Nifedipine(NF),a widely prescribed antihypertensive agent,necessitates long-term administration to maintain therapeutic efficacy.Although osmotic pump formulations,such as Bayer’s Adalat^(®),are well-established...Nifedipine(NF),a widely prescribed antihypertensive agent,necessitates long-term administration to maintain therapeutic efficacy.Although osmotic pump formulations,such as Bayer’s Adalat^(®),are well-established for achieving zero-order drug release,their complex manufacturing requirements significantly elevate production costs.In this study,we employed mesoporous silica as a drug carrier for nifedipine and incorporated it with an organic polymer matrix to construct an organic-inorganic hybrid nanocomposite(OIN).This nanostructured system demonstrated robust sustained-release properties in both in vitro and in vivo evaluations,with the in vitro release profile exhibiting classical first-order kinetics.To further optimize the release behavior,we combined OIN with conventional tablet-forming techniques to create an oral nanocomposite system(ONS)capable of achieving near-zero-order release.Remarkably,the cumulative release profiles of ONS closely mirrored those of the commercially available Adalat^(®)osmotic formulation across multiple time points.Moreover,we conducted a theoretical analysis of the release mechanisms underlying both OIN and ONS systems,offering novel mechanistic insights that could inform the future design of advanced sustained-release drug delivery platforms.展开更多
The fertiliser industry faces a continuing challenge to improve the efficiency of their products,particularly of nitrogenous fertilisers,and to minimise adverse impacts.Therefore,a new slow release fertilizer,ureaimpr...The fertiliser industry faces a continuing challenge to improve the efficiency of their products,particularly of nitrogenous fertilisers,and to minimise adverse impacts.Therefore,a new slow release fertilizer,ureaimpregnated woodchips from tropical plant biomass(oil palm frond and rubberwood),was developed.The morphology of the impregnated woodchips was investigated by scanning electron microscopy and the success of impregnation of urea and nitrogen deposition into the woodchips was confirmed by energy dispersive X-ray spectrometry.When nitrogen release patterns from impregnated woodchips fertiliser were simulated using a soil solution and distilled water as leaching solutions in a static condition for 768 h,release was slow and steady,although the release rate was lower in distilled water than in the soil solution.展开更多
Supramolecular hydrogels demonstrate considerable potential in drug delivery owing to their distinctive features,including bio-adhesiveness,self-healing behaviors,biodegradability,and biocompatibility.Nevertheless,the...Supramolecular hydrogels demonstrate considerable potential in drug delivery owing to their distinctive features,including bio-adhesiveness,self-healing behaviors,biodegradability,and biocompatibility.Nevertheless,the fabrication of supramolecular hydrogels utilizing exclusively clinically approved drugs remain challenging,typically necessitating chemical modifications of the drugs to facilitate the gelation process.In this study,we report a novel type of supramolecular hydrogel through the direct assembly of two clinically approved drugs,tobramycin and mycophenolic acid,via combined electrostatic and hydrophobic interactions.The hydrogel shows adjustable bio-adhesiveness,zero-order release kinetics,good biocompatibility,and maintained antibacterial and immunosuppressive activities.It efficiently inhibits bacterial infections and foreign body responses,and accelerates tissue healing in several subcutaneous/intraosseous implantation models accompanied by bacteria infections.This work provides a facile and promising strategy to fabricate supramolecular hydrogels with stable drug release kinetics using clinically approved drugs.展开更多
The release technique,affecting the survival rate of fish species released for stock enhancement,plays a vital role in the effectiveness of the enhancement.In order to improve the probability of released fish settling...The release technique,affecting the survival rate of fish species released for stock enhancement,plays a vital role in the effectiveness of the enhancement.In order to improve the probability of released fish settling down to bottom,a new cage-based release technique was designed and tested via a water tank with artificial reef models.Two coral reef fish species,Sebastes schlegelii and Paralichthys olivaceus were assessed using this technique.Fish behavior and distribution in water tank were recorded and compared with the traditional release release techniques.Results showed that in the case of cage-based release technique:1)when the release process is just finished,the distribution index(DI)of juveniles S.schlegelii and P.olivaceus were 97.8%and 98.9%at reef area,40%and 71.1%at release point,respectively,which was higher than those using two alternative techniques;2)its impact duration was less than that in the other two conditions,where the DI within 4 hours was higher after releasing,especially for S.schiegelii.These findings indicated that the new cage-based technique could release the fish into the specified location,and has a potential to mitigate the stress reaction of fish caused by releasing process.展开更多
An optimized formulation of a sustained release tablet of Gliclazide was developed. The use of Doptimal design with a polynomial statistical model to analyze dissolution data reduced the number of laboratory tests req...An optimized formulation of a sustained release tablet of Gliclazide was developed. The use of Doptimal design with a polynomial statistical model to analyze dissolution data reduced the number of laboratory tests required to obtain an optimal dosage form. The final formulation contained 22 mg of Methocel®E15LV, 16.5 mg Methocel®E15 and 10.0 mg of Dibasic Calcium Phosphate per 30 mg Gliclazide sustained release tablet. Dissolution studies performed on tablets from 5000 tablet test batches released greater than 90 percent of loaded drug in eight hours. Drug release from the optimized tablets followed a pattern more closely similar to zero-order than other mechanisms of drug release tested. Storage of tablets in accelerated and ambient conditions for 6 and 12 months respectively did not alter any of the physico-chemical properties, drug release or the drug release rate compared to initial observations and dissolution data of the prepared tablets. The addition of potassium phosphate and monosodium phosphate to the tablet reduced the effect pH has on Gliclazide dissolution compared to the commercially available product.展开更多
基金The National Natural Science Foundation of China(Grant Nos.U20A20412,81821004,U22A20384,82225044,52273136)the National Key R&D Program of China(Grant Nos.2022YFC3501900,2023YFC2605004)+1 种基金the Beijing Natural Science Foundation(Grant Nos.L222127,L212013)the AI+Health Collaborative Innovation Cultivation Project(Grant No.Z211100003521002).
