Inductively Coupled Plasma Optical Emission Spectrometry Research Articles

Trace element concentrations and associated human health risk assessment in canned tuna, city of Neyshabur, Iran

Seafood is considered a healthy and nutritious food, but the presence of toxic substances in such foods is a serious problem. The present study aimed to analyze the concentration of some toxic metals in seafood and evaluate their noncarcinogenic risks to consumers. Samples were digested according to the Association of Official Agricultural Chemists (AOAC) standard. The heavy metals concentration of Cd, Ni, Hg, Pb, and Sn in 30 canned tuna samples were determined using an inductively coupled plasma optical emission spectroscopy (ICP-OES). The mean concentrations of Cd, Ni, Sn, Pb, and Hg were 0.7, 0.49, 1.03, 0.31, and 0.12 µg g− 1, respectively. Based on these results, the concentrations of Cd, Sn, and Hg in samples met the required standards. However, the concentrations of Ni and Pb in some samples were higher than the permissible limits. The mean values of Sn, Ni, Pb, Hg, and Cd in samples followed a decreasing order. Since the values of the health risk index for these samples were lower than the HI and HRI risk threshold (<1), they can be consumed without any problems arising. Highlights The metal concentration was measured in the four most popular brands of canned fish sold in Neyshabur City, Iran. Some samples exceeded the maximum permissible level of nickel (Ni) and lead (Pb). A significant correlation was observed between Ni concentration with Pb and Hg concentrations and Pb concentration with Cd concentration. The values of the health risk index (HRI) for noncarcinogenic health risks were lower than 1. The calculated Hazard index (HI) for adult and child consumers was less than 1. The HI values were greater for children than for adults.

Comprehensive risk assessment of lead concentrations in chicken, quail, and duck egg albumen and yolk using Monte Carlo simulations

This study conducted a comparative analysis of the concentration of the lead (Pb) in the albumen and yolk of eggs from domesticated chicken, quail, and duck, with a concurrent assessment of the potential carcinogenic and non-carcinogenic risks associated with the consumption of eggs sourced from Türkiye. A total of 78 poultry egg samples were gathered from breeding farms and farmers' markets situated in Şanlıurfa province. Lead concentrations were assessed through inductively coupled plasma optical emission spectrometry (ICP-OES). Human health risk assessment adheres to the guidelines set forth by the United States Environmental Protection Agency (US EPA), which primarily emphasizes estimated daily intake (EDI), international lifetime cancer risk (ILCR), target hazard quotient (THQ), and Monte Carlo simulation (MCS) as a probabilistic approach. One-way analysis of variance (ANOVA) was employed to compare Pb concentrations within egg yolks and albumens, as well as among various types of eggs. The levels of Pb found in the albumen of chicken, quail, and duck eggs were measured to be 0.31 ± 0.11, 0.43 ± 0.11, and 0.47 ± 0.16 μg kg−1, respectively. The concentrations of Pb in the yolks of chicken, quail, and duck eggs were found to be 0.54 ± 0.19, 0.28 ± 0.11, and 0.69 ± 0.21 μg kg−1, respectively. These concentrations were below the maximum permitted levels set by the FAO/WHO. The results indicated that Pb content in all tested eggs was safe for consumption, with exposure levels significantly below Joint FAO/WHO Expert Committee on Food Additives (JECFA) risk thresholds. The THQ values were less than one, indicating no non-carcinogenic risk. In addition, this study provides accurate and reliable data for policy makers to improve food safety measures and reduce potential public health risks.

