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11.
Evaluation of the disintegration time of rapidly disintegrating tablets via a novel method utilizing a CCD camera 总被引:6,自引:0,他引:6
Morita Y Tsushima Y Yasui M Termoz R Ajioka J Takayama K 《Chemical & pharmaceutical bulletin》2002,50(9):1181-1186
Many kinds of rapidly disintegrating or oral disintegrating tablets (RDT) have been developed to improve the ease of tablet administration, especially for elderly and pediatric patients. In these cases, knowledge regarding disintegration behavior appears important with respect to the development of such a novel tablet. Ordinary disintegration testing, such as the Japanese Pharmacopoeia (JP) method, faces limitations with respect to the evaluation of rapid disintegration due to strong agitation. Therefore, we have developed a novel apparatus and method to determine the dissolution of the RDT. The novel device consists of a disintegrating bath and CCD camera interfaced with a personal computer equipped with motion capture and image analysis software. A newly developed RDT containing various types of binder was evaluated with this protocol. In this method, disintegration occurs in a mildly agitated medium, which allows differentiation of minor distinctions among RDTs of different formulations. Simultaneously, we were also able to detect qualitative information, i.e., morphological changes in the tablet during disintegration. This method is useful for the evaluation of the disintegration of RDT during pharmaceutical development, and also for quality control during production. 相似文献
12.
An enantiospecific coupling of propargylic esters and carbonates with arylboronic acids has been developed using a palladium catalyst. Optically active 1,3-disubstituted allenes were synthesized with high enantiomeric excesses by carrying out the reactions under basic aqueous conditions. 相似文献
13.
Kozo Tsuji 《Journal of polymer science. Part A, Polymer chemistry》1973,11(8):2069-2075
When ethylene–acrolein copolymer was irradiated at ?196°C with ultraviolet light, a sharp singlet spectrum with a g value of about 2.001 was predominant. This spectrum is attributed to acyl radicals, which are produced by dissociation of a hydrogen atom from an aldehyde group. At the same time it is supposed that dissociation of formyl groups also took place to give alkyl radicals, CO, and H2. The alkyl radicals reacted with CO molecules to give acyl radicals at ?78°C under vacuum. Peroxy radicals were produced when the sample irradiated at ?196°C in the presence of air was treated at ?78°C. The sample irradiated at ?196°C was warmed to near 0°C and an apparent singlet spectrum with a g value of about 2.004 was observed. This spectrum was tentatively assigned as due to free radicals of the type 相似文献
14.
The negative ion mass spectra of chlorine-containing molecules have been measured using a double focusing mass spectrometer with a photographic plate detector. The formulae of the negative ions not previously assigned using an electron multiplier detector have now been assigned. 相似文献
15.
Morita Y Murata T Fukui K Yamada S Sato K Shiomi D Takui T Kitagawa H Yamochi H Saito G Nakasuji K 《The Journal of organic chemistry》2005,70(7):2739-2744
[structure: see text] Novel hydrogen-bonded charge-transfer salts of TCNQ with mono- and diprotonated 4,4'-biimidazolium were synthesized in order to demonstrate the high potential of the 4,4'-biimidazole system in a molecular conductor from the viewpoint of crystal engineering and electronic modulation. Crystal structure analyses of neutral 4,4'-biimidazole and TCNQ salts revealed the formation of two types of hydrogen-bonding modes of the 4,4'-biimidazole moiety depending on the protonated states. Neutral 4,4'-biimidazole possessed a linear chain mode of hydrogen-bonding to construct two-dimensional network. In the TCNQ salt of monoprotonated 4,4'-biimidazolium, the 4,4'-biimidazole moiety formed a dimer by a complementary mode of hydrogen-bonding. In contrast, the salt of diprotonated 4,4'-biimidazolium showed a double linear chain mode of hydrogen-bonding to construct a three-dimensional network. The formation of two types of hydrogen-bonding modes made the difference in the stacking patterns of TCNQ columns and in their transport properties. The TCNQ salt of diprotonated 4,4'-biimidazolium exhibited high electrical conductivity (sigma(rt) = 1.1 x 10(-1) S cm(-1)). 相似文献
16.
Hideo Hirai Kozo Sawada Matsuhiko Aratani Masashi Hashimoto 《Tetrahedron letters》1985,26(14):1739-1742
A stereoselective kinetic protonation of the azetidinone enolate was studied and an efficient synthesis of(cis) was achieved via aldol reaction of with acetone followed by the kinetic protonation with Ph3SnH as proton source. 相似文献
17.
Phenols are deprotected with weak bases from their tert-butoxycarbonyl (Boc) derivatives. Boc deprotection with bases can avoid side reactions during the deprotection with acids. We note the lability of the Boc to bases and are able to utilize it as a new cleavage condition for synthetic studies. 相似文献
18.
Sodium poly(styrenesulfonate)(polySSNa)-grafted polymer nanoparticles were synthesized by core-cross-linking of block copolymer micelles and subsequent chemical transformation. Block copolymers, poly(p-((1-methyl)silacyclobutyl)styrene-block-poly(neopentyl p-styrenesulfonate)s, polySBS-b-polySSPen, were synthesized by nitroxy-mediated living radical polymerization. The block copolymers formed micelles (Rh=15-23 nm, where Rh represents the hydrodynamic radius) with a polySBS core and polySSPen shell in acetone. The micelle core was cross-linked by ring-opening polymerization of silacyclobutyl groups in polySBS. Hydrolysis of the neopentyl groups provided polySSNa-grafted nanoparticles. The Rh of the particles before the hydrolysis ranged from 12 to 21 nm in acetone, while they varied to the range from 50 to 110 nm in water after the hydrolysis. 相似文献
19.
Masahiro Manabe Toshihiro Ochi Hideo Kawamura Hajime Katsu-ura Masaki Shiomi Mandeep Singh Bakshi 《Colloid and polymer science》2005,283(7):738-746
The partial molar volumes (Va) of 1-alkanols (carbon number, m=5, 6, 7) in - and -cyclodextrin (CD) solutions at 5.00 mmol kg–1 have been determined as a function of alkanol concentration (Ca) between 293.2 and 308.2 K by using a dilatometer. It has been observed that with an increase in Ca, Va increased in -CD solution but decreased in -CD solution, asymptotically to a value of Va in CD-free water. The dependence of Va on Ca provided the binding constant (K) of 1:1 complex, the volume change in complex formation, and the partial molar volume of complex itself. The complex formation mechanism has been discussed on the basis of these values and their carbon number dependences in the respect of geometric behavior, hydrophobic interaction, and van der Waals interaction. It is concluded that the CD cavity in water is not rigid but flexible for fitting in nicely with guest molecule. 相似文献
20.
H Ikeda Y Shimonishi M Ohmura K Kishimoto K Kosakai K Hamada H Ochi 《Radioisotopes》1990,39(11):487-492
Textural features for phantom images were extracted. Texture parameters which represent RI distribution--skew, energy, entropy and angular second moment were used. But, it was difficult to analyse the images using discriminant analysis for textural features, because textural features had statistical noise. Therefore fuzzy reasoning was adapted to analyse the images. Textural features for six kinds of images were showed using membership function. The possibility to the image was evaluated using the value of membership function on each images. Fuzzy reasoning could be done easily using max-min composition formula. The reasoning was found more suitable to analyse the images than discriminant analysis and will be considered useful for analysis of clinical scintigrams. 相似文献