To enhance the dissolution of poorly soluble mefenamic acid,self-emulsifying formulation(SEF),composing of oil,surfactant and co-surfactant,was formulated.Among the oils and surfactants studied,Imwitor■ 742,Tween■ 6...To enhance the dissolution of poorly soluble mefenamic acid,self-emulsifying formulation(SEF),composing of oil,surfactant and co-surfactant,was formulated.Among the oils and surfactants studied,Imwitor■ 742,Tween■ 60,Cremophore■ EL and Transcutol■ HP were selected as they showed maximal solubility to mefenamic acid.The ternary phase diagram was constructed to find optimal concentration that provided the highest drug loading.The droplet size after dispersion and drug dissolution of selected formulations were investigated.The results showed that the formulation containing Imwitor■ 742,Tween■ 60 and Transcutol■ HP(10:30:60)can encapsulate high amount of mefenamic acid.The dissolution study demonstrated that,in the medium containing surfactant,nearly 100% of mefenamic acid were dissolved from SEF within 5 min while 80% of drugs were dissolved from the commercial product in 45 min.In phosphate buffer(without surfactant),80% of drug were dissolved from the developed SEF within 5 min while only about 13% of drug were dissolved in 45 min,from the commercial product.The results suggested that the SEF can enhance the dissolution of poorly soluble drug and has a potential to enhance drug absorption and improve bioavailability of drug.展开更多
The purpose of this study was to investigate the hydrolyzation of aspirin during the process of dissolution testing for aspirin delayed-release tablets. Hydrolysis product of salicylic acid can result in adverse effec...The purpose of this study was to investigate the hydrolyzation of aspirin during the process of dissolution testing for aspirin delayed-release tablets. Hydrolysis product of salicylic acid can result in adverse effects and affect the determination of dissolution rate assaying. In this study, the technique of differential spectra was employed, which made it possible to monitor the dissolution testing in situ. The results showed that the hydrolyzation of aspirin made the percentage of salicylic acid exceed the limit of free salicylic acid (4.0), and the hydrolyzation may affect the quality detection of aspirin delayed-release tablets.展开更多
The effects of temperature and wavelength choice on in-situ dissolution test instrument of Cimetidine were studied. Absorbance (A)〈 1.0 is required when using a fiber-optic dissolution test system. The detection wa...The effects of temperature and wavelength choice on in-situ dissolution test instrument of Cimetidine were studied. Absorbance (A)〈 1.0 is required when using a fiber-optic dissolution test system. The detection wavelength of 2 (218 nm) was replaced by 244 nm to carry out this test. The absorbance of Cimetidine solution at different temperature showed an obvious change. Calibration of Cimetidine solution should be tested at the same temperature (37° C) with the test solution. A suitable wavelength with smaller tangent slope could be chosen for in-situ dissolution test of Cimetidine tablets.展开更多
This research work blooms the new idea of developing a safe and controlled drug releasing matrix using multi-walled carbon nanotubes(MWCNTs).In aqueous solution,uniform and highly stable dispersion of MWCNTs was obtai...This research work blooms the new idea of developing a safe and controlled drug releasing matrix using multi-walled carbon nanotubes(MWCNTs).In aqueous solution,uniform and highly stable dispersion of MWCNTs was obtained after secondary functionalization with polyethylene glycol(PEG)which was studied by Fourier transmission infrared spectroscopy(FTIR)and thermogravimetric analysis(TGA).Solution casting method was used to prepare MWCNTs/gelatin-chitosan nanocomposite films and the effect of MWCNTs on physico-mechanical,thermal and water uptake properties of the nanocomposites were evaluated.Incorporation of MWCNTs into the porous gelatin-chitosan matrix showed interesting stiffness and dampness along with developed microfibrillar structures within the pore walls intended at being used in tissue engineering of bone or cartilage.A common antibiotic drug,ciprofloxacin was incorporated into nanocomposite matrix.The evaluation of the effect of MWCNTs on drug release rate by dissolution test and antimicrobial susceptibility test was performed.Sharp release of the drug was found at early stages(~1 h),but the rate was reduced afterwards,showing a sustained release.It was observed that for all microorganisms,the antibacterial activities of drug loaded MWCNTs/gelatin-chitosan nanocomposites were higher than that of drug loaded gelatin-chitosan composite films containing no MWCNTs.Comparative statistical studies by ANOVA techniques also showed remarkable difference between the antibacterial activities,exhibited by MWCNTs-incorporated and non-incorporated composite films.展开更多
The solid form of drugs plays a central role in optimizing the physicochemical properties of drugs,and new solid forms will provide more options to achieve the desirable pharmaceutical profiles of drugs.Recently,certa...The solid form of drugs plays a central role in optimizing the physicochemical properties of drugs,and new solid forms will provide more options to achieve the desirable pharmaceutical profiles of drugs.Recently,certain drugs have been found to form crystalline inclusion complexes(ICs) with multiple types of linear polymers,representing a new subcategory of pharmaceutical solids.In this study,we used diflunisal(DIF) as the model drug host and extended the guest of drug/polymer ICs from homopolymers to block copolymers of poly(ethylene glycol)(PEG) and poly(s-caprolactone)(PCL).The block length in the guest copolymers showed a significant influence on the formation,thermal stability and dissolution behavior of the DIF ICs.Though the PEG block could hardly be included alone,it could indeed be included in the DIF ICs when the PCL block was long enough.The increase of the PCL block length produced IC crystals with improved thermal stability.The dissolution profiles of DIF/block copolymer ICs exhibited gradually decreased aqueous solubility and dissolution rate with the increasing PCL block length.These results demonstrate the possibility of using drug/polymer ICs to modulate the desired pharmaceutical profiles of drugs in a predictable and controllable manner.展开更多
基金Financial support from The Thailand Research Fund(grant number BRG5480013)is greatly acknowledged.
