference of these genes suggested that they were acquired by horizontal gene transfer. The genes of the central pathways were remarkably inducible by sulfanilic acid indicating the presence of a substrate-specific regulatory system in the cells. Surprisingly, the genes of the common part of the metabolic pathway had low and sulfanilic acid-independent transcript levels. The approach applied resulted in the identification of the genes of proteins involved in auxiliary processes such as electron transfer, substrate and iron transports, sulfite oxidases, and sulfite transporters. The whole transcriptome analysis revealed that the cells exposed to xenobiotics had multiple responses including general starvation-like, substrate-specific, and substrate-related effects. From the results, we propose that the genes of the peripheral, central, and common parts of the pathway have been evolved independently.

A turn-on fluorescent probe for sensitive detection of sulfide anions and ascorbic acid by using sulfanilic acid and glutathione functionalized graphene quantum dots

The rational surface functionalization of graphene quantum dots (GQDs) has attracted much attention to extend their application in fabricating bio/chemical sensing platform. In this paper, a GQDs-based copper ions (Cu2+) modulated dual-functional fluorescent probe was developed. The attachment of sulfanilic acid and glutathione onto GQDs through amide linkage to obtained the functionalized graphene quantum dots (termed as SSGQDs). The SSGQDs exhibit dramatically enhanced green fluorescence compared with GQDs. And the fluorescence of SSGQDs was found to be effectively quenched by Cu2+ via aggregation kinetics with the formation of SSGQDs-Cu(II) complex. Sulfide anions (S2−) exhibits a good capacity to remove Cu2+ from SSGQDs and dissociated SSGQDs-Cu(II) complex, as a result the fluorescence of SSGQDs was turned on again. Moreover, the introduction of ascorbic acid (AA) could also induce the fluorescence recovery, because it could reduce Cu2+ into Cu+ and result in the destruction of the SSGQDs-Cu(II) complex. This method can be used for the selective analysis of S2− and AA down to 12.6nM and 20.3nM, respectively. Furthermore, the applications of this probe for S2− and AA determination in lake water samples and beverage sample have been demonstrated with satisfactory results.

Sulfanilamide in solution and liposome vesicles; in vitro release and UV-stability studies

The main goal of this study was to develop a liposome formulation with sulfanilamide and to investigate the liposomes impact on its release and stability to the UV-A/UV-B and UV-C irradiation. Liposome dispersions with incorporated sulfanilamide were prepared by thin-film hydration method and liposomes role to the sulfanilamide release was investigated by using a dialysis method. Comparatively, sulfanilamide in phosphate buffer solution was subject to release study as well to the UV irradiation providing for the possibilities of kinetics analysis. In vitro drug release study demonstrated that 20% of sulfanilamide was released from liposomes within 1h that is approximately twice as slower as in the case of dissolved sulfanilamide in phosphate buffer solution. The kinetic release process can be described by Korsmeyer–Peppas model and according to the value of diffusion release exponent it can be concluded that drug release mechanism is based on the phenomenon of diffusion. The sulfanilamide degradation in phosphate buffer solution and liposomes is related to the formation of UV-induced degradation products that are identified by UHPLC/MS analysis as: sulfanilic acid, aniline and benzidine. The UV-induced sulfanilamide degradation in the phosphate buffer solution and liposome vesicles fits the first- order kinetic model. The degradation rate constants are dependent on the involved UV photons energy input as well as sulfanilamide microenvironment. Liposome microenvironment provides better irradiation sulfanilamide stability. The obtained results suggest that liposomes might be promising carriers for delayed sulfanilamide delivery and may serve asa basis for further research.

Development and standardization of test systems based on filter paper and modified with vanillin reagent

Reagents and analytical tools for rapid analysis should be standardized and lead to the requirements of the State Pharmacopoeia of Ukraine. Newsprint paper is used as the main analytical tool for rapid analysis of substances with primary aromatic amino group, but it can’t be standardized. The development of test systems based on filter paper and modified with pharmacopeia reagents can be the problem solution. Aim. The aim of the work is development and implementation of test-kits based on filter paper for rapid analysis of compounded preparations that contain primary aromatic amino group in conditions of pharmacies. Methods. Methods of physical immobilization; determination of physical stability of test kits; economic and statistical methods (cost calculation); validation of analytical methods; statistical methods of data processing chemical experiment. Results. Filter paper and pharmacopeia solution of vanillin were used to develop test systems; the possibility of using the test system in practice was investigated with the application of rapid analysis of sulfacetamide and sulfathiazole sodium. The possibility of using of the test system for rapid analysis of 5% aqueous solutions of derivatives of sulfanilic acid amides has been proved; the following detection limits and unreliability intervals for the rapid analysis method using test systems were established: 5.0-9.0 mg/ml for sodium sulfacetamide and 5.3-9.6 mg/ml for sodium sulfathiazole. The test system is stable during 5 months of storage. Manufacturing cost of 1 test system is 0.34 and 0.16 UAH for the first and the next batches, respectively. Conclusions. The proposed test system is stable and accessible for usage in pharmacy as an analytical tool for rapid analysis of derivatives of sulfanilic acid amides

