Important Analytical Techniques Research Articles

Tripartite synergy: Photodegradation of congo red and bromothymol blue with concurrent bacterial photoinhibition using ZnCe/Bi2Mn2O6/rGO nanocomposites

The present research studies show the multidimensional characteristics of ZnCe/Bi2Mn2O6/rGO nanostructures for photocatalytic degradation of bromothymol blue (BTB), Congo red (CR) and photoinhibition of E. coli and S. aureus. A new solvothermal protocol was applied for the synthesis of ZnCe/Bi2Mn2O6/rGO nanomaterial. Important analytical techniques were applied for the characterization of the said nanomaterials. When allowed to visible light, the said nanostructure demonstrated excellent photocatalytic degradation of both the said dyes. The findings revealed that almost 99 % of both dyes were eliminated in just 30 min. In the absence of light, there was less than 60 % decline in both dyes even after 100 min. The ZnCe/Bi2Mn2O6/rGO was tested multiple times against the said dyes, and after seven cycles, its efficiency was reduced by only 15 %. Moreover, the nanostructures exhibited promising antibacterial properties by inducing photoinhibition of both E. coli and S. aureus bacteria. The inhibition zones of ZnCe/Bi2Mn2O6/rGO under visible light irradiation were measured to be approximately 17 ± 0.2 mm against E. coli and 19 ± 0.3 mm against S. aureus. These nanostructures effectively impeded bacterial growth and viability, underscoring their potential for applications in water disinfection and as antibacterial coatings. They are promising options for a variety of applications, especially as catalysts in many industries, due to their non-toxic nature and thermal stability. This work presents fascinating avenues for further investigation into the application of nanocomposites in healthcare and environmental preservation.

Porous Crystalline Organic Cages Made by Design

AbstractShape‐persistent organic cages are an intriguing class of molecular porous materials. Through hierarchical molecular design, size and shape of the intrinsic molecular voids are controlled by dynamic covalent chemistry, while pore structure and topology are governed by noncovalent alignment in the solid state. However, the predictable and reliable crystallization of organic cages is still challenging since long‐range superstructures are solely based on weak and rather unidirectional supramolecular interactions. In this tutorial review, we provide a general classification of porous solid‐state materials and discuss specific design principles regarding the dynamic covalent reactions, the small‐molecule building blocks and solid‐state engineering. Furthermore, we introduce the most important analytical techniques for porous materials with a special focus on organic cages.

Multipurpose new gas chromatography column based on pillararenes functionalized with imidazolium ionic liquids

BackgroundGas chromatography is worldwide recognized as one of the most important analytical techniques, due to its high versatility and reliability. The heart of a gas chromatograph is the column, that allows analyte peak separations and, consequently, accurate qualitative and qualitative analyses. New and more efficient columns are always requested to satisfy new and challenging analytical needs. ResultsIn this work, imidazolium ionic liquids functionalized pillar [5] arenes have been used for the first time as gas chromatographic stationary phases, considering their highly symmetric pillar-shaped architecture with cavities rich in π-electrons. Four imidazolium ionic liquids functionalized pillar [5] arenes have been tested as stationary phases with numerous analytes and isomers. In particular, one of these showed superior performances if compared to commercial columns, enabling challenging isomeric separations of halogenated benzenes, aromatic aldehydes, and aromatic anilines. Significance and noveltyTo our knowledge, this is the first report on the use of the ionic liquid P[n]A as a stationary phase in chromatography, either in GC or liquid chromatography (LC) separations. This work demonstrates the promising potential of ionic liquid P[n]A stationary phases for chromatographic separations.

Molecular Dynamics-Based Modeling of Ion-Neutral Collisions in an Open Ion Trajectory Simulation Framework.

