RESUMO
Trace analysis of lipophilic substances in complex environmental, food, or biological matrices has proven to be a challenge, on account of their high susceptibility to adsorption by particulate matter and liquid-solid interfaces. For this purpose, liquid-liquid extraction (LLE) is often employed as the separation method, which uses water-immiscible organic solvents. As an alternative, magnetic solid-phase extraction (MSPE) allows for adsorption, separation, and recovery of analytes from large volumes of aqueous samples with minimum usage of organic solvents. However, the poor selectivity hampers its performance in various scenarios, especially in sewage samples where complicated and unpredictable interference exists, resulting in block of the active adsorption sites of the sorbent. To this end, we propose receptor-affinity MSPE employing magnetic liposomes decorated with cell membranes expressing G-protein-coupled receptor as the sorbents. Application of the novel sorbent CM@Lip@Fe infused with CB1 cannabinoid receptors was demonstrated for the targeted extraction and enrichment of tetrahydrocannabinol from sewage matrix. Thanks to the high affinity and molecular selectivity of the ligand-receptor interactions, a limit of quantitation of 5.17 ng/L was achieved coupled with HPLC-MS/MS in unfiltered raw sewage, featuring minimum usage of organic solvents, fivefold enhanced sensitivity, low sorbent dosage (75 mg/L of sewage), and high efficiency as major advantages over conventional LLE. This work establishes a framework for efficient separation of specific molecules from complex media, thus promising to extend and refine standard LLE as the clean-up procedure for trace analysis.
Assuntos
Lipossomos , Esgotos , Espectrometria de Massas em Tandem/métodos , Solventes , Extração em Fase Sólida/métodos , Água , Membrana Celular , Fenômenos Magnéticos , Cromatografia Líquida de Alta Pressão/métodosRESUMO
A large number of cases showed that fentanyl (FEN) has become the main cause of death from illegal drug overdose owing to its potent effect on respiratory depression, which has emerged as a grave threat to public health and safety. However, traditional analytical methods require cost-prohibitive equipment, complex pretreatment procedures, and technically trained experts, thus highlighting the urgent need to develop a cost-effective, straightforward, and highly sensitive method to detect FEN. This work demonstrated a dual-readout sensor FGGC-AuNCs@Q7 for FEN detection, which is based on the molecular recognition and self-assembly between the macrocycle cucurbit[7]uril (Q7) and FEN, accompanying spontaneous visual Tyndall effect and fluorescence optical responses of the gold nanoclusters within seconds. A detection limit of 1 ng mL-1 and a linear range of 9 to 148 000 ng mL-1 were achieved for fluorescence detection on FEN, with favorable selectivity in the presence of other illicit drugs or common interferents. The proposed method has been proved by its satisfactory application for the analysis of human urine.
Assuntos
Ouro , Nanopartículas Metálicas , Humanos , Limite de Detecção , Espectrometria de FluorescênciaRESUMO
The disturbance characteristics and driving factors of human activity intensity in national parks are important factors affecting environmental change in ecological function areas. In-depth analysis of these must be the basis of improving the ecological environment in northwest China. This study selected data related to human activities from 2000 to 2020 to analyze the comprehensive impact of human interference on national park development and found that the NDVI (Normalized Difference Vegetation Index) of Qilian Mountain National Park showed an increasing trend and that the NPP (net primary productivity) showed spatial distribution characteristics of decreasing from east to west during the study period. This showed that human interference in and around the national park was changing significantly and that the high value area was gradually shifting southward. In the first decade, economic and social development was slow; related industries such as industry, tourism, and modern agriculture were not introduced on a large scale; and the ecological environment was in relatively good condition, with relatively weak human interference. However, in the second decade, human interference was prominent, with deeper ecological damage, but rapid economic development. Infrastructure development, population urbanization, and traditional production and living practices were the main factors driving changes in human interference. The Chinese government's proposed green building policy will further reduce the ecological impact of human activities while ensuring economic development. Building upon this, the present paper puts forth a "zero-disturbance" framework for national parks, aiming to offer recommendations for the future development of such parks.
