To obtain expected rapid-release and sustained-release of ketoprofen gel beads, this paper adopted biopolymer alginate to prepare alginate beads and chitosan-alginate gel beads. Formulation factors were investigated a...To obtain expected rapid-release and sustained-release of ketoprofen gel beads, this paper adopted biopolymer alginate to prepare alginate beads and chitosan-alginate gel beads. Formulation factors were investigated and optimized by the single factor test. The release of ketoprofen from calcium alginate gel beads in pH 1.0 hydrochloric acid solution was less than 10% during 2 h, then in pH6.8 was about 95% during 45 min, which met the requirements of rapid-release preparations. However, the drug release of chitosan-alginate gel beads in pH1.0 was less than 5% during 2 h, then in pH6.8 was about 50% during 6 h and reached more than 95% during 12 h, which had a good sustained-release behavior. In addition, the release kinetics of keteprofen from the calcium alginate gel beads fitted well with the Korsmeyer–Peppas model and followed a case-II transport mechanism. However, the release of keteprofen from the chitosan-alginate gel beads exhibited a non-Fickian mechanism and based on the mixed mechanisms of diffusion and polymer relaxation from chitosanalginate beads. In a word, alginate gel beads of ketoprofen were instant analgesic, while chitosan-alginate gel beads could control the release of ketoprofen during gastrointestinal tract and prolong the drug's action time.展开更多
The first attempt of constructing supramolecular prodrug micelles based on the host-guest interaction between water-soluble pillar[6]arene(WP6)and a novel doxorubicin(DOX)-based drug-drug conjugate(G)is reported,in wh...The first attempt of constructing supramolecular prodrug micelles based on the host-guest interaction between water-soluble pillar[6]arene(WP6)and a novel doxorubicin(DOX)-based drug-drug conjugate(G)is reported,in which the drug-drug conjugate is synthesized by conjugating anticancer drug DOX with another drug isoniazide via the acid-cleavable hydrazone bond.The obtained WP6⊃G micelles are stable under physiological conditions,whereas the cumulative release of DOX is approximate to 100%within 30 min at pH 5.5 by simulating the endo-lysosomal environment at 37℃.Therefore,this WP6-based prodrug micelles can achieve efficient DOX ac-cumulation in the acidic tumor cells within a short period of time,which is very important and valuable;meanwhile it can also reduce the unexpected premature burst release under physiological condition.Furthermore,cellular in-ternalization and localization experiments demonstrated that these prodrug micelles enter cancer cells mainly via endocytosis and can lead to significant drug accumulation in SKOV3 cancer cells,implying its promising future for cancer therapy.展开更多
Objective:This paper aims to establish a simple and practical method for the rapid detection of ammonia nitrogen in water on the spot,and to transmit the detection results to the Internet via GSM network,and to publis...Objective:This paper aims to establish a simple and practical method for the rapid detection of ammonia nitrogen in water on the spot,and to transmit the detection results to the Internet via GSM network,and to publish and update them in real time.Methods:Phenol salt colorimetry was used to measure the absorbance value of indigo phenol blue,the product of the reaction between ammonia nitrogen and phenol salt in water samples,using sodium nitrosoferricyanide sodium hydroxide as catalyst and a microphotoelectric colorimetric instrument developed by ourselves,or a simple visual colorimetric semi-quantitative method was used to measure the ammonia nitrogen content in water samples.Then,the general GSM wireless communication module built in the microphotoelectric colorimeter was used to realize the remote transmission of the test result data and the real-time update and release on the Internet.Results:The results of this method showed that the correlation of the method was significant,and the precision and accuracy were similar to the national standard Nessler's reagent spectrophotometry.The relative standard deviation is 4.4%,and the relative error is 2.7%.In 5-10 min,the detection of ammonia and nitrogen in single water sample can be completed on site,and the results can be released.For quantitative and semi-quantitative detection,the lowest detection concentrations are 0.05 mg/L and 0.2 mg/L,respectively,which are basically free from the interference of pH and common ions.In the coverage area of GSM network,the wireless transmission of data results was unobstructed and delayed,and the effect was satisfactory.Conclusion:The method is simple,rapid,practical and reliable,which is suitable for the field rapid determination of ammonia nitrogen in water,and the real-time remote transmission of the detection results.It provides a high-efficiency,low-cost and simple technical means for the field water quality monitoring and the rapid acquisition of water quality data.展开更多
The study discussed the rapid method to test and predict the longevity of controlled release fertilizers （CRFs） coated by water soluble resin by using the short-term leaching under higher temperature. Pure water dis...The study discussed the rapid method to test and predict the longevity of controlled release fertilizers （CRFs） coated by water soluble resin by using the short-term leaching under higher temperature. Pure water dissolving incubation and higher temperature leaching were used to study the patterns of the nutrient release of the CRFs. The correlation analysis between the days at 25℃ and the hours at 80℃ of Trincote 1 and Trincote 2 for the same cumulative release rates were conducted. Patterns of cumulative nutrient release curve followed one factor quadratic regression equation at each given temperatures, and each of relative coefficient was bigger than 0.995. As the temperature increased, nutrients release of the CRFs increased. The longevity of resin coated CRFs were predicted by use of both the cumulative nutrients release equation at 80℃ and the regression equation of release time needed for the same cumulative release rates between 25 and 80℃. There were only 0.3-6.9% relative errors between the tested longevity and predicted one. In conclusion, the longevity of resin coated CRFs could be predicted more quickly and precisely by use of the higher temperature short-term leaching method than that of the traditional differential release rate. The longevity of resin coated CRF could be rapidly and precisely predicted in a few hours by application of the higher temperature shortterm leaching method.展开更多
基金supported by the program of supporting career development of young and middle-aged teachers from Shenyang Pharmaceutical University (ZQN2015011)the Open fund of Key Laboratory of Ministry of Education for TCM Viscera-State Theory and Applications, Liaoning University of Traditional Chinese Medicine(zyzx1608)
文摘To obtain expected rapid-release and sustained-release of ketoprofen gel beads, this paper adopted biopolymer alginate to prepare alginate beads and chitosan-alginate gel beads. Formulation factors were investigated and optimized by the single factor test. The release of ketoprofen from calcium alginate gel beads in pH 1.0 hydrochloric acid solution was less than 10% during 2 h, then in pH6.8 was about 95% during 45 min, which met the requirements of rapid-release preparations. However, the drug release of chitosan-alginate gel beads in pH1.0 was less than 5% during 2 h, then in pH6.8 was about 50% during 6 h and reached more than 95% during 12 h, which had a good sustained-release behavior. In addition, the release kinetics of keteprofen from the calcium alginate gel beads fitted well with the Korsmeyer–Peppas model and followed a case-II transport mechanism. However, the release of keteprofen from the chitosan-alginate gel beads exhibited a non-Fickian mechanism and based on the mixed mechanisms of diffusion and polymer relaxation from chitosanalginate beads. In a word, alginate gel beads of ketoprofen were instant analgesic, while chitosan-alginate gel beads could control the release of ketoprofen during gastrointestinal tract and prolong the drug's action time.
