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1.
MethodsX ; 12: 102724, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38699467

RESUMO

In this study, a smartphone was used as the photometer for determination of iron (III) by forming a complex with thiocyanate. After color formation at concentrations of, image capture with mobile phone, signal analysis of each sample was performed by the application and converted to the absorption number. The calibration curve was completely linear in the range of 10 to 80 mg L-1 used and the linear coefficient was better than 0.9833. The limits of detection (LOD) and quantification (LOQ) were 0.1 and 0.3 mg L-1, respectively. Finally, this method was successfully used to measure iron in real samples.•A smartphone was used for the determination of iron (III), showcasing its potential in color compound analysis.•The method demonstrated superior performance in terms of calibration curve range and measurement speed compared to traditional atomic absorption devices.•The technique was successfully applied in the measurement of iron in real samples, indicating its practical applicability.

2.
MethodsX ; 12: 102616, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38379725

RESUMO

This paper introduces a novel, sensitive, and rapid method for the quantification of oxytetracycline, tetracycline, tilmicosin, and tylosin residues in cow's milk. The method involves a two-step process of extraction and detection. The extraction process uses acetonitrile and salting-out assisted liquid-liquid extraction to isolate the antibiotics from the milk. The detection process employs Liquid Chromatography coupled with photo-diode array detector (PDA) to quantify the antibiotics. The method has been successfully applied to milk samples, demonstrating its effectiveness and potential for widespread use in residue analysis.•The calibration curves for the antibiotics were found to be linear within the range of 0.06-3.0 µg/mL to 0.1-3.0 µg/mL.•The limits of detection for oxytetracycline, tetracycline, tilmicosin, and tylosin were 0.03 µg/mL, 0.02 µg/mL, 0.04 µg/mL, and 0.02 µg/mL respectively.•The method demonstrated an average recovery rate of over 90% from milk samples with peak values reaching up to 0.100-0.200 µg/mL.

3.
Bull Environ Contam Toxicol ; 112(1): 2, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38017139

RESUMO

2,2-Dibromo-3-nitrilopropionamide (DBNPA) is a widely used biocide with potential environmental implications due to its toxicity. This study aimed to investigate the in vivo toxicity of DBNPA in zebrafish (Danio rerio), a model organism in environmental toxicology. Both adult and larval zebrafish were exposed to varying concentrations of DBNPA, and significant morphological changes and mortality rates were observed. The study found that even relatively low concentrations of DBNPA can have detrimental effects on zebrafish embryonic development, and high concentrations resulted in rapid mortality in adult zebrafish and larvae. The LC50 values calculated from this study were 9.3 ppm for adults and 9.1 ppm for larvae, indicating the high toxicity of DBNPA to these organisms. These findings underscore the potential environmental impact of DBNPA and highlight the need for further research into its effects on aquatic ecosystems.


Assuntos
Desinfetantes , Poluentes Químicos da Água , Animais , Desinfetantes/toxicidade , Peixe-Zebra , Poluentes Químicos da Água/toxicidade , Larva , Ecossistema , Embrião não Mamífero
4.
MethodsX ; 11: 102431, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37867916

RESUMO

AIM: This study aimed to compare the elemental composition of traditional and flavored hookah tobacco, with a focus on heavy metals. METHODS: We used inductively coupled plasma mass spectrometry (ICP-MS) to analyze the concentrations of 29 elements in the raw tobacco, tobacco ash, hookah water after smoking, and tobacco smoke. RESULTS: The results showed that the traditional tobacco had significantly higher metal concentrations than the flavored tobacco in all samples. Most of the toxic metals (more than 98 %) remained in the smoke of both types of tobacco. The tobacco and hookah smoke contained high levels of harmful metals that can pose health risks to hookah users.•ICP-MS provides a comprehensive analysis of multiple elements simultaneously and it allows for precise quantification of metal concentrations in different samples.•ICP-MS requires specialized equipment and trained personnel and it may not detect elements present in extremely low concentrations.

5.
Environ Monit Assess ; 195(6): 761, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37249693

RESUMO

In this study, the degradation of two organophosphate pesticides, namely, propetamphos and azamethiphos, in the presence of Ag+ at different mole ratios was investigated. Moreover, the kinetic and degradation pathways of both chemicals in the range of 0-60 min were explored. Gas chromatography equipped with a thermionic specific detector was used to investigate the pesticide degradation kinetics and mechanism. The results show that the degradation rate of both pesticides follows first-order kinetic. The first-order rate constant and the half-life of reaction were in the range of 0.002-0.143 min-1, 187-2.1 min, and 0.005-0.164 min-1 and 60-1.8 min, for propetamphos and azamethiphos, respectively, at ambient temperature (25 ºC). Because group containing sulfur atom is a better leaving group than group containing nitrogen, the rate of degradation of azamethiphos is higher than propetamphos. In a higher mole ratio of Ag+ to pesticides, the degradation rate was increased, and it is possible to predict the rate of degradation of pesticides according to the chemical composition of leaving group.


Assuntos
Praguicidas , Prata , Monitoramento Ambiental
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