Preparation of 97% pure nickel-cobalt alloy from waste Ni-MH batteries by using waste glass as a fluxing agent

With the e-waste growing rapidly all over the globe due to growing demand of electronics, smartphones, etc., coming up with an efficient and sustainable recycling process is the need of the hour. The present work reports a novel and sustainable process of manufacturing Ni alloy by bringing together three major waste streams such as waste Ni-MH batteries, e-waste plastics, and waste glass. The chosen temperature (1550 °C) favours the reduction of nickel-oxide by e-waste plastic as the reductant and sends rare earth elements present in the waste Ni-MH battery as oxide mixture to the slag phase. Waste glass powder used in this process functions as the fluxing agent, hence not requiring any additional flux. The reduction mechanism is gas-based, controlled mainly by hydrogen and carbon monoxide gases released as a result of decomposition of e-waste plastic as reaction commenced from cold zone (∼300 °C) to hot zone (1550 °C) in the horizontal tubular furnace. Formation of nickel alloy and enrichment of slag with mixture of rare earth oxides were confirmed by XRD, SEM-EDS, and Rietveld refining analysis performed on the XRD spectra of slag phase. ICP-OES (Inductively coupled plasma optical emission spectroscopy) and LIBS (laser induced breakdown spectrometer KT-100S) confirmed the high metal content in the alloy, thereby emphasizing the purity (∼98%) which is close to the composition of nickel super alloy. A maximum of 61% by weight REO enrichment was achieved in the slag phase, having La2O3:44.6%, Pr2O3:14.8%, and Nd2O3: 1.6% under optimised experimental conditions (1550 °C, 15 min, and 20% waste glass powder). This scientific investigation evinces a promising route for efficient utilisation of waste streams emanating from e-waste, thereby devising a sustainable recycling technique and protecting the environment, too.

Analysis of sulfur in soil and plant digests using methane as a reaction gas for ICP-MS

Quantitation of sulfur (S) is vitally important for analysis of agricultural soil and plant samples due to the requirement of S in living organisms. Although inductively coupled plasma mass spectrometry (ICP-MS) is a commonly used and robust instrument for multi-elemental detection, S is usually analysed by ICP-optical emission spectroscopy (OES) since S quantitation poses a particular challenge for ICP-MS due to interferences on all S isotopes. The requirement for analysis by two instruments increases time and cost for sample analysis, hence analysis by one instrument is desirable. The use of reaction gases in ICP-MS can improve the performance by shifting S to a mass for detection where no interference is present. This work explored the potential of methane as a reaction gas for analysis of S in soil and plant samples to give users an alternative option to oxygen. The product ion clusters CH2SH+ were monitored (m/z 47 and 49 on ICP-MS and with mass shift of +15 from Q1 → Q2 using 32 → 47 and 34 → 49 on triple quadrupole ICP-MS). As expected, triple quadrupole ICP-MS performed better than single quadrupole ICP-MS containing a reaction cell due to the ability to preselect the m/z of choice and remove ions that may react with methane in the reaction cell. The method detection limit (MDL) was 150 mg kg−1 S for plants and 53 mg kg−1 S for soils which is fit for requirements. This is the first-time methane has been reported as a reaction gas for analysis of S and shows promising results for agricultural samples when using a triple quadrupole ICP-MS. Results compared well to those obtained via the more commonly used ICP-optical emission spectroscopy (OES) method with results <20 % for all samples. Interlaboratory comparison samples were within 2 Z-scores of the consensus mean. In the absence of ICP-MS/MS, Q-ICP-MS with detection of cluster m/z 47 was deemed to be suitable for detection of S in plant samples, with acceptable MDL (250 mg kg−1 S), acceptable precision (<20 % RSD) and <20 % variation to the reported ICP-OES result.

Uncovering sediment pollution sources: A comparative assessment of two South African Estuaries