Ion mobility spectrometry (IMS) and ion mobility mass spectrometry (IMS-MS) methods have become increasingly popular and are important analytical techniques to determine information about the structural parameters of gas-phase analytes. The accurate description of the interaction between molecular ions and neutral background gas particles is an essential part of high-quality simulations of such modern mass- and ion-mobility-spectrometric systems. Established ion-neutral collision models (Hard-sphere collision modeling and statistical diffusion simulations) in common ion-trajectory simulation systems like SIMION use strongly simplified assumptions and are thus limited in their predictive ability. In contrast, collision cross-section (CCS) modeling programs (e.g., MOBCAL, IMoS, and Colloidoscope) allow high-quality ion mobility predictions for low-field equilibrium conditions using explicit scattering processes with a molecular dynamics-based trajectory method but cannot be used for nonequilibrium collision modeling in an ion trajectory simulation. This work presents an extension to the open-source Ion Dynamics Simulation Framework (IDSimF), which allows the simulation of ion dynamics under arbitrary and even nonequilibrium conditions. It was extended by an advanced collision model employing the molecular dynamics trajectory method for a detailed microscopic description of ion-neutral collisions within ion-trajectory simulations. We used drift tube ion mobility spectrometry (DT-IMS) to validate the predictive abilities of the model and to estimate the runtime requirements for productive simulations. Simulated high-field ion mobilities for small ion systems in a drift tube IMS are compared to experimental values from the literature and an implementation of a hard-sphere model in IDSimF for helium and argon as background gas particles. Significant improvements in ion mobility predictions using the molecular dynamics trajectory approach are obtained with deviations of only a few percent from experimental values. Therefore, the established and publicly available MD collision model will serve as foundation for nonequilibrium ion dynamics simulations and the development of improved ion dynamics modeling methods.

Evaluation of Herbal Formulation of Saaranai Chooranam Through Fourier Transform Infrared Spectroscopic Study

Background: The Siddha system of medicine is purely scientific and the peculiar complex system of science and philosophy. Fourier Transform Infrared Spectroscopy (FTIR) is certainly one of the most important analytical techniques for herbal medicine. FTIR can be implemented during herbal drug development in production for process monitoring or in quality control laboratories. Aim & Objective: The aim of study is to evaluate the morphology and elemental characterization of the Saaranai chooranam. The functional groups of their formulations are analysed through FTIR spectroscopy and the biological roles of the functional groups are discussed in this study. Materials and methods: The raw drugs is collected and purified as per Siddha literature. Drug Saaranai chooranam, which has been illustrated in the text Dr.S.Venkattarajan, Akasthiyar-2000, Part – III, Page: 102, for the management of Raththa Kothippu (Systemic Hypertension). Results: The Fourier Transform Infrared Spectroscopy compounds showed the presence of functional groups O-H Stretching (Alcohol), C-H Stretching (Alkane), O=C=O Stretching (Carbon dioxide), C-C bending (Alkene), O-H bending (Carboxylic acid), C-O Stretching (Aromatic ester), C-O Stretching (Tertiary alcohol), S=O Stretching (Sulfoxide), C-H bending (1,2-disubstituted) and C-1 Stretching (Halo compound) which ensures the therapeutic effect of the drug. Conclusion: The instrumental analysis FT-IRS study of Saaranai chooranam is the presence of functional groups through the stretch and bends which is responsible for its functional activity. The functional groups in Saaranai chooranam have diuretic and nervin tonic activities. This will ensure the efficacy and therapeutic effect of the drug.

Green microextraction methodologies for sample preparations

Microextraction for analytical sample preparations became a reality with the introduction of solid phase microextraction (SPME) in 1987–90, followed by the development over the next two decades of the liquid phase microextraction (LPME) modes: single drop microextraction (SDME), hollow-fiber microextraction (HF-LPME), electromembrane extraction (EME) and dispersive liquid-liquid microextraction (DLLME). Parallel to the developments of SPME and LPME, more sensitive instrumentation and environmentally friendly solvents were also being developed, requiring reduced sample amounts and solvent volumes. Automation, using standard instrumental autosamplers, fluid techniques and 96 well plate systems, has further enhanced microextraction methods. Over the last decade, a further reduction in sample size and extraction volume, along with automation, has been possible with the development of microfluidic systems. A crucial companion to this progress has been the introduction of tools for assessing the relative overall greenness of analytical microextraction methods, which should be used in comparing proposed methods with published procedures. In this review we provide the reader with categorized lists of microextraction reviews and application papers, which contain hundreds of additional references, as an aid to accessing needed information for use in further developments of these important analytical techniques.

