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1.
MethodsX ; 13: 102809, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39049929

RESUMEN

This research presents a novel method for measuring ethanol concentrations using a smartphone. The method involves an oxidation reaction with potassium dichromate and concentrated sulfuric acid, resulting in a green-blue color formation. The color intensity, corresponding to ethanol concentrations ranging from 0 to 100%, was captured using a smartphone camera within a specialized photography box. The images were then analyzed using a specific application, converting the color signal into an absorbance value. The calibration curve demonstrated excellent linearity in the range of 0-0.55 v/v % and its detection limit is 0.01 v/v%, with a correlation coefficient exceeding 0.995. The method was successfully applied to measure ethanol in real samples, including ordinary rose water and a bitter wheat drink.•The method is inexpensive.•The method is rapid.•The method is green.

2.
MethodsX ; 12: 102724, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38699467

RESUMEN

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.

3.
MethodsX ; 12: 102616, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38379725

RESUMEN

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.

4.
Bull Environ Contam Toxicol ; 112(1): 2, 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-38017139

RESUMEN

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.


Asunto(s)
Desinfectantes , Contaminantes Químicos del Agua , Animales , Desinfectantes/toxicidad , Pez Cebra , Contaminantes Químicos del Agua/toxicidad , Larva , Ecosistema , Embrión no Mamífero
5.
MethodsX ; 11: 102431, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37867916

RESUMEN

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.

6.
Environ Monit Assess ; 195(6): 761, 2023 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-37249693

RESUMEN

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.


Asunto(s)
Plaguicidas , Plata , Monitoreo del Ambiente
7.
Braz J Otorhinolaryngol ; 78(5): 64-8, 2012 Oct.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-23108822

RESUMEN

UNLABELLED: Squamous cell carcinoma (SCC) is the most common malignancy that involves the upper aerodigestive tract. Interleukin-13 (IL-13) is an immunoregulatory cytokine that has been reported to have some polymorphisms in it gene associated with same disease especially asthma and allergy. The present study aimed to investigate whether the polymorphisms of IL-13 gene (at positions of 1055C/T in the promoter of1L-13 gene and +2044G/T exon-4) differ in patients with head and neck SCC from healthy controls. METHODS: This study was investigated in patient with head and neck SCC (n = 137) and age- and sex-matched healthy controls (n = 127). Genotyping of IL-13 gene polymorphism was performed using polymerase chain reaction-based restriction fragment length polymorphism method. RESULTS: No statistically significant differences were found in the frequencies of genotypes and alleles between patients and control group at both sites (p = 0.16). In addition, no association was observed between investigated genotypes and other potential prognostic factors such as age, sex, primary tumor site, tumor size and smoking. CONCLUSION: This study suggests that there is no association between IL-13 gene polymorphisms (at position -1055C/T and +2044GI A) and susceptibility of the patients to SCC of head and neck.


Asunto(s)
Carcinoma de Células Escamosas/genética , Neoplasias de Cabeza y Cuello/genética , Interleucina-13/genética , Polimorfismo Genético , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Regiones Promotoras Genéticas/genética , Adulto Joven
8.
Braz. j. otorhinolaryngol. (Impr.) ; 78(5): 64-68, set.-out. 2012. tab
Artículo en Portugués | LILACS | ID: lil-654288

RESUMEN

O carcinoma espinocelular (CEC) é a neoplasia mais comum do trato aerodigestivo superior. A interleucina-13 (IL-13) é uma citocina imunorreguladora com polimorfismos relatados para seu gene associados com a mesma doença, especialmente asma e alergia. O presente estudo investigou se os polimorfismos do gene da IL-13 (posições 1055C/T no gene promotor da 1L-13 e +2044G/T exon 4) podem distinguir os pacientes com CEC de cabeça e pescoço de controles saudáveis. MÉTODO: O estudo analisou pacientes com CEC de cabeça e pescoço (n = 137) pareados por idade e sexo com um grupo de controles saudáveis (n = 127). A genotipagem do polimorfismo do gene da IL-13 foi executada pelo método de polimorfismo no comprimento de fragmentos de restrição baseado em reação em cadeia da polimerase. RESULTADOS: Não foram identificadas diferenças estatisticamente significativas nas frequências dos genótipos e alelos entre pacientes e controles em ambas as posições (p = 0,16). Além disso, não foi observada associação entre os genótipos investigados e outros fatores prognósticos, como idade, sexo, localização do tumor primário, tamanho do tumor e tabagismo. CONCLUSÃO: O presente estudo sugere que não há associação entre os polimorfismos do gene da IL-13 (nas posições -1055C/T e +2044GI A) e suscetibilidade dos pacientes a CEC de cabeça e pescoço.


Squamous cell carcinoma (SCC) is the most common malignancy that involves the upper aerodigestive tract. Interleukin-13 (IL-13) is an immunoregulatory cytokine that has been reported to have some polymorphisms in it gene associated with same disease especially asthma and allergy. The present study aimed to investigate whether the polymorphisms of IL-13 gene (at positions of 1055C/T in the promoter of1L-13 gene and +2044G/T exon-4) differ in patients with head and neck SCC from healthy controls. METHODS: This study was investigated in patient with head and neck SCC (n = 137) and age- and sex-matched healthy controls (n = 127). Genotyping of IL-13 gene polymorphism was performed using polymerase chain reaction-based restriction fragment length polymorphism method. RESULTS: No statistically significant differences were found in the frequencies of genotypes and alleles between patients and control group at both sites (p = 0.16). In addition, no association was observed between investigated genotypes and other potential prognostic factors such as age, sex, primary tumor site, tumor size and smoking. CONCLUSION: This study suggests that there is no association between IL-13 gene polymorphisms (at position -1055C/T and +2044GI A) and susceptibility of the patients to SCC of head and neck.


Asunto(s)
Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Carcinoma de Células Escamosas/genética , Neoplasias de Cabeza y Cuello/genética , /genética , Polimorfismo Genético , Estudios de Casos y Controles , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Genotipo , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Regiones Promotoras Genéticas/genética
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