基金supported by the National Natural Science Foundation of China(Nos.91227106,21202083)the National Science Foundation of Jiangsu(No.BK20140595).
文摘The first attempt of constructing supramolecular prodrug micelles based on the host-guest interaction between water-soluble pillar[6]arene(WP6)and a novel doxorubicin(DOX)-based drug-drug conjugate(G)is reported,in which the drug-drug conjugate is synthesized by conjugating anticancer drug DOX with another drug isoniazide via the acid-cleavable hydrazone bond.The obtained WP6⊃G micelles are stable under physiological conditions,whereas the cumulative release of DOX is approximate to 100%within 30 min at pH 5.5 by simulating the endo-lysosomal environment at 37℃.Therefore,this WP6-based prodrug micelles can achieve efficient DOX ac-cumulation in the acidic tumor cells within a short period of time,which is very important and valuable;meanwhile it can also reduce the unexpected premature burst release under physiological condition.Furthermore,cellular in-ternalization and localization experiments demonstrated that these prodrug micelles enter cancer cells mainly via endocytosis and can lead to significant drug accumulation in SKOV3 cancer cells,implying its promising future for cancer therapy.
文摘Objective:This paper aims to establish a simple and practical method for the rapid detection of ammonia nitrogen in water on the spot,and to transmit the detection results to the Internet via GSM network,and to publish and update them in real time.Methods:Phenol salt colorimetry was used to measure the absorbance value of indigo phenol blue,the product of the reaction between ammonia nitrogen and phenol salt in water samples,using sodium nitrosoferricyanide sodium hydroxide as catalyst and a microphotoelectric colorimetric instrument developed by ourselves,or a simple visual colorimetric semi-quantitative method was used to measure the ammonia nitrogen content in water samples.Then,the general GSM wireless communication module built in the microphotoelectric colorimeter was used to realize the remote transmission of the test result data and the real-time update and release on the Internet.Results:The results of this method showed that the correlation of the method was significant,and the precision and accuracy were similar to the national standard Nessler's reagent spectrophotometry.The relative standard deviation is 4.4%,and the relative error is 2.7%.In 5-10 min,the detection of ammonia and nitrogen in single water sample can be completed on site,and the results can be released.For quantitative and semi-quantitative detection,the lowest detection concentrations are 0.05 mg/L and 0.2 mg/L,respectively,which are basically free from the interference of pH and common ions.In the coverage area of GSM network,the wireless transmission of data results was unobstructed and delayed,and the effect was satisfactory.Conclusion:The method is simple,rapid,practical and reliable,which is suitable for the field rapid determination of ammonia nitrogen in water,and the real-time remote transmission of the detection results.It provides a high-efficiency,low-cost and simple technical means for the field water quality monitoring and the rapid acquisition of water quality data.
基金the National Key Technologies R&D Program during the 11th Five-Year Plan period of China (2006BAD10B02)the National Natural Science Foundation of China (39870433,30270769)
文摘The study discussed the rapid method to test and predict the longevity of controlled release fertilizers （CRFs） coated by water soluble resin by using the short-term leaching under higher temperature. Pure water dissolving incubation and higher temperature leaching were used to study the patterns of the nutrient release of the CRFs. The correlation analysis between the days at 25℃ and the hours at 80℃ of Trincote 1 and Trincote 2 for the same cumulative release rates were conducted. Patterns of cumulative nutrient release curve followed one factor quadratic regression equation at each given temperatures, and each of relative coefficient was bigger than 0.995. As the temperature increased, nutrients release of the CRFs increased. The longevity of resin coated CRFs were predicted by use of both the cumulative nutrients release equation at 80℃ and the regression equation of release time needed for the same cumulative release rates between 25 and 80℃. There were only 0.3-6.9% relative errors between the tested longevity and predicted one. In conclusion, the longevity of resin coated CRFs could be predicted more quickly and precisely by use of the higher temperature short-term leaching method than that of the traditional differential release rate. The longevity of resin coated CRF could be rapidly and precisely predicted in a few hours by application of the higher temperature shortterm leaching method.