Richards Bay Harbour is South Africa's largest and busiest deep-water port by tonnage, and this ongoing shipping and port activities will expectedly result in metal contamination issues. The adjacent Mhlathuze Estuary is a nature reserve with a long history with Richards Bay Harbour and may be prone to metal contamination from multiple sources. The study investigates the sources of contaminated sediments in these two South African estuaries arising from their proximity to various anthropogenic activities. Investigating these sources of contamination is crucial for developing effective pollution control strategy since Richards Bay Harbour and Mhlathuze Estuary are regarded as estuaries of national conservation importance in South Africa. To provide further insights, sediment samples were acid digested and quantified for metal concentrations using Inductively coupled plasma-optical emission spectrometry (ICP-OES). Multivariate (SIMPROF and cluster) analysis was used to identify how sampling sites in Richards Bay Harbour and Mhlathuze Estuary were grouped based on sediment metal concentrations. Results of pollution load index for Richards Bay Harbour showed site 4 to be heavily polluted, while site 3 in Mhlathuze Estuary showed moderate pollution. Multivariate analysis (SIMPROF and cluster) further revealed sites related to anthropogenic activities and those that were unpolluted. Engaging this advanced analysis enhanced the ability to delineate potential pollution sources and further helped in the identification of the main contributors to sediment pollution. The findings indicate that port and industrial activities are the major contributors to sediment contamination at the estuaries. The results provide specific insights into the sources of pollution, informing targeted environmental management and policy-making efforts to protect and improve the estuarine environments.

Modeling and simulation for the sustainable recovery of aromatics (BTX) from petrochemical industrial wastewater.

Petrochemical wastewater is a major industrial source of pollution that produces a variety of toxic organic and inorganic pollutants, naturally present or added during the process. These pollutants are a serious threat to the soil, water, environment, and human being due to their complex and hazardous nature. Glycols such as monoethylene glycol (MEG), diethylene glycol (DEG), triethylene glycol (TEG), and aromatics (BTX-benzene, toluene, and xylene) are the most common organic impurities present in petrochemical wastewater. The objective of this paper is to recover aromatics and water from petrochemical industrial wastewater. The reclamation process is used to remove inorganic impurities such as heavy metals Fe, Zn, Pb, Mn, Al, Ni, As, Cr, Cu, Cd, and K and salts. In the present work, 1% sodium bi-carbonate (NaHCO3) is used to precipitate the inorganic impurities present in the wastewater at 40°C atmospherically. Aspen Hysys simulation software is used for modeling and simulation for the treatment process using NRTL (non-random-two-liquid) thermodynamic model. The process generated from Aspen Hysys is validated with lab experiments. To support global sustainable development, this study is focused on reducing, reusing, and recycling separation techniques such as centrifuge separation and vacuum distillation have been used. The characterization of regenerated water was performed using ICP-OES (inductively coupled plasma-optical emission spectroscopy) to determine the reduction in heavy metals. It was found that > 99.5% of heavy metals were removed. The regeneration of these aromatics is necessary for economic and environmental reasons so that it can be reused to avoid its disposal in and contamination of natural environments.

Reactive Condensation of Cr Vapor on Aluminosilicates Containing Alkaline Oxides

This study is part of a series with the objective of improving fundamental understanding of reactive condensation of Chromium (Cr) vapors, which are generated from Cr containing alloys used in many high-temperature (>500 °C) process environments and can form potentially problematic condensed hexavalent (Cr(VI)) species downstream. This study specifically focuses on the effects of alkaline oxide additives in aluminosilicate fibers on Cr condensation and speciation. Cr vapors were generated by flowing high-temperature (800 °C) air containing 3% water vapor over chromia (Cr2O3) powder, with aluminosilicate fiber samples positioned downstream where the temperature decreases (<500 °C). Total condensed Cr and ratios of oxidation states were measured using inductively coupled plasma optical emission spectroscopy (ICP-OES) and diphenyl carbazide (DPC) colorimetric/direct UV–vis spectrophotometric analyses. Results indicate presence of hexavalent Cr (Cr(VI)) species condensed on all samples investigated. The ratio of Cr(VI) to total Cr detected was consistently higher on aluminosilicate fiber samples containing alkaline oxide (CaO and MgO) additions. Computational thermodynamic equilibrium modelling corroborated experimental results showing stabilities of Ca and Mg chromate (Cr(VI)) compounds. Comparative results and analyses are presented and discussed to help inform mechanistic understanding and future related research and engineering efforts.