Assuntos
Ecossistema , Parques Recreativos , Humanos , Monitoramento Ambiental , Conservação dos Recursos Naturais , ChinaRESUMO
The Jiangmen Underground Neutrino Observatory (JUNO) is a 20 kt low level radioactivity liquid scintillator detector in a laboratory 650 m underground. An excellent energy resolution and a large volume offer exciting opportunities for addressing many important topics in neutrino physics. High purity nitrogen is an important factor to ensure the low background of the JUNO detector. High Purity Nitrogen (HPN) is used for detector purging, pipe cleaning, and scintillator purification, among other things in JUNO. According to JUNO's requirements, the radon concentration in HPN should be less than 10 µBq/m3. To meet this requirement, A high-purity nitrogen plant with 100 Nm3/h maximum rate was designed and constructed. Low-temperature adsorption technology is used to remove radioactive impurities in nitrogen. High purification efficiency was ensured by using an activated carbon column with high column height-to-diameter ratio. Electrostatic collection and low-temperature enrichment methods are combined to measure radon in nitrogen. After ten days of continuous operation at 50 Nm3/h flux rate, the plant can to reduce the radon concentration in nitrogen from 37.4±1.8µBq/m3 to less than 1.33 µBq/m3. After HPN with flow rate of 50 Nm3/h passing through low-background pipeline (About 1.3 km), the radon concentration of HPN is 5.6±0.6µBq/m3.
RESUMO
Ammonia stress in aquaculture systems poses a great threat to the growth and survival of the Pacific whiteleg shrimp Litopenaeus vannamei. Although the ammonia stress tolerance capacity of L. vannamei has been found to vary significantly among different breeding families, the underneath mechanisms are still largely unknown. In this study, the ammonia tolerance capacity of different L. vannamei breeding families was compared. Results confirmed the significant differences in the ammonia adaptability among different families. To ascertain the underlying adaptive strategies, ATP status, ATP synthase activity, expression and activities of ammonia excretion and metabolism-related enzymes, and apoptosis in shrimp gills were analyzed. Furthermore, transcriptomic analyses were also performed to elucidate the molecular mechanisms. Our results indicated that ammonia-tolerant L. vannamei may possess (1) enhanced ability to excrete ammonia, (2) better capacity to convert ammonia into less toxic products, and (3) sufficient energy reserves for ammonia-compensating processes.
Assuntos
Penaeidae , Poluentes Químicos da Água , Humanos , Animais , Estresse Fisiológico , Amônia/toxicidade , Poluentes Químicos da Água/toxicidade , Perfilação da Expressão Gênica , Penaeidae/genética , Trifosfato de AdenosinaRESUMO
Information regarding the metabolism of illicit drugs is under urgent need for toxicological assessment. Its development, however, is limited by the currently available animal models. To this end, we proposed three-dimensional (3D) HepaRG spheroids as an in vitro model to study the effects of illicit drugs on hepatic cytochrome P450 (CYP450) enzymes and potential drug-drug interactions (DDIs). By comparing the results from animal and cell experiments, we confirmed the significant impact of heroin, morphine, tetrahydrocannabinol, and fentanyl on CYP450 enzymes, and the 3D spheroids results were in good agreement with the animal results for 2B6, 2C19, 2D6. Using 3D HepaRG spheroids, we demonstrated DDIs between heroin as a 2B6 perpetrator and clinical medicine for cancer, depression, and illicit drug withdrawal. Specifically, the clearance rate of 5.4 µM bupropion was increased by 214 % under DDI with 5 µM heroin, highlighting the importance of DDI pre-screening and individualized medication guidance for illicit drug users. This research contributes to the growing body of evidence regarding the metabolic toxicity of illicit drugs and suggests 3D HepaRG spheroids as a high-throughput and cost-efficient platform for DDI analysis.
Assuntos
Drogas Ilícitas , Animais , Sistema Enzimático do Citocromo P-450/metabolismo , Interações Medicamentosas , Heroína/metabolismo , Heroína/farmacologia , Drogas Ilícitas/metabolismo , Drogas Ilícitas/toxicidade , FígadoRESUMO
OBJECTIVE: To identify Paragonimus harinasutai from Ninghai, Zhejiang Province, China. METHODS: Metacercariae were collected from the crabs Sinopotamon chekiangenes in Xixi village of Ninghai County for ITS2 sequence analysis, CO1 sequence analysis and endonuclease BsaHI and StuI analysis by PCR-RFLP. Results The fingerprintings of PCR-RFLP were virtually same to the isolate from Thailand (Nakorn-nayok). The ITS2 sequence with 366 bp and CO1 sequence with 390 bp of the metacercariae collected from Ninghai revealed a nucleotide identity 95.6% and 89.5% respectively to the Thai isolate. CONCLUSION: The study confirmed that Paragonimus harinasutai is present in Ninghai, China, with certain variation on molecular biology in comparison to the Thai isolate.