N-（2-Hydroxypropyl） methacrylamide copolymer-5-fluorouracil （PHPMA-FU） conjugates were synthesized by a novel and simplified synthetic route, and characterized by UV, FTIR and HPLC analyses. The conjugated content...N-（2-Hydroxypropyl） methacrylamide copolymer-5-fluorouracil （PHPMA-FU） conjugates were synthesized by a novel and simplified synthetic route, and characterized by UV, FTIR and HPLC analyses. The conjugated content of 5-fluorouracil （5-FU） was 3.41 ± 0.07 wt%. The stabilities of PHPMA-FU conjugates under different conditions were studied. The results showed that HPMA copolymer was a potential carrier for tumor-targeting delivery of 5-FU.展开更多
To develop new tumor targeting macromolecular conjugates,poly（HPMA）-SD-APMA-DTPA（HPMA：N-（2-hydroxypropyl）- methacrylamide;APMA：N-（3-ammopropyl）methacrylamide;DTPA：diethylenetriaminepentaacetic acid;SD：sulfa...To develop new tumor targeting macromolecular conjugates,poly（HPMA）-SD-APMA-DTPA（HPMA：N-（2-hydroxypropyl）- methacrylamide;APMA：N-（3-ammopropyl）methacrylamide;DTPA：diethylenetriaminepentaacetic acid;SD：sulfadiazine） was synthesized and characterized.The poly（HPMA）-SD-DTPA conjugates were radiolabeled with the radionuclide ^（99m）Tc and tested for uptake by cultured H22 cells in vitro.DTPA-^（99m）Tc（radiotracer 1） and poly（HPMA）-DTPA-^（99m）Tc（radiotracer 2） were also synthesized and characterized for comparison.The uptake of poly（HPMA）-SD-DTPA-^（99m）Tc（radiotracer 3,34.76%） was significantly higher than that of poly（HPMA）-DTPA-^（99m）Tc（16.40%）,indicating that uptake of the poly（HPMA）-SD-DTPA-^（99m）T was active binding.The uptake of poly（HPMA）-DTPA-^（99m）Tc was significantly higher than that of DTPA-^（99m）Tc（2.98%）, suggesting that uptake of the poly（HPMA）-DTPA-^（99m）T was passive binding.The data suggest that the poly（HPMA）-SDAPMA -DTPA conjugates might be useful as tumor targeting macromolecular conjugates.展开更多
Aluminum nitride(AlN)is considered one of the most desirable materials for integrated circuits and electronic packaging substrates.However,raw AlN powder reacts easily with water,forming Al(OH)3 or AlOOH on the surfac...Aluminum nitride(AlN)is considered one of the most desirable materials for integrated circuits and electronic packaging substrates.However,raw AlN powder reacts easily with water,forming Al(OH)3 or AlOOH on the surface and hindering the development of an aqueous tape-casting process for preparing AlN ceramic substrates.In this study,hydrolyzed polymaleic anhydride(HPMA)was used to modify AlN powder,which has good water solubility and dispersibility.The AlN powder was modified with 5 wt%HPMA remained stable in water for at least 90 h under magnetic stirring condition and 24 h under ball milling condition,indicating that HPMA-modified AlN powder has good resistance to hydrolysis.The action mechanism of HPMA is revealed.Firstly,–COOH of the HPMA polymer and the oxide layer on the surface of the AlN powder underwent a dehydration condensation reaction to form a compound.Secondly,long chains of the polymer further coated the surface of the AlN powder,forming an anti-hydration layer with a thickness of about 7.0 nm on the surface of the AlN particles.In addition,AlN green sheets were successfully prepared by aqueous tape casting using the HPMA-modified AlN powder without additional dispersants.Subsequently,AlN ceramic substrates were obtained by sintering at 1750℃for 4 h under an N2 atmosphere with a pressure of 0.2 MPa.The relative density and thermal conductivity were tested to be 97.3%and 122 W/(m·K),respectively.展开更多
基金supported by the National Natural Science Foundation of China(No.30500636)Ministry of Education(NCET-06-0786).
文摘N-（2-Hydroxypropyl） methacrylamide copolymer-5-fluorouracil （PHPMA-FU） conjugates were synthesized by a novel and simplified synthetic route, and characterized by UV, FTIR and HPLC analyses. The conjugated content of 5-fluorouracil （5-FU） was 3.41 ± 0.07 wt%. The stabilities of PHPMA-FU conjugates under different conditions were studied. The results showed that HPMA copolymer was a potential carrier for tumor-targeting delivery of 5-FU.
基金the National Natural Science Foundation of China(No.20964003)for funding
文摘To develop new tumor targeting macromolecular conjugates,poly（HPMA）-SD-APMA-DTPA（HPMA：N-（2-hydroxypropyl）- methacrylamide;APMA：N-（3-ammopropyl）methacrylamide;DTPA：diethylenetriaminepentaacetic acid;SD：sulfadiazine） was synthesized and characterized.The poly（HPMA）-SD-DTPA conjugates were radiolabeled with the radionuclide ^（99m）Tc and tested for uptake by cultured H22 cells in vitro.DTPA-^（99m）Tc（radiotracer 1） and poly（HPMA）-DTPA-^（99m）Tc（radiotracer 2） were also synthesized and characterized for comparison.The uptake of poly（HPMA）-SD-DTPA-^（99m）Tc（radiotracer 3,34.76%） was significantly higher than that of poly（HPMA）-DTPA-^（99m）Tc（16.40%）,indicating that uptake of the poly（HPMA）-SD-DTPA-^（99m）T was active binding.The uptake of poly（HPMA）-DTPA-^（99m）Tc was significantly higher than that of DTPA-^（99m）Tc（2.98%）, suggesting that uptake of the poly（HPMA）-DTPA-^（99m）T was passive binding.The data suggest that the poly（HPMA）-SDAPMA -DTPA conjugates might be useful as tumor targeting macromolecular conjugates.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.52102101,52267001)the Natural Science Foundation of Jiangxi Province(No.20212BAB204019).
文摘Aluminum nitride(AlN)is considered one of the most desirable materials for integrated circuits and electronic packaging substrates.However,raw AlN powder reacts easily with water,forming Al(OH)3 or AlOOH on the surface and hindering the development of an aqueous tape-casting process for preparing AlN ceramic substrates.In this study,hydrolyzed polymaleic anhydride(HPMA)was used to modify AlN powder,which has good water solubility and dispersibility.The AlN powder was modified with 5 wt%HPMA remained stable in water for at least 90 h under magnetic stirring condition and 24 h under ball milling condition,indicating that HPMA-modified AlN powder has good resistance to hydrolysis.The action mechanism of HPMA is revealed.Firstly,–COOH of the HPMA polymer and the oxide layer on the surface of the AlN powder underwent a dehydration condensation reaction to form a compound.Secondly,long chains of the polymer further coated the surface of the AlN powder,forming an anti-hydration layer with a thickness of about 7.0 nm on the surface of the AlN particles.In addition,AlN green sheets were successfully prepared by aqueous tape casting using the HPMA-modified AlN powder without additional dispersants.Subsequently,AlN ceramic substrates were obtained by sintering at 1750℃for 4 h under an N2 atmosphere with a pressure of 0.2 MPa.The relative density and thermal conductivity were tested to be 97.3%and 122 W/(m·K),respectively.
