MECHANISTIC STUDY OF DISSOLUTION ENHANCEMENT BY INTERACTIVE MIXTURES OF CHITOSAN WITH MELOXICAM AS MODEL

Despite the broad utility and application of SmI2in synthesis, the reagent is used in stoichiometric amounts and has a high molecular weight, resulting in a large amount of material being used for reactions requiring one or more equivalents of electrons. We report mechanistic studies on catalytic reactions of Sm(II) employing a terminal magnesium reductant and trimethyl silyl chloride in concert with a non-coordinating proton donor source. Reactions using this approach permitted reductions with as little as 1 mol% Sm. The mechanistic approach enabled catalysis employing HMPA as a ligand, facilitating the development of catalytic Sm(II) 5-exo-trig ketyl olefin cyclization reactions.

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Study of Dissolution Enhancement of Furosemide by Solid Dispersion Technique Using Different Polymer

Journal of Pharmacy and Nutrition Sciences ◽

10.29169/1927-5951.2019.09.06.6 ◽

2019 ◽

Vol 9 (6) ◽

pp. 329-338

Author(s):

Md. Didaruzzaman Sohel3 ◽

Keyword(s):

Solid Dispersion ◽

Dissolution Enhancement ◽

Dispersion Technique

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Activated carbon from molasses efficiency for Cr(VI), Pb(II) and Cu(II) adsorption: A mechanistic study

10.31221/osf.io/ecpm3 ◽

2019 ◽

Author(s):

Chem Int

Keyword(s):

Activated Carbon ◽

Phosphoric Acid ◽

Sugar Industry ◽

Chemical Activation ◽

High Surface ◽

High Surface Area ◽

Mechanistic Study ◽

Acid Mixture ◽

Maximum Adsorption Capacity ◽

Good Potential

Activated carbon was prepared from molasses, which are natural precursors of vegetable origin resulting from the sugar industry. A simple elaboration process, based on chemical activation with phosphoric acid, was proposed. The final product, prepared by activation of molasses/phosphoric acid mixture in air at 500°C, presented high surface area (more than 1400 m2/g) and important maximum adsorption capacity for methylene blue (625 mg/g) and iodine (1660 mg/g). The activated carbon (MP2(500)) showed a good potential for the adsorption of Cr(VI), Cu(II) and Pb(II) from aqueous solutions. The affinity for the three ions was observed in the following order Cu2+ Cr6+ Pb2+. The process is governed by monolayer adsorption following the Langmuir model, with a correlation coefficient close to unity.

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I. A mechanistic study of the hydrodesulfurization of methanethiol over tungsten disulfide; II. A survey of rare earth sulfides for hydrodesulfurization activity

10.31274/rtd-180813-6281 ◽

1985 ◽

Author(s):

Donald Quinn Dowd

Keyword(s):

Rare Earth ◽

Tungsten Disulfide ◽

Mechanistic Study ◽

Hydrodesulfurization Activity

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I. A mechanistic study of the hydrodesulfurization of methanethiol over tungsten disulfide; II. A survey of rare earth sulfides for hydrodesulfurization activity

10.31274/rtd-180814-6281 ◽

1985 ◽

Author(s):

Donald Quinn Dowd

Keyword(s):

Rare Earth ◽

Tungsten Disulfide ◽

Mechanistic Study ◽

Hydrodesulfurization Activity

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NANO-SIZED SOLID DISPERSION OF A POORLY WATER-SOLUBLE DRUG

Journal of Medicine and Pharmacy ◽

10.34071/jmp.2012.5.4 ◽

2012 ◽

pp. 31-35

Author(s):

Truong Dinh Thao Tran ◽

Ha Lien Phuong Tran ◽

Nghia Khanh Tran ◽

Van Toi Vo

Keyword(s):

Drug Release ◽

Droplet Size ◽

Solid Dispersion ◽

Water Soluble ◽

Drug Dissolution ◽

Dissolution Enhancement ◽

Particle Size Reduction ◽

Water Soluble Drug ◽

Poorly Water Soluble ◽

Poorly Water Soluble Drug

Purposes: Aims of this study are dissolution enhancement of a poorly water-soluble drug by nano-sized solid dispersion and investigation of machenism of drug release from the solid dispersion. A drug for osteoporosis treatment was used as the model drug in the study. Methods: melting method was used to prepare the solid dispersion. Drug dissolution rate was investigated at pH 1.2 and pH 6.8. Drug crystallinity was studied using differential scanning calorimetric and powder X-ray diffraction. In addition, droplet size and contact angle of drug were determined to elucidate mechanism of drug release. Results: Drug dissolution from the solid dispersion was significantly increased at pH 1.2 and pH 6.8 as compared to pure drug. Drug crystallinity was changed to partially amorphous. Also dissolution enhancement of drug was due to the improved wettability. The droplet size of drug was in the scale of nano-size when solid dispersion was dispersed in dissolution media. Conclusions: nano-sized solid dispersion in this research was a successful preparation to enhance bioavailability of a poorly water-soluble drug by mechanisms of crystal changes, particle size reduction and increase of wet property.

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