Construction of hierarchical Tourmaline@ZnO/MWCNT micro-nanostructured composite and its conductometric gas sensibility for N-butanol detection

Modification of traditional metal oxides to prepare gas sensors with excellent response and high selectivity for monitoring air pollution, is a pivotal indicator for the development of gas sensing technologies. In this research, the core-shell Tourmaline@ZnO/MWCNT micro-nanostructured composite was successfully constructed and prepared by the uniform co-precipitation and hydrothermal methods, which effectively achieved the high sensitivity to n-butanol. The structure, morphology and surface electron valence state were characterized by employing important analytical techniques. With tourmaline as the inner-core and MWCNT-interspersed ZnO nanosheets as the outer-shell, the uniquely hierarchical micro-nanostructure covered a larger specific surface area, which provided more active sites during the reaction. Meanwhile, the performance assessments demonstrated that the proposed micro-nano structure exhibited exceptional gas-sensing properties, while Tourmaline@ZnO/ 0.9%MWCNT sensor reaching the highest response value to 185.8–100 ppm n-butanol far exceeding other detected gases, additionally with a faster response-recovery time. The presence of tourmaline and the interspersion of MWCNT played a synergistic effect on the enhancement of the properties for ZnO-based gas sensors, which brought about a beneficial impact on the carrier transport. This technical strategy should be of certain significance in the intelligent preparation and extensive application of high-performance sensing devices in the future.

Investigation of Hydrogen Electrode Formation on the Surface of Noble Metals (Pd, Ir, Au) Exposed to Nitrogen Atmosphere: A Comprehensive Study Using Scanning Kelvin Probe

The importance of hydrogen evolution reaction (HER) in engineering and energy conversion related applications grows stronger and it is important to develop better catalysts to enhance the efficiency of the catalytic process. The introduction of computational chemistry (e.g., DFT) into the field of electrochemistry allows general prediction and understanding of activity trends. Great progress is made in modelling the electrochemical double layer under potentiostatic control [1]. However, a reliable and feasible experimental methodology providing in-depth experimental data for improving the theoretical model is lacking, as the electrochemical interface is usually buried under bulk electrolyte, which prevents most important surface analytical techniques to be applied for its investigation. However, it could be recently shown that a hydrogen electrode forms on a palladium surface even in nitrogen atmosphere, even at very low humidity [2] . The electrochemical double layer of this “hydrogen electrode in the dry” is confined just 1-2 monolayers of adsorbed water. However, it is still fully polarizable by adjusting the hydrogen activity from the backside of the electrode and it is even possible to measure full current-potential dependencies for reactions such as e.g. oxygen reduction [3]. Hence, this could be revolutionary new approach for investigating electrochemical electrodes in operando by standard surface analytical techniques. For this however, it needs to be investigated in how far this approach can be also applied beyond palladium. Since the potential of such “electrodes in the dry” cannot be measured with standard reference electrode a Kelvin probe is used instead [2,3]. Basically, the Kelvin probe measures the Volta potential difference between sample and probe (ψ KP - ψ S), and upon suitable calibration such measurement provides the electrode potential of the sample.Evers et.al has proposed the “Hydrogen electrode in dry” concept based on adjusting the hydrogen activity (cathodic charging) from one side of a palladium sample and measuring the work function on the other side using Kelvin probe [2]. In this work, the hydrogen electrode formation in dry (<0.1% R.H) as well as humid condition (>95% R.H) for Palladium (Pd), iridium (Ir) and gold (Au) was carried out using scanning Kelvin probe method by electrochemical charging of hydrogen from entry side and subsequently measuring the Volta potential on exit side (see fig.1). The measured potential on the exit side can be related to electrode potential. Palladium showed a 1:1 correlation between applied potential and measured potential at higher hydrogen activities (between 0 to 300 mVSHE) by establishing electrochemical equilibrium in both conditions, in accordance with [1]. Though the partial pressure of water is very low (0.23mbar) in dry condition, still the hydrogen electrode formation occurred on the palladium. In the case of Ir, it shows 1:1 correlation only in humid condition and not in dry condition. Further, the hydrogen electrode formation on Ir at different partial pressures of water was investigated by controlling the humidity on the exit side of the sample and the obtained results can be attributed to slight differences of thickness of the water layer in the monolayer and even sub-monolayer range. A linear decrease in the potential was observed when increasing the humidity from low to high humidity and the correlation between potential applied from the back and potential measure in the “dry” shows a decrease in responsiveness with decreasing humidity. No correlation was observed for iridium in dry conditions and it can be attributed to presence of insufficient amount of adsorbed water. For gold no correlation was observed in both the conditions. However, a slight behavior was observed at very high activities of hydrogen. This may be due to the initial hydrophobicity of gold, which has first to overcome by a formation of a double layer. On the whole, the effect of water layer adsorption on different metals and its influence on the establishment of a hydrogen electrode at a dry surface was studied.