Steam reforming of dodecane using Ni-red mud catalyst: A sustainable approach for hydrogen production

Conventional energy sources emit huge amounts of carbon dioxide (CO2) into the atmosphere causing global warming. Hydrogen (H2) is an alternative clean energy carrier that produces only heat and water vapor upon combustion. In this work, we utilized industrial waste material (Red Mud, RM) to develop a cost-effective and efficient catalyst for steam reforming of diesel (n-dodecane as a model compound) for hydrogen production. We impregnated nickel (Ni), a prudent and effective metal, in red mud (RM) in varied proportions to employ as a catalyst for hydrogen production. The catalysts' structure was characterized by powdered X-ray Diffraction (PXRD), Fourier Transform Infrared spectroscopy (FTIR), and X-ray Photoelectron Spectroscopy (XPS). Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) and Electron Dispersive Spectroscopy (EDS) were used to measure the elemental composition while Scanning Electron Microscopy (SEM) was used to investigate the catalysts’ morphology. Surface area and porosity were analyzed using the N2 adsorption/desorption isotherms, and H2-Temperature Programmed Reduction (H2-TPR) to study the reducibility and interaction of Ni species to the RM. The catalysts were then evaluated for hydrogen production by the steam reforming process of n-dodecane (SRD). It was found that the catalyst with 20% Ni loading (20% Ni@RM) can produce hydrogen with selectivity as high as 75%, and stability for 20 h with a negligible decline in the catalyst performance.

Microwave-induced plasma optical emission spectrometry (MIP-OES) analysis of the major elements in woody biomass ash following microwave acid digestion

The increasing use of woody biomass for sustainable heat and power is generating large amounts of woody biomass ash (WBA), which needs to be safely disposed of or recycled. In this study, the utility of Microwave-induced plasma optical emission spectrometry (MIP-OES) with microwave-assisted acid digestion for simplifying analyses of the major elements of WBA was investigated. Calibration curves exhibited good linearity (R2 > 0.999). Internal standardization using three emissions lines (324.754 nm of Cu, 451.131 nm of In and 371.029 nm of Y) showed that calibration with Cu (324.754 nm) correction resulted in the best linearity. Physical effects, even the presence of hydrofluoric acid or boric acid in mixed acids used for digestion, were of trivial influence with internal standard recoveries were within 0.95 to 1.05 times those of the blank sample. The limit of detection of MIP-OES for seven measured elements was 0.85–89 μg/L, 0.23–2.8 times higher than that of inductively coupled plasma optical emission spectrometry (ICP-OES). The recovery of elements in a certified fly ash reference material as determined by MIP-OES was 0.80–1.08. Elemental quantification of WBA samples by MIP-OES showed a strong correlation with that by ICP-OES. However, in a Welch's t-test, the MIP-OES values were significantly higher for K and significantly lower for Al and Ca in a majority of the samples. Nonetheless, considering the good correlation between their results, MIP-OES can replace ICP-OES for the analysis of WBA.

Investigation of mercury contamination in lipstick sold in the Saudi market and the potential health risk

Background: Environmental contamination is a significant global health issue, with cosmetics and pharmaceuticals being major polluters. High concentrations of heavy metals, such as Hg, have been found to have toxic effects and may pose a threat to human health. This study aimed to determine the concentration of mercury (Hg) in lipsticks available in the Saudi Arabia market. Methods: In this study, 12 lipstick samples from three colors were analyzed using inductively coupled plasma optical emission spectrometry (ICP-OES) to measure the content of Hg. Results: The concentration range of Hg was 0.004–0.296 ppm. Moreover, the systemic exposure dosage of mercury in the lipstick samples examined in this study ranged from 5.01 × 10−8 to 1.43 × 10−6 μg/kg bw/day, while the range of the margin of safety was from 7.3 × 109 to 2.2 × 108. Discussion: The Hg concentration in all analyzed samples was less than 0.50 and 1 ppm, which indicated that the Hg level was within acceptable limits according to Saudi Standards, Metrology and Quality Organisation (SASO) and the United States Food and Drug Administration (US FDA), respectively. On the other hand, the calculated margin of safety values for mercury exceeded the safe standard established by the WHO. The results derived from using hazard quotient (HQ) indices depict the potential carcinogenic health risk posed to consumers who employ red-colored lipsticks.