文摘To enhance the dissolution of poorly soluble mefenamic acid,self-emulsifying formulation(SEF),composing of oil,surfactant and co-surfactant,was formulated.Among the oils and surfactants studied,Imwitor■ 742,Tween■ 60,Cremophore■ EL and Transcutol■ HP were selected as they showed maximal solubility to mefenamic acid.The ternary phase diagram was constructed to find optimal concentration that provided the highest drug loading.The droplet size after dispersion and drug dissolution of selected formulations were investigated.The results showed that the formulation containing Imwitor■ 742,Tween■ 60 and Transcutol■ HP(10:30:60)can encapsulate high amount of mefenamic acid.The dissolution study demonstrated that,in the medium containing surfactant,nearly 100% of mefenamic acid were dissolved from SEF within 5 min while 80% of drugs were dissolved from the commercial product in 45 min.In phosphate buffer(without surfactant),80% of drug were dissolved from the developed SEF within 5 min while only about 13% of drug were dissolved in 45 min,from the commercial product.The results suggested that the SEF can enhance the dissolution of poorly soluble drug and has a potential to enhance drug absorption and improve bioavailability of drug.
基金supported by the Xinjiang Medical University Scientific Innovation Fund (No. XJC201129)Xinjiang Uygur Autonomous Region Natural Science Fund (No. 2011211A041)
文摘The purpose of this study was to investigate the hydrolyzation of aspirin during the process of dissolution testing for aspirin delayed-release tablets. Hydrolysis product of salicylic acid can result in adverse effects and affect the determination of dissolution rate assaying. In this study, the technique of differential spectra was employed, which made it possible to monitor the dissolution testing in situ. The results showed that the hydrolyzation of aspirin made the percentage of salicylic acid exceed the limit of free salicylic acid (4.0), and the hydrolyzation may affect the quality detection of aspirin delayed-release tablets.
基金the Xinjiang Uygur Autonomous Region Natural Science Fund (No.2011211A041) Xinjiang Uygur Autonomous Region Science and Technology Plan (No.200910107)
文摘The effects of temperature and wavelength choice on in-situ dissolution test instrument of Cimetidine were studied. Absorbance (A)〈 1.0 is required when using a fiber-optic dissolution test system. The detection wavelength of 2 (218 nm) was replaced by 244 nm to carry out this test. The absorbance of Cimetidine solution at different temperature showed an obvious change. Calibration of Cimetidine solution should be tested at the same temperature (37° C) with the test solution. A suitable wavelength with smaller tangent slope could be chosen for in-situ dissolution test of Cimetidine tablets.
文摘This research work blooms the new idea of developing a safe and controlled drug releasing matrix using multi-walled carbon nanotubes(MWCNTs).In aqueous solution,uniform and highly stable dispersion of MWCNTs was obtained after secondary functionalization with polyethylene glycol(PEG)which was studied by Fourier transmission infrared spectroscopy(FTIR)and thermogravimetric analysis(TGA).Solution casting method was used to prepare MWCNTs/gelatin-chitosan nanocomposite films and the effect of MWCNTs on physico-mechanical,thermal and water uptake properties of the nanocomposites were evaluated.Incorporation of MWCNTs into the porous gelatin-chitosan matrix showed interesting stiffness and dampness along with developed microfibrillar structures within the pore walls intended at being used in tissue engineering of bone or cartilage.A common antibiotic drug,ciprofloxacin was incorporated into nanocomposite matrix.The evaluation of the effect of MWCNTs on drug release rate by dissolution test and antimicrobial susceptibility test was performed.Sharp release of the drug was found at early stages(~1 h),but the rate was reduced afterwards,showing a sustained release.It was observed that for all microorganisms,the antibacterial activities of drug loaded MWCNTs/gelatin-chitosan nanocomposites were higher than that of drug loaded gelatin-chitosan composite films containing no MWCNTs.Comparative statistical studies by ANOVA techniques also showed remarkable difference between the antibacterial activities,exhibited by MWCNTs-incorporated and non-incorporated composite films.
基金financially supported by the National Natural Science Foundation of China(Nos.21434008,21374054)National Basic Research Program of China(973 Program,No.2014CB932202)
文摘The solid form of drugs plays a central role in optimizing the physicochemical properties of drugs,and new solid forms will provide more options to achieve the desirable pharmaceutical profiles of drugs.Recently,certain drugs have been found to form crystalline inclusion complexes(ICs) with multiple types of linear polymers,representing a new subcategory of pharmaceutical solids.In this study,we used diflunisal(DIF) as the model drug host and extended the guest of drug/polymer ICs from homopolymers to block copolymers of poly(ethylene glycol)(PEG) and poly(s-caprolactone)(PCL).The block length in the guest copolymers showed a significant influence on the formation,thermal stability and dissolution behavior of the DIF ICs.Though the PEG block could hardly be included alone,it could indeed be included in the DIF ICs when the PCL block was long enough.The increase of the PCL block length produced IC crystals with improved thermal stability.The dissolution profiles of DIF/block copolymer ICs exhibited gradually decreased aqueous solubility and dissolution rate with the increasing PCL block length.These results demonstrate the possibility of using drug/polymer ICs to modulate the desired pharmaceutical profiles of drugs in a predictable and controllable manner.