A Brief Review of Chromatography in Croatia

Although the Republic of Croatia is a relatively small country geographically, it can boast numerous scientists who have left indelible marks in various scientific fields. However, this paper is exclusively about chromatography as one of the most important analytical techniques of our time. The development of chromatography in the Republic of Croatia and the role that three institutions have played in it—the Faculty of Chemical Engineering and Technology of the University of Zagreb, the Croatian Society of Chemical Engineers, and the Central European Group for Separation Sciences—will be briefly discussed.

Uranium in groundwater in parts of India and world: A comprehensive review of sources, impact to the environment and human health, analytical techniques, and mitigation technologies

Uranium concentration/contamination in groundwater is currently a subject of concern all over the world due to related severe health problems to humans, as groundwater is the main drinking water source in rural and urban India and also in several parts of the world. Uranium concentration in groundwater in shallow aquifers in various states such as Punjab, Rajasthan, Karnataka Telangana, and Madhya Pradesh of India varies from 0 to 1443 ng/ml exceeding the permissible levels by WHO for drinking water (30 ng/ml), at several places. Very high concentrations ranging up to 1400 ng/ml were reported in some areas in other countries such as Canada, the USA, Mongolia, Burundi, Zambia, Nigeria, South Korea, Pakistan, Jordon, Afghanistan, China, and Myanmar. Various natural aspects which influence the uranium concentration in groundwater such as bedrock geology, water chemistry, and redox conditions, and anthropogenic sources such as mining activities (uranium, coal, and phosphate rock), nuclear activities, agricultural practices of using phosphate fertilizers, and prevalence of excessive nitrate in some areas, are described with examples. Some of the important analytical techniques for the precise and accurate determination of elemental and isotopic concentrations of uranium in water samples, such as LED fluorimetry, Raman spectroscopy, inductively coupled plasma mass spectrometry (ICP-MS), high-resolution ICP-MS (HR-ICP-MS), and multi-collector ICP-MS (MC-ICP-MS), are described. A number of advancements have taken place in remediation technologies for the removal of uranium in drinking water using different physical, chemical, and biological methods including rainwater harvesting. Various mitigation strategies for the effective removal of uranium from water during treatment, such as bioremediation using biochars from different sources, nanoparticle technology, and adsorption by magnesium (Mg)-iron (Fe)-based hydrotalcite-like compounds (MF-HT), are described in detail.

Designing and investigation of enhanced photocatalytic and antibacterial properties of 3d (Fe, Co, Ni, Mn and Cr) metal-doped zinc oxide nanoparticles

In the present study, transition metal (Fe, Cr, Ni, Co and Mn)-doped ZnO nanoparticles (TM-ZN NPs) were synthesized via the chemical co-precipitation method. The effect of TM doping on the photocatalytic and antibacterial activity of ZnO (ZN) nanoparticles has been studied. Important analytical techniques characterized the synthesized materials. The XRD analysis verified the TM doping in ZN and confirmed the wurtzite hexagonal structure of ZN and TM-ZN NPs. SEM and TEM studied the synthesized samples' morphology and size, and the compositional analysis was performed by EDX spectroscopy. TM-ZN NPs showed enhanced photocatalytic and antibacterial activity than ZN NPs. In particular, Mn-doped ZnO nanoparticles (MnZN NPs) exhibited the highest bactericidal efficiency against Gram-negative and Gram-positive strains and maximum MB photocatalytic degradation (98% in 120 min) under sunlight irradiations. The notable increase in the photocatalytic and antibacterial activity of the synthesized TM-ZN NPs might be attributed to a decrease in their bandgap and suppression of e-h pairs recombination due to the induction of additional energy levels below the CB of ZN. The MnZN NPs showed good photocatalytic stability even after six consecutive cycles. Furthermore, a conceivable bactericidal and MB degradation mechanism over the MnZN NPs has been suggested.