Validation of high-resolution continuum source flame atomic absorption spectrometry for determination of selected toxic and potential toxic metals in the decontamination process of wastewater discharged in natural receivers.

A new method based on high-resolution continuum source flame atomic absorption spectrometry (HR-CS-FAAS) was validated for the determination of selected toxic and potentially toxic metals in wastewater resulting from mining activity. The results were compared with inductively coupled plasma optical emission spectrometry (ICP-OES). The HR-CS-FAAS method was characterized by detection limits in the range (µg L-1) 0.9(Mn)-33.6(Pb), better than ICP-OES for Cu, Fe, Ni, Co, Pb and Mn, and poorer for Cd, Zn and Cr. The Dunnett's and Tukey's statistical test showed that both methods were not affected by significant bias against certified value and between them. The recovery in HR-CS-FAAS method was in the range of 98-103% with relative extended uncertainty of 9-25%, and precision of 1.5-14.1%. The results indicated that the HR-CS-FAAS method is suitable for the determination of toxic and potentially toxic elements directly in filtered water samples without any chemical treatment.

Robust carbon quantum dots supported cobalt oxide composite particles prepared by hydrothermal process for green hydrogen generation via sodium borohydride hydrolysis

Carbon quantum dots (CQDs), a new class of carbon nanostructures with a particle size of 10 nm, exhibit important properties such as easy surface functionalization, low cost, chemical inertness, water solubility and low toxicity. In this study, an effective catalyst was synthesized using cobalt oxide (Co3O4) metal nanoparticles dispersed on CQD support material obtained from sucrose by hydrothermal method (Co3O4-SCQD-HT). The resulting catalyst system was used for effective hydrogen (H2) production from sodium borohydride (NaBH4) hydrolysis. Hydrogen generation rate (HGR) values of 7041, 18,426 and 27,555 mlmin−1gcat−1 were obtained with Co3O4-SCQD catalysts synthesized during the hydrothermal process with water, ethanol and methanol solvents, respectively. The HGR values of the catalysts obtained in ethanol and methanol medium provided an improvement of approximately 2.5 and 4 times, respectively, compared to the catalyst prepared in water medium. The activation energy for NaBH4 hydrolysis by Co3O4-SCQD-HT was 29.92 kJmol−1. Transmission Electron Microscopy (TEM), Energy-dispersive X-ray spectroscopy (EDS), nitrogen adsorption/desorption, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Inductively coupled plasma optical emission spectroscopy (ICP-OES) and X-ray photoelectron spectroscopy (XPS) analyses were used for the characterization study. The average particle size for the Co3O4-SCQD-HT nanocomposite is approximately 3.27 nm. The presence of carbon (C), oxygen(O), nitrogen (N) and cobalt (Co) atoms was confirmed by XPS and EDS analysis.

Employing a switching valve to automate external standard calibration in inductively coupled plasma optical emission spectrometry

The traditional external standard calibration method (EC) is automated and simplified using a four-port switching valve (SV4) and a multi-signal approach that enables the generation of several calibration points from a single calibration solution. The SV4-EC method is applied to inductively coupled plasma optical emission spectrometry (ICP-OES) and is based on gradient dilution taking place within the instrument's sample introduction tubing. Both the calibration solution and the samples are diluted by a blank solution containing an internal standard species. Forty-five dilution points are collected over time while the solutions are mixed. Instrument responses from the calibration solution are then plotted against those from the samples, and the slope of the calibration curve is used to determine the unknown analyte concentrations in the samples. The method is used to determine Ba, Co, Cr, Cu, Fe, Mn, Ni, V and Zn in coconut water, creek water, green tea, mouthwash, soft drink, vinegar, and vodka. Limits of detection are in the 0.0002–0.009 mg L−1 (n = 10) range, with precision on the order of 0.4 %–3 % RSD. Analyte percent recoveries from a 0.5 mg L−1 spike are in the ranges of 88.4 %–111 %, 88.9 %–111 %, and 88.0 %–111 % for EC, SV4-EC, and the internal-standard-corrected method (SV4-EC/Sc), respectively. No statistically significant difference is observed between EC and SV4-EC recoveries for any of the sample matrices evaluated. Comparable results between EC and SV4-EC were also found for the analysis of two certified reference materials, Bovine Liver and Oyster Tissue. Based on a single calibration solution, the SV4-EC method requires caution when preparing the calibration standard to minimize measurement bias.

