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1.
Bioresour Technol ; 388: 129708, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37625653

RESUMO

The rise of contaminants of emerging concern in water-resources due to human activities has driven research toward wastewater treatment, specifically adsorption. The utilization of woody biomass for biochar production in adsorption has shown promise due to its high availability. This study shows the preparation of magnetic biochars (MB) from waste black wattle sawdust, utilizing ZnCl2 and NiCl2 (proportions: 1:0.5:0.5 = MB-0.5 and 1:1:1 = MB-1) as activating and magnetic agents. Synthesized via microwave-assisted-pyrolysis, MB boasts a high surface area (up to 765 m2.g-1) and functional groups, enhancing metoprolol medicine adsorption. Nonlinear kinetic and isothermal models were tested; the Avrami fractional-order kinetic model and Liu's isothermal model provided the best fits for experimental data. Thermodynamics and spectroscopic studies revealed spontaneous and exothermic adsorption processes, with physisorption magnitude and dominance of hydrogen-bond and π-π-interactions. MB can be easily extracted from an aqueous medium using magnetic fields, while adsorption capacity could be regenerated through green solvent elution.

2.
Biosensors (Basel) ; 13(3)2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36979590

RESUMO

The COVID-19 pandemic has caused an unprecedented health and economic crisis, highlighting the importance of developing new molecular tools to monitor and detect SARS-CoV-2. Hence, this study proposed to employ the carrageenan extracted from Gigartina skottsbergii algae as a probe for SARS-CoV-2 virus binding capacity and potential use in molecular methods. G. skottsbergii specimens were collected in the Chilean subantarctic ecoregion, and the carrageenan was extracted -using a modified version of Webber's method-, characterized, and quantified. After 24 h of incubation with an inactivated viral suspension, the carrageenan's capacity to bind SARS-CoV-2 was tested. The probe-bound viral RNA was quantified using the reverse transcription and reverse transcription loop-mediated isothermal amplification (RT-LAMP) methods. Our findings showed that carrageenan extraction from seaweed has a similar spectrum to commercial carrageenan, achieving an excellent proportion of binding to SARS-CoV-2, with a yield of 8.3%. Viral RNA was also detected in the RT-LAMP assay. This study shows, for the first time, the binding capacity of carrageenan extracted from G. skottsbergii, which proved to be a low-cost and highly efficient method of binding to SARS-CoV-2 viral particles.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Carragenina/química , Sondas Moleculares , Pandemias , Técnicas de Diagnóstico Molecular/métodos , RNA Viral/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Sensibilidade e Especificidade
3.
Sci Justice ; 61(4): 378-383, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34172126

RESUMO

Latent fingermarks are important trace evidence found in crime scenes mainly used for identification purposes. Once deposited, the composition of samples changes over time influencing the efficacy of latent fingermark development methods. In this sense, the aims of this work were to characterize the fatty acid (FA) profile of sebaceous latent fingermarks by GC-FID and to preliminarily evaluate the development efficiency of enhancement methods (powder dusting, iodine fuming and silver nitrate method) in a 30-day period of aging under controlled parameters of temperature, photoperiod and humidity. Results showed that myristic (7.51 ± 0.76% - 13.39 ± 1.26%), palmitic (35.91 ± 1.07% - 40.81 ± 2.52%), stearic (6.67 ± 0.36% - 9.13 ± 0.36%) and oleic (18.08 ± 0.25% - 20.93 ± 0.26%) acid varied significantly (p < 0.05) over the 30-day period of analysis. Regarding development efficiency, fluorescent orange powder and the silver nitrate method also increased their efficacy to develop latent fingermarks over time while the iodine fuming method decreased its efficiency. Silver black powder had constant efficacy in the tested period. Changes in the constitution of sebaceous marks possibly influenced the development efficiency of enhancement techniques. This knowledge is important to better understand the kinetic of aging and its influence on the development method.


Assuntos
Iodo , Nitrato de Prata , Idoso , Corantes , Dermatoglifia , Humanos , Pós
4.
Drug Test Anal ; 12(9): 1264-1273, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32537903

RESUMO

Anabolic androgenic steroids (AASs) comprise a class of synthetic androgens resulting from chemical modifications of testosterone, known for their illicit consumption, which can result inextensive side effects. Extraction procedures applied to the analysis of their formulations are still limited to a few methodologies, despite the increasing numbers of confiscations of AASs. In this sense, the aims of this work were to evaluate the extraction of active ingredients from formulations of anabolic agents using solid-liquid or liquid-iquid, ultrasonic bath, ultrasonicprobe, and microwave-assisted extraction. The results indicated that the extraction procedures influenced the detected concentration of AASs, as the use of ultrasonic probe and microwave irradiation increased the overall extraction of anabolic agents compared with solid-liquid, liquid-liquid, and ultrasonic bath. Regarding oxymetholone, for instance, the microwave-assisted extraction and ultrasonic probe extracted, respectively, 37.46 ± 1.36 and 35.69 ± 0.98 mg/tablet, while solid-liquid extracted 29.63 ± 0.40 mg/tablet of the activeingredient. Therefore, alternative methods such as microwave-assisted extraction or theultrasonic probe could be used for the analysis of formulations of AASs assisting with the identification of illicit and toxic components.


Assuntos
Anabolizantes/análise , Fracionamento Químico/métodos , Congêneres da Testosterona/análise , Dopagem Esportivo , Extração Líquido-Líquido , Micro-Ondas , Extração em Fase Sólida , Comprimidos , Ultrassom/métodos
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