Fabrication of conducting polymer/noble metal nanocomposite modified electrodes for glucose, ascorbic acid and tyrosine detection and its application to identify the marked ages of rice wines

In previous studies, conductive polymers (CPs)/noble metal nanoparticles (NMNPs) composite materials modified electrodes were always applied to distinguish the trace amounts of specific analytes in complex liquid mixtures. In this paper, polymer sulfanilic acid (PABSA)/AuNPs/glassy carbon electrode (GCE), polymer acid chrome blue K (PACBK)/AuNPs/GCE and polymer aspartic acid (PASP)/PtNPs/GCE were fabricated for the identification of the wine age of rice wines with pattern recognitions. The sensitivity of those modified electrodes was exhibited by cyclic voltammetry, and the parameters of electrochemical behaviors was optimized and confirmed gradually. The original responses were recorded by chronoamperometry with multi-frequency rectangle pulse voltammetry and multi-frequency staircase pulse voltammetry, and the feature data correlated with the wine age were extracted from original responses by ‘area method’. Based on the feature data, principal component analysis (PCA, unsupervised method), locality preserving projections (LPP, semi-supervised method) and differential financial analysis (DFA, supervised method) were applied for the classification of rice wine samples with different marked age, and DFA exhibited the most clear result; least squares support vector machines (LSSVM) and library for support vector machines (LIBSVM) were applied for the prediction of the wine ages, and LIBSVM worked better than LSSVM, the correlations based on the training and testing dataset were R2=0.9999 and R2=0.9998, respectively. In conclusion, the CPs/NMNPs/GCEs with pattern recognitions were powerful tools to identify the marked ages of rice wines.

Preparation and characterization of amphiphilic copolymer PVDF-g-PMABS and its application in improving hydrophilicity and protein fouling resistance of PVDF membrane

A facile strategy to improve the hydrophilicity and the antifouling properties of poly(vinylidene fluoride) (PVDF) membranes, a functional monomer of 4-methacrylamidobenzenesulfonic acid (MABS), was designed and synthesized through the amidation reaction between 2-methylacryloyl chloride and sulfanilic acid. Utilizing PVDF and the obtained MABS as reaction monomers, a novel amphiphilic copolymer was firstly prepared by radical polymerization method. The resulting PVDF-g-PMABS was used as a hydrophilic additive in the fabrication of PVDF porous membranes via immersion precipitation process. The surface chemical compositions and structure morphologies of as-prepared blend membranes (PVDF-g-PMABS/PVDF) were characterized by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM), respectively. Contact angle measurement and cross-flow permeation test were employed to evaluate the hydrophilicity and antifouling properties of the membranes. It was found that the blend membrane with 4wt.% PVDF-g-PMABS exhibited a noticeable pure water flux (136.34Lm−2h−1) and a remarkable flux recovery ratio (FRR) of 98.60% in comparison with the pristine PVDF membrane (63.37Lm−2h−1 and 38.67%, respectively). The enhanced performance was attributed to the synergetic effects of the strong hydrogen bonding force and the electrostatic repulsion of sulfonic groups against the protein foulants.

Surface modification of reduced graphene oxide through successive ionic layer adsorption and reaction method for redox dominant supercapacitor electrodes

Non-covalent surface modification technique, where the pre-reduction of graphene oxide (GO) was carried out to recover the π-π conjugation, was performed through a successive ionic layer adsorption and reaction (SILAR) method for preparing redox dominant supercapacitor electrodes. The π-π conjugation of reduced graphene oxide (RGO) facilitated non-covalent interaction with sulfanilic acid azo-chromotrop (SA) to develop electrolyte accessible layer-by-layer (LL) assembly of RGO and SA (LSARGO). In comparison, RGO was modified with SA through continuous stirring of SA and GO, followed by the post reduction technique and designated as NSARGO. The LSARGO revealed higher surface area, electrical conductivity and electrochemical performances than the NSARGO. Sharp redox peaks with well cathodic peak current density vs. square root of the scan rate slope value indicated a redox dominant LSARGO electrode, which was further confirmed by the specific capacitance (SC) values, calculated from the cyclic voltammetry and galvanostatic charge–discharge (GCD) curves in three electrode configuration. The electrochemical impedance spectroscopy study also revealed that the LSARGO provided more redox dominant supercapacitor characteristics as compared to NSARGO. The LSARGO exhibited a SC of ∼1023Fg−1 at scan rate of ∼10mVs−1. The fabricated asymmetric supercapacitor device (ASC) showed an elevated energy and power density of ∼80Whkg−1 and 17,500Wkg−1, respectively. The ASC experienced high GCD cyclic stability of ∼84% after 10,000 cycles.