Quinoline-3-Carboxylic Acids: A Step Toward Highly Selective Antiproliferative Agent.

The 2-styrylquinoline-3-carboxylate derivatives have been reported as antiproliferative agents. The aim of the study was to enhance the selectivity of the drug to the cancer cells. The change in pKa value can be the boost point to enhance the selectivity. The selectivity of the drug will enhance concentration in the cancer cells and will reduce the absorption in the non-cancerous cells. The designed hydrolysis of the ester group was obtained through the reported method to change the physiological properties, which was correlated with the in silico and in vitro selectivity studies. The compounds were characterized through important analytical techniques, moreover, the biological results of all compounds were obtained through in vitro cancer (MCF-7 and K562) and non-cancerous (HFK293) cell line. The synthesized compounds exhibited micromolar inhibition with a higher selectivity than their ester parent compounds, however, the compound showed better activity to the cancer cell, because of the minimal distribution of the drug in the non-cancerous cells. The compound 2f and 2l were found more selective and potent. The designed 2, 4-disubstituted quinoline-3-carboxylic acid derivatives were evaluated in in vitro cancer (MCF-7 and K562) and non-cancerous (HEK293) cell lines. The most concern issue was resolved by changing the pKa value of compounds, which was calculated by the software base study. The selectivity was correlated with the previously reported ester molecules. The synthesized compounds were characterized by important analytical techniques. The unionized/nonpolar form in the acidic cancer tissue environment, which enhances the drug absorption ion in an acidic medium, was also proved through the in vitro results; hence the compound showed better activity to the cancer cells because of the minimal distribution of the drug in the noncancerous cells. The more selective or less toxic anti-cancer compounds 2f and 2l were reported with all relevant experimental results as in silico Quantitative Estimation of Drug-Likeness (QED) and Absorption, Distribution, Metabolism, Excretion, and Toxicity (ADMET).

Revisão sobre cromatografia líquida acoplada à espectrometria de massas aplicada à análise toxicológica de alimentos

A cromatografia líquida de alta eficiência (HPLC) acoplada à espectrometria de massas (EM) constitui-se como uma das mais importantes técnicas analíticas utilizadas na determinação de compostos não voláteis ou instáveis termicamente. A combinação de ambas une a excelência da separação do analito de interesse na matriz através da técnica da cromatografia líquida de alto desempenho, juntamente com a técnica da espectrometria de massas que confirma a identificação química. Dentre as alternativas disponíveis, a espectrometria de massas é a que melhor fornece as informações estruturais necessárias. O acoplamento entre estas duas técnicas dá origem a uma ferramenta analítica robusta, versátil e de grande potencial na análise qualitativa e quantitativa em toxicologia de alimentos. O presente artigo apresenta uma revisão de literatura que tem o objetivo de apresentar os fundamentos da aplicação do acoplamento da Cromatografia Líquida e Espectrometria de Massas na área de análise de alimentos.

Health Benefits of Ipecac and Cephaeline: their Potential in Health Promotion and Disease Prevention

Background: Cephaelis ipecacuanha and Cephaelis acuminate commonly called Ipecac are the important medicinal plants of Cephaelis species belonging to Rubiaceae family. Ipecac is cultivated throughout the world due to their vast of therapeutic applications in gastrointestinal disorders and poisoning cases. Methods: In the present review paper medicinal importance of Ipecac and their main active phytoconstituents cephaeline have been discussed and presented in concise manner to explore their hidden potential. Phytochemical aspects of Ipecac and overview of cephaeline have been also discussed in the present paper. However important Pharmacological activities of cephaeline on gastrointestinal tract, cardiovascular system, Zika virus, Ebola virus, leishmania and malaria have been mainly focused in the present paper. Further important analytical techniques of detection and separation of cephaeline have also been presented in the present paper. Present paper also contains information of Tissue culture techniques of Ipecac for the better production of cephaeline to fulfil the industrial demands. Results: Cephaeline is colourless crystalline active compound of Ipecac plant which is having chemical formula C28H38O4N2. Claimed pharmacological activities of Ipecac such as diaphoretic, expectorant and anti-amoebic are mainly due to the presence of alkaloidal class chemical emetine and cephaeline. Result also revealed that ethanol extract of Ipecac has been used as emetic agents. Phytochemical analysis of the Ipecac revealed the presence of emetine, cephaeline, protoemetine, psychotrine, emetamine, O-methylpsychotrine and psychotrine methyl ether. Pharmacologically cephaeline induces vomiting through acting on stomach lining but it is more toxic and irritant compared to the emetine. Conclusion: The presented information will be beneficial to the scientific communities to know the importance of Ipecac and their main active phytoconstituents cephaeline for the treatment of numerous health related complication.