Assessing Elemental Diversity in Edible-Podded Peas: A Comparative Study of Pisum sativum L. var. macrocarpon and var. saccharatum through Principal Component Analysis, Correlation, and Cluster Analysis

This study assessed eleven elements in 24 edible-podded peas, including sugar snap pea and snow pea genotypes aiming to identify promising parents for nutraceutical breeding. Elemental concentrations of pods (dry weight basis) were estimated through inductively coupled plasma-optical emission spectroscopy (ICP-OES). The ranges for these elements varied significantly, highlighting the diverse elemental profiles within the edible-podded pea genotypes. All the elements exhibited a high genotypic and phenotypic coefficient of variation along with considerable heritability and hereditary progress. Positive and significant correlations were recorded among all elements, suggesting the potential for simultaneous selection for these traits. Principal component analysis (PCA) revealed that the first two components accounted for 80.56% of the variation. Further, cluster analysis, based on Euclidean distance, grouped the 24 cultivars into two major clusters. Cluster I exhibited higher means for all estimated concentrations compared to Cluster II. Notably, Dwarf Grey Sugar and Arka Sampoorna from the snap pea group and PED-21-5 and Sugar Snappy from the sugar snap pea in Cluster II demonstrated superior elemental concentration in whole pods. The selected edible-podded pea genotypes serve as valuable genetic resources for new cultivar development, particularly in biofortification efforts targeting whole pod nutrient composition.

Valorization of ladle furnace slag and functional enhancement of post-adsorption materials

Carbonating metallurgical slags plays a pivotal role in achieving efficient mineral CO2 sequestration and waste valorization.This research introduces a novel integrated approach that combines the carbonation of Ladle Furnace Slag (LFS) with the simultaneous degradation of Methyl Orange (MO) in synthetic water. The comprehensive characterization of LFS was conducted using X-ray Diffraction (XRD), X-ray Fluorescence (XRF), Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES), Brunauer-Emmett-Teller (BET) analysis, and Scanning Electron Microscopy (SEM). The adsorption experiments reveal the high LSF capacity for MO degradation (149.25 mg/g) following pseudo-second-order kinetics (R2 = 0.99) and Langmuir isotherm (R2 = 0.98). The adsorption process was primarily governed by chemical and electrostatic interactions. Analysis of LFS-loaded MO indicated a reduction in Ca(OH)2phases, responsible for CO2mineralization and the formation of calcite (CaCO3). Furthermore, the study explored the reusability of LFS-MO composites through chemical and thermal modifications. Pyrolysis of carbonated LFS with KOH impregnation exhibited potential for regenerating Ca(OH)2phases, while thermal modification induced significant mineral and microstructural changes, creating new active sites at various temperatures. Additionally, the Fenton-like reaction followed by thermal modification resulted in a highly organized and microporous LFS structure with enhanced surface area and porosity. Moreover, modification with ZnSO4followed by thermal activation promoted the formation of ZnO nanoxides on the LFS surface. This research proposes an innovative carbonating approach for metallurgical slags and wastewater treatment, extending their utility and enhancing industrial sustainability. Carbonated LFS-MO composites hold promise for applications in construction, CO2capture, and wastewater treatment, thereby fostering sustainable industrial practices with ongoing research and development efforts.

Wild Mushrooms as a Source of Bioactive Compounds and Their Antioxidant Properties-Preliminary Studies.

