Cryogels are gel matrices that have interconnected macropores and are formed in freezing-thawing systems. These interconnected macropores give elasticity to cryogels. Transdermal controlled-release systems can be used...Cryogels are gel matrices that have interconnected macropores and are formed in freezing-thawing systems. These interconnected macropores give elasticity to cryogels. Transdermal controlled-release systems can be used to deliver drugs with short biological half-life and can maintain plasma levels of very potent drugs within a narrow therapeutic range for prolonged periods. In this study, cryogels have been used in a different area--transdermal controlled-release system, to obtain controlled drug release medium. For this purpose, naproxen sodium has been selected as a model drug. Naproxen, a propionic acid derivative, is a NSAID （nonsteroidal anti-inflammatory drug）. For controlled releasing of naproxen sodium, cryogels that have naproxen sodium in macropores have been prepared in sheet form for local application. Acrylamide based cryogel bands have been synthesized by flee radical cryogelation process. These cryogel bands have different pore size and includes naproxen sodium in their pores. This cryogel material has been characterized by swelling tests and SEM. Then, releasing ofnaproxen sodium from cryogels has been investigated at two different pH values, 7.4 and 5.5. According to experimental data, it has seen that these cryogel matrices that including naproxen sodium in macropores could be used in controlled drug releasing systems as bandages or other transdermal controlled releasing agents at room temperature展开更多
This study demonstrates the preparation and characterization of a novel ion imprinted cryogel which exhibits high affinity and selectivity towards Ce（Ⅲ） ions in aqueous solutions and bastnasite ore samples.2-Hydrox...This study demonstrates the preparation and characterization of a novel ion imprinted cryogel which exhibits high affinity and selectivity towards Ce（Ⅲ） ions in aqueous solutions and bastnasite ore samples.2-Hydroxyethyl methacrylate（HEMA） and N-methacryloylamido antipyrine（MAAP） were used as functional monomers for the preparation of Ce（Ⅲ） imprinted cryogel. The effects of various factors such as initial Ce（Ⅲ） concentration, flow rate, pH, interaction time and ionic strength on the Ce（Ⅲ） binding to the prepared ion imprinted cryogels were also studied. The binding equilibrium for Ce（Ⅲ） is obtained in30 min at the flow rate of 0.5 mL/min. The maximum binding capacity of the prepared ion imprinted cryogel towards Ce（Ⅲ） is obtained as 36.58 mg/g at optimum conditions. The selectivity of the prepared ion imprinted cryogel towards Ce（Ⅲ） in the presence of other possible interfering lanthanide ions such as La（Ⅲ） and Nd（Ⅲ） were also performed. The obtained results showed that the prepared ion imprinted cryogel exhibits high selectivity and sensitivity towards Ce（Ⅲ） ions. The limit of detection（LOD） was found as 50 μg/L.展开更多
文摘Cryogels are gel matrices that have interconnected macropores and are formed in freezing-thawing systems. These interconnected macropores give elasticity to cryogels. Transdermal controlled-release systems can be used to deliver drugs with short biological half-life and can maintain plasma levels of very potent drugs within a narrow therapeutic range for prolonged periods. In this study, cryogels have been used in a different area--transdermal controlled-release system, to obtain controlled drug release medium. For this purpose, naproxen sodium has been selected as a model drug. Naproxen, a propionic acid derivative, is a NSAID （nonsteroidal anti-inflammatory drug）. For controlled releasing of naproxen sodium, cryogels that have naproxen sodium in macropores have been prepared in sheet form for local application. Acrylamide based cryogel bands have been synthesized by flee radical cryogelation process. These cryogel bands have different pore size and includes naproxen sodium in their pores. This cryogel material has been characterized by swelling tests and SEM. Then, releasing ofnaproxen sodium from cryogels has been investigated at two different pH values, 7.4 and 5.5. According to experimental data, it has seen that these cryogel matrices that including naproxen sodium in macropores could be used in controlled drug releasing systems as bandages or other transdermal controlled releasing agents at room temperature
文摘This study demonstrates the preparation and characterization of a novel ion imprinted cryogel which exhibits high affinity and selectivity towards Ce（Ⅲ） ions in aqueous solutions and bastnasite ore samples.2-Hydroxyethyl methacrylate（HEMA） and N-methacryloylamido antipyrine（MAAP） were used as functional monomers for the preparation of Ce（Ⅲ） imprinted cryogel. The effects of various factors such as initial Ce（Ⅲ） concentration, flow rate, pH, interaction time and ionic strength on the Ce（Ⅲ） binding to the prepared ion imprinted cryogels were also studied. The binding equilibrium for Ce（Ⅲ） is obtained in30 min at the flow rate of 0.5 mL/min. The maximum binding capacity of the prepared ion imprinted cryogel towards Ce（Ⅲ） is obtained as 36.58 mg/g at optimum conditions. The selectivity of the prepared ion imprinted cryogel towards Ce（Ⅲ） in the presence of other possible interfering lanthanide ions such as La（Ⅲ） and Nd（Ⅲ） were also performed. The obtained results showed that the prepared ion imprinted cryogel exhibits high selectivity and sensitivity towards Ce（Ⅲ） ions. The limit of detection（LOD） was found as 50 μg/L.