Phytochemical and Pharmacological Insight on Sesamol: An Updated Review

Background: Nowadays, sesamol has emerged as an effective adjuvant therapeutic agent in the anticipation and therapy of various diseases. Sesamol, a natural phenolic compound is a major lignan isolated from the seeds of Sesamum indicum and sesame oil. Sesame oil is well known for its nutritional as well as their health-promoting properties. Methods: Several studies revealed that sesamol possesses significant antifungal, anti-inflammatory, antioxidant, and free radical scavenging, anticancer, neuroprotective, cardioprotective, antiaging, hepatoprotective and antidiabetic activity, etc. Results: The present review highlights the potential of sesamol as a novel medicinal agent for the treatment of numerous types of ailment. Conclusion: This review article also provides a brief idea about its uses, ethnomedicinally and commercially important analytical techniques, and its pharmacological activities.

Types of Mycotoxins and different approaches used for their detection in foodstuffs

Mycotoxins are toxic complexes generated by various genera of filamentous fungi and pose severe public health hazards due to their carcinogenic and mutagenic properties. Toxigenic fungi produce mycotoxins on various foodstuffs when favorable conditions for their production are exist. The most important mycotoxin-producing fungal genera are Aspergillus, Fusarium and Penicillium. The major mycotoxin of concern, including aflatoxins, trichothecenes, ochratoxins, patulin, fumonisins, and zearalenone, are expressively contaminate foodstuffs, with implications for human and animal health. There are various environmental factors influencing mycotoxin production involving temperature, water activity, animal type, aeration, pH, light, and nature of substrate. The temperature and relative moistness range for ideal mycotoxin generation may shift from that steady fungal development. The high temperature and moistness stress primarily have a potential issue. A full understanding of the existence of mycotoxins in addition the implementation measures to overcome their contamination of foodstuffs is crucial. There are different important analytical techniques to precisely screen the levels of mycotoxins contamination and give a wider overview about what is the most common, pathogenic; along with further strategies to control measures. Thus, in this review sampling, sample preparation and different analytical methods for determination of mycotoxins have been discussed.

Highlights of Spectroscopic Analysis – A Review

Spectroscopic techniques are broadly employed to study the chemical structure of an analyte accurately. The electromagnetic radiation used in each method is allowed to interact with the molecule. The electric and magnetic property of the radiation is interacted with the similar properties of the chemical substance. Hence, the analyte is identified and characterized for the presence of atoms, bonds, functional groups, basic nucleus, molecular formula and molecular weight. The study is highly relevant to have a reference covering most of the important analytical techniques. The investigation implies content of basics for the interpretation of a spectrum, rules/laws followed, sampling techniques, sample cells, mechanism involved in analysis, units of measurements, spectral ranges, light sources, nature of samples to be analyzed, kind of solvents utilized, appearance of spectra and major uses of individual spectroscopic analysis. This also includes every significant aspect of various spectroscopic methods and represents qualitative &amp; quantitative parameters which insists for the research and experiments carried by the specific spectral process. Thereby, review regarding combination of entire spectroscopic principle, instrumentation and applications will be giving fruitful information to all analytical persons Pharma students.&#x0D;

INVESTIGATION AND ANALYSIS OF TWO COPTIC TEXTILE FRAGMENTS IN THE AGRICULTURAL MUSEUM IN EGYPT

The present study addressed important investigation and analytical techniques used in assaying the deterioration phenomena and identifying the components of two degraded Coptic textile fragments preserved in the Agricultural Museum in Egypt. The first fragment dates to the 2nd-3rd century AD, the second one dates to the 5th-6th century AD. The study used stereo microscope (SM), scanning electron microscopy coupled with energy dispersive x-ray spectroscopy unit (SEM-EDXS), high-performance liquid chromatography coupled with diode array detection and mass spectrometry (HPLC-DAD-MS), and Fourier transformer infrared spectroscopy by attenuated total reflection (FTIR-ATR) to examine the objects. The results revealed that the objects were made from natural wool, dyed with natural dyes, namely indigo, madder, and weld, and ornamented with small blank linen threads. The weaving structure is the tapestry technique with a little embroidery lace in the first fragment. The analytical results revealed that the fragments suffered from extensive deterioration, due to dust, soiling matters, stains, holes, missing parts, old adhesive, brittleness, and high acidity.