Determination of active compounds by gas chromatography-mass spectrometry was carried out in addition to thermogravimetric determinations, quantitative determination of total polyphenols by spectrophotometry using Folin-Ciocalteu reagent, determination of antioxidant activity using 2,2-diphenyl-1-picryl hydrazyl radical (DPPH) and 2,2'-azino-di-[3-ethylbentiazoline sulphonated] (ATBS). In addition, spectrometric analysis of selected minerals and heavy metals was performed by inductively coupled plasma optical emission spectroscopy (ICP-OES). The mushrooms analysed varied in terms of their bioactive constituents. They contained components with varying effects on human health, including fatty acids, oleamide, 1,2-dipalmitoylglycerol, (2-phenyl-1,3-dioxolan-4-yl)-methyl ester of oleic acid, deoxyspergualin, 2-methylenocholestan-3-ol, hexadecanoamide, isoallochan, 2,6-diaminopurine, and adenine. All contained polyphenols and varying amounts of minerals (calcium, magnesium, iron, zinc, potassium, phosphorus, sodium, copper, silicon and manganese) and exhibited antioxidant properties of varying potency. No exceedances of the permissible concentration of lead and cadmium were observed in any of them. All of the mushrooms studied can provide material for the extraction of various bioactive compounds with physiological effects. In addition, the presence of polyphenols and minerals, as well as antioxidant properties and the absence of exceeding the permissible concentration of heavy metals, indicate that these species could be interesting material in the design of foods with health-promoting properties, nutraceuticals or dietary supplements. However, the use of the fruiting bodies of these mushrooms requires mandatory toxicological and clinical studies.

Exploring the potential of chitosan from royal shrimp waste for elaboration of chitosan/bioglass biocomposite: Characterization and “in vitro” bioactivity

Exploiting royal shrimp waste to produce value-added biocomposites offers environmental and therapeutic benefits. This study proposes biocomposites based on chitosan and bioglass, using shrimp waste as the chitosan source. Chitin extraction and chitosan preparation were characterized using various analytical techniques. The waste composition revealed 24 % chitin, convertible to chitosan, with shells containing 77.33-ppm calcium. (X-ray diffraction) XRD analysis showed crystallinity index of 54.71 % for chitin and 49.14 % for chitosan. Thermal analysis indicated degradation rates of 326 °C and 322 °C, respectively. The degree of deacetylation of chitosan was 97.08 % determined by proton nuclear magnetic resonance (1H-NMR) analysis, with an intrinsic viscosity of 498 mL.g−1 and molar mass of 101,720 g/mol, showing improved solubility in 0.3 % acetic acid. Royal chitosan (CHR) was combined with bioglass (BG) via freeze-drying to create a CHR/BG biocomposite for bone surgery applications. The bioactivity of the CHR/BG was tested in simulated body fluid (SBF), revealing a biologically active apatite layer on its surface. Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) analysis confirmed enhanced bioactivity of the CHR/BG compared to commercial chitosan. The CHR/BG biocomposite demonstrated excellent apatite formation, validated by Scanning Electron Microscopy (SEM), highlighting its potential in bone surgery.

Chitosan-stabilized gold nanoparticles decorated with a thiodiacetic acid nanoprobe for selective detection of arsenic(iii) in rice and water samples.

A sensitive and selective method for the detection of arsenic(iii) (As3+) based on chitosan-stabilized gold nanoparticles (CS/AuNPs) decorated with a 2,2'-thiodiacetic acid (TDA) nanoprobe was developed and used to detect and indicate the contamination of rice, drinking water and environmental water samples. AuNPs were reduced and stabilized with CS and subsequently functionalized with TDA. As3+ interacted with the carboxylate group of TDA to form an As-TDA complex, inducing the aggregation of CS/AuNPs@TDA. The aggregation of CS/AuNPs@TDA was accompanied with a change in color from red to bluish purple and a shift in surface plasmon resonance wavelength from 525 nm to 645 nm. The response for the detection of As3+ was linear at concentrations from 10 to 1000 μg L-1 with a limit of detection of 6.1 μg L-1. The method exhibited selectivity toward As3+ among various cations (As5+, Cu2+, Fe3+, Fe2+, Hg2+, Al3+, Cr3+, Cd2+, Co2+, Ni2+, Pb2+ and Zn2+) and anions (Br-, Cl-, F-, SO4 2-, NO3 - and PO4 2-). The CS/AuNPs@TDA nanoprobe was applied to detect As3+ in rice, drinking water and environmental water samples. The results were consistent with those obtained via inductively coupled plasma-optical emission spectrometry (ICP-OES). Satisfactory recoveries ranging from 88.22% to 105.74% (RSDs of 0.25-2.99%) were obtained from spiked samples.