文摘Nifedipine(NF),a widely prescribed antihypertensive agent,necessitates long-term administration to maintain therapeutic efficacy.Although osmotic pump formulations,such as Bayer’s Adalat^(®),are well-established for achieving zero-order drug release,their complex manufacturing requirements significantly elevate production costs.In this study,we employed mesoporous silica as a drug carrier for nifedipine and incorporated it with an organic polymer matrix to construct an organic-inorganic hybrid nanocomposite(OIN).This nanostructured system demonstrated robust sustained-release properties in both in vitro and in vivo evaluations,with the in vitro release profile exhibiting classical first-order kinetics.To further optimize the release behavior,we combined OIN with conventional tablet-forming techniques to create an oral nanocomposite system(ONS)capable of achieving near-zero-order release.Remarkably,the cumulative release profiles of ONS closely mirrored those of the commercially available Adalat^(®)osmotic formulation across multiple time points.Moreover,we conducted a theoretical analysis of the release mechanisms underlying both OIN and ONS systems,offering novel mechanistic insights that could inform the future design of advanced sustained-release drug delivery platforms.
基金supported by Research University Grant Scheme(RUGS)University Putra Malaysia(No.03-02-12-2293RU)
文摘The fertiliser industry faces a continuing challenge to improve the efficiency of their products,particularly of nitrogenous fertilisers,and to minimise adverse impacts.Therefore,a new slow release fertilizer,ureaimpregnated woodchips from tropical plant biomass(oil palm frond and rubberwood),was developed.The morphology of the impregnated woodchips was investigated by scanning electron microscopy and the success of impregnation of urea and nitrogen deposition into the woodchips was confirmed by energy dispersive X-ray spectrometry.When nitrogen release patterns from impregnated woodchips fertiliser were simulated using a soil solution and distilled water as leaching solutions in a static condition for 768 h,release was slow and steady,although the release rate was lower in distilled water than in the soil solution.
基金supported by the National Key R&D Program of China(grant nos.2022YFB3804400 and 2019YFA0904500).
文摘Supramolecular hydrogels demonstrate considerable potential in drug delivery owing to their distinctive features,including bio-adhesiveness,self-healing behaviors,biodegradability,and biocompatibility.Nevertheless,the fabrication of supramolecular hydrogels utilizing exclusively clinically approved drugs remain challenging,typically necessitating chemical modifications of the drugs to facilitate the gelation process.In this study,we report a novel type of supramolecular hydrogel through the direct assembly of two clinically approved drugs,tobramycin and mycophenolic acid,via combined electrostatic and hydrophobic interactions.The hydrogel shows adjustable bio-adhesiveness,zero-order release kinetics,good biocompatibility,and maintained antibacterial and immunosuppressive activities.It efficiently inhibits bacterial infections and foreign body responses,and accelerates tissue healing in several subcutaneous/intraosseous implantation models accompanied by bacteria infections.This work provides a facile and promising strategy to fabricate supramolecular hydrogels with stable drug release kinetics using clinically approved drugs.
基金This study was supported by the National Natural Science Foundation of China(Nos.41501560,41606110)the Young Orient Scholars Programme of Shanghai(No.QD2017038)the Shanghai Special Research Fund for Training College’s Young Teachers(No.ZZSHOU 18025).
文摘The release technique,affecting the survival rate of fish species released for stock enhancement,plays a vital role in the effectiveness of the enhancement.In order to improve the probability of released fish settling down to bottom,a new cage-based release technique was designed and tested via a water tank with artificial reef models.Two coral reef fish species,Sebastes schlegelii and Paralichthys olivaceus were assessed using this technique.Fish behavior and distribution in water tank were recorded and compared with the traditional release release techniques.Results showed that in the case of cage-based release technique:1)when the release process is just finished,the distribution index(DI)of juveniles S.schlegelii and P.olivaceus were 97.8%and 98.9%at reef area,40%and 71.1%at release point,respectively,which was higher than those using two alternative techniques;2)its impact duration was less than that in the other two conditions,where the DI within 4 hours was higher after releasing,especially for S.schiegelii.These findings indicated that the new cage-based technique could release the fish into the specified location,and has a potential to mitigate the stress reaction of fish caused by releasing process.
文摘An optimized formulation of a sustained release tablet of Gliclazide was developed. The use of Doptimal design with a polynomial statistical model to analyze dissolution data reduced the number of laboratory tests required to obtain an optimal dosage form. The final formulation contained 22 mg of Methocel®E15LV, 16.5 mg Methocel®E15 and 10.0 mg of Dibasic Calcium Phosphate per 30 mg Gliclazide sustained release tablet. Dissolution studies performed on tablets from 5000 tablet test batches released greater than 90 percent of loaded drug in eight hours. Drug release from the optimized tablets followed a pattern more closely similar to zero-order than other mechanisms of drug release tested. Storage of tablets in accelerated and ambient conditions for 6 and 12 months respectively did not alter any of the physico-chemical properties, drug release or the drug release rate compared to initial observations and dissolution data of the prepared tablets. The addition of potassium phosphate and monosodium phosphate to the tablet reduced the effect pH has on Gliclazide dissolution compared to the commercially available product.
