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1.
Chemosphere ; 354: 141674, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38462186

RESUMO

This review critically examines the effectiveness of ion-imprinted membranes (IIMs) in selectively recovering lithium (Li) from challenging sources such as seawater and brine. These membranes feature customized binding sites that specifically target Li ions, enabling selective separation from other ions, thanks to cavities shaped with crown ether or calixarene for improved selectivity. The review thoroughly investigates the application of IIMs in Li extraction, covering extensive sections on 12-crown-4 ether (a fundamental crown ether for Li), its modifications, calixarenes, and other materials for creating imprinting sites. It evaluates these systems against several criteria, including the source solution's complexity, Li+ concentration, operational pH, selectivity, and membrane's ability for regeneration and repeated use. This evaluation places IIMs as a leading-edge technology for Li extraction, surpassing traditional methods like ion-sieves, particularly in high Mg2+/Li+ ratio brines. It also highlights the developmental challenges of IIMs, focusing on optimizing adsorption, maintaining selectivity across varied ionic solutions, and enhancing permselectivity. The review reveals that while the bulk of research is still exploratory, only a limited portion has progressed to detailed lab verification, indicating that the application of IIMs in Li+ recovery is still at an embryonic stage, with no instances of pilot-scale trials reported. This thorough review elucidates the potential of IIMs in Li recovery, cataloging advancements, pinpointing challenges, and suggesting directions for forthcoming research endeavors. This informative synthesis serves as a valuable resource for both the scientific community and industry professionals navigating this evolving field.


Assuntos
Éteres de Coroa , Éteres de Coroa/química , Lítio/química , Íons , Adsorção
2.
Biopreserv Biobank ; 20(6): 509-519, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34919454

RESUMO

Oxidative stress is a major contributory factor to cellular damage during semen cryopreservation and results in a decreased fertilizing capacity of cryopreserved bull sperm. The inclusion of exogenous antioxidants sometimes exerts deleterious effects on sperm quality. Thus, enhancing the endogenous production of antioxidants is a requirement. This study aimed to investigate the effect of milk type heated at different temperatures on the antioxidant potential of extenders, and the subsequent post-thaw quality parameters and in vivo fertility of buffalo bull semen. Cow (C) and buffalo whole milk (B) were used separately for semen extender preparation, heated at five different temperatures (T1 = 90°C, T2 = 100°C, T3 = 110°C, T4 = 120°C, T5 = 130°C) for 10 minutes. Reactive sulfhydryl groups were measured in each subgroup by Ellman's reagents as CT1 = 143.2 µM, CT2 = 147.4 µM, CT3 = 151.5 µM, CT4 = 157.2 µM, CT5 = 161.8 µM, BT1 = 168.3 µM, BT2 = 172.5 µM, BT3 = 176.7 µM, BT4 = 196.3 µM, and BT5 = 205.7 µM. All semen samples were cryopreserved in milk-based extenders by using standard procedures. Post-thaw quality parameters including total and progressive motility, mitochondrial membrane potential, plasma membrane integrity, and acrosome integrity were found to be higher (p < 0.05) in the group (BT3) containing buffalo milk heated at 110°C, whereas in the same group, lipid peroxidation was found to be lower (p < 0.05) as compared with other treatment groups and control group. In vivo fertility of cryopreserved buffalo sperm was compared among BT3, CT1 (conventionally used milk extender), and a Tris egg yolk extender group. The fertility rates [47% (54/114), 30% (33/108), and 36% (37/103)] were higher (p < 0.05) in BT3 as compared with other groups. This study suggests that buffalo milk heated at 110°C has high antioxidant potential and improves post-thaw quality and in vivo fertility of cryopreserved buffalo bull semen.


Assuntos
Búfalos , Preservação do Sêmen , Animais , Feminino , Bovinos , Masculino , Sêmen , Antioxidantes/farmacologia , Leite , Temperatura Alta , Análise do Sêmen , Motilidade dos Espermatozoides , Crioprotetores/farmacologia , Preservação do Sêmen/métodos , Espermatozoides , Criopreservação/métodos , Fertilidade
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