Correlation between serum heavy metals and the risk of oral squamous cell carcinoma and oral potentially malignant disorders

Oral squamous cell carcinoma (OSCC) is a serious public health problem in various Asian countries, including Sri Lanka, and a combination of cultural practices, lifestyle factors, and genetic predispositions influences the incidence of these cancers. The examination of the connection between exposure to heavy metals and the probability of developing oral potentially malignant disorders (OPMD) and OSCC has been limited in its scope, and the overall consequences of such exposure remain largely unknown. This study aims to clarify the link between serum levels of heavy metals and the risk of OSCC and OPMD. The concentrations of seven heavy metals—namely, arsenic (As), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), lead (Pb), and zinc (Zn)—were analyzed in serum samples from 60 cases and 15 controls in the Sri Lankan cohort. The Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) was used for the analysis. Subsequently, the data underwent statistical evaluation via the Kruskal–Wallis H test, using the Statistical Package for Social Sciences (SPSS) version 28 software, with a confidence interval set at 95%. A p-value less than 0.05 was considered statistically significant. The cohort consisted of 48 men and 27 women, with 15 patients each diagnosed with OSCC, OSF, OLK, and OLP, and 15 healthy controls. The study used the Kruskal–Wallis Test to compare metal concentrations across groups, finding significant differences for all metals except As and Pb. Significant associations were observed between age, past medical history, drug history, gender, smoking, alcohol consumption, and betel chewing. The Spearman Correlation test showed significant correlations between the concentrations of Cr, Co, Cu, As, and Zn and the presence of cancer/precancer conditions. The study’s findings suggest that heavy metal contamination may be linked to the development of OSCC and precancerous conditions. When comparing OSCC and OPMD cases with controls, the serum concentrations of As and Pb did not differ significantly. However, Cd, Cr, Co, Cu, and Zn exhibited significantly higher concentrations among cases compared to controls (p < 0.05). This study observed significant variations in the levels of these five heavy metals among cancerous (OSCC), premalignant (OPMD), and healthy tissues, suggesting a potential role in the progression of malignancies. These findings underscore the importance of environmental pollution in this specific context.

Adsorption Dynamics of Disodium Octaborate Tetrahydrate on Clay Minerals: Implications for Construction Wood Protection.

The wood preservative disodium octaborate tetrahydrate (DOT) migration is studied in clay. Using boron analysis by inductively coupled plasma optical emission spectroscopy (ICP-OES), DOT spatial and temporal dynamics are surveyed to show how DOT permeates into the wood and the clay using concentration profiles as a function of depth, initial wood moisture, and direction of filling. Atomic force microscopy and chemical imaging using photoinduced force microscopy are used to show the morphology of the wood samples and the distribution of DOT on their surface. ICP-OES results show that the average DOT concentration in the wood samples is originally 0.8 and 1.5 wt% in the bulk and at the surface, respectively. Conditioning of the wood to a moisture content of 19% in a climatic chamber reduces DOT concentration by 8% for the fir and 17% for the spruce. After one week of contact with the clays, the results showed a rapid decrease of 25-40% in DOT concentration in wood. On longer periods (5 months), the spruce shows a tendency to reabsorb the DOT from the clay and the DOT migration stabilizes at 20%. These results contribute to defining the dosage of DOT when the wood is exposed to clay.