Current and emerging analytical techniques for geochemical and geochronological studies

Progress in both basic and applied geochemical studies highly depend on the progress of the analytical instrumentation in general. In recent times, there have been spectacular developments in different instrumental analytical techniques used for accurate determinations of elemental/isotopic abundances from per cent levels to pg/g levels in a variety of geological materials. Some of the important instrumental analytical techniques which are currently in use for geochemical studies include atomic absorption spectrometry (AAS), inductively coupled plasma atomic emission spectrometry (ICP‐AES), recently introduced microwave plasma‐atomic emission spectroscopy (MP‐AES), X‐ray fluorescence spectrometry (XRF), instrumental neutron activation analysis (INAA), inductively coupled plasma mass spectrometry (ICP‐MS), ICP‐time of flight mass spectrometry (ICP‐TOF‐MS), high resolution inductively coupled plasma mass spectrometry (HR‐ICP‐MS), and multi‐collector‐ICP‐MS (MC‐ICP‐MS), with each one having its own merits and the limitations. Developments in sensitive high‐resolution ion microprobe (SHRIMP) opened up zircon geochronology and has revolutionized age dating of rocks byin‐situisotopic analysis on single mineral grains such as zircons. Recently emerged MC‐ICP‐MS in combination with collision/reaction cell is allowing detection of small variations in natural isotopic compositions of non‐traditional stable isotopes. Advancements in other microanalytical techniques such as laser ablation‐ICP‐MS (LA‐ICP‐MS), electron probe micro‐analyser (EPMA), scanning electron microscopy and energy dispersive X‐ray spectroscopy (SEM‐EDS), laser‐induced breakdown spectroscopy (LIBS), have markedly improved direct solid analysis,in‐situprobing of individual minerals, fluids, and melt inclusions. Raman spectroscopy is currently emerging as a powerful geochemical analytical tool. Some interesting combination instruments such as ICP‐MS/AES showed synergic benefits when used in geochemical studies. There is also substantial progress in other critical areas such as sample preparation, sample decomposition, development of geochemical reference materials, and quality issues in general. Miniaturization is perhaps the most notable current trend in analytical techniques, and their use in exploration studies provide near‐real time sampling guidance in the field. In this review, all these aspects are updated, summarized and discussed at depth with practical examples. However, most of these instruments are expensive and complex and future developments may focus on some of the drawbacks of the current systems to realize their full potential for geochemical/geochronological studies.

Synthesis of CuO-NPS by simple wet chemical method using various dicarboxylic acid salts as precursors: Spectral characterization and in-vitro biological evaluation

In this study, a simple chemical reduction method was employed to synthesize CuO-NPs. Various dicarboxylic acids were converted into Cu(II) salt of dicarboxylic acid which were used as precursors. NPs were produced by reducing precursors with NaBH4. Characteristics of synthesized NPs were investigated by using important analytical techniques including Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermo gravimetric analysis (TGA) and scanning electron microscopy (SEM). Developed NPs were investigated for their antibacterial activity against a range of bacterial strains by employing agar well diffusion method. CuO-NPs exhibited good to moderate activity against E-Coli, B. Subtilis and poor activity against K. pneumonia and Methicillin-resistant Staphylococcus aureus (MRSA). It was found that amongst all experienced compounds sample 2 showed good activity with minimum inhibition concentration (MIC) 10 µg/mL (zone of inhibition: 22± 0.12 mm) while sample 3 showed poor activity with MIC 40 µg/mL (zone of inhibition: 8.0 ± 0.18 mm).&#x0D; &#x0D; KEY WORDS: CuO-NPs, Dicarboxylic acids, Sodium borohydride, Antibacterial study&#x0D; &#x0D; Bull. Chem. Soc. Ethiop. 2020, 34(2), 323-334&#x0D; DOI: https://dx.doi.org/10.4314/bcse.v34i2.10