Solubility of Cyclodextrins and Drug/Cyclodextrin Complexes

Publisher's version (útgefin grein)Cyclodextrins (CDs), a group of oligosaccharides formed by glucose units bound together in a ring, show a promising ability to form complexes with drug molecules and improve their physicochemical properties without molecular modifications. The stoichiometry of drug/CD complexes is most frequently 1:1. However, natural CDs have a tendency to self-assemble and form aggregates in aqueous media. CD aggregation can limit their solubility. Through derivative formation, it is possible to enhance their solubility and complexation capacity, but this depends on the type of substituent and degree of substitution. Formation of water-soluble drug/CD complexes can increase drug permeation through biological membranes. To maximize drug permeation the amount of added CD into pharmaceutical preparation has to be optimized. However, solubility of CDs, especially that of natural CDs, is affected by the complex formation. The presence of pharmaceutical excipients, such as water-soluble polymers, preservatives, and surfactants, can influence the solubilizing abilities of CDs, but this depends on the excipients’ physicochemical properties. The competitive CD complexation of drugs and excipients has to be considered during formulation studies.Peer Reviewe

Solubility of Cyclodextrins and Drug/Cyclodextrin Complexes

Publisher's version (útgefin grein)Cyclodextrins (CDs), a group of oligosaccharides formed by glucose units bound together in a ring, show a promising ability to form complexes with drug molecules and improve their physicochemical properties without molecular modifications. The stoichiometry of drug/CD complexes is most frequently 1:1. However, natural CDs have a tendency to self-assemble and form aggregates in aqueous media. CD aggregation can limit their solubility. Through derivative formation, it is possible to enhance their solubility and complexation capacity, but this depends on the type of substituent and degree of substitution. Formation of water-soluble drug/CD complexes can increase drug permeation through biological membranes. To maximize drug permeation the amount of added CD into pharmaceutical preparation has to be optimized. However, solubility of CDs, especially that of natural CDs, is affected by the complex formation. The presence of pharmaceutical excipients, such as water-soluble polymers, preservatives, and surfactants, can influence the solubilizing abilities of CDs, but this depends on the excipients’ physicochemical properties. The competitive CD complexation of drugs and excipients has to be considered during formulation studies.Peer Reviewe

Combining Cellulose and Cyclodextrins: Fascinating Designs for Materials and Pharmaceutics

Cellulose and cyclodextrins possess unique properties that can be tailored, combined, and used in a considerable number of applications, including textiles, coatings, sensors, and drug delivery systems. Successfully structuring and applying cellulose and cyclodextrins conjugates requires a deep understanding of the relation between structural, and soft matter behavior, materials, energy, and function. This review focuses on the key advances in developing materials based on these conjugates. Relevant aspects regarding structural variations, methods of synthesis, processing and functionalization, and corresponding supramolecular properties are presented. The use of cellulose/cyclodextrin conjugates as intelligent platforms for applications in materials science and pharmaceutical technology is also outlined, focusing on drug delivery, textiles, and sensors

Predicting Factors for Smoking Behavior among Women Who Frequent Nightlife Entertainment Venues around a University in the Northern Region of Thailand

This cross-sectional survey aims to study the behaviors and predictors for smoking behaviors among women who frequent nightlife entertainment venues around a university in the northern region of Thailand. Samples comprised 279 women who visited nightlife venues around a university in the northern region of Thailand. A questionnaire was used for data collection. Data were analyzed by chi-square and binary logistic regression. The results found that women who frequented nightlife venues and smoked accounted for 32% and 22% of those who smoked inside such venues. Furthermore, the factors identified as predictive of smoking behavior among women who frequented nightlife entertainment venues included frequently visiting nightlife venues more than 3 days per week (odds ratio (OR) = 8.89, 95% confidence interval (CI): 3.31-23.90), having a positive attitude toward smoking (OR = 3.13, 95% CI: 1.56-6.28), having a smoking family member (OR = 2.78, 95% CI: 1.37-5.66), and having a smoking partner (OR = 4.86, 95% CI: 2.38-9.93). Therefore, relevant agencies should continuously promote the right attitudes about smoking to Thai women who frequent nightlife entertainment venues

Effect of γ-cyclodextrin on solubilization and complexation of irbesartan: influence of pH and excipients.

To access publisher's full text version of this article click on the hyperlink at the bottom of the pageIn effort to prepare an eye drop formulation of irbesartan, the effect of γ-cyclodextrin complexation on irbesartan solubilization in aqueous solutions was investigated. The optimum cyclodextrin concentration for formation of irbesartan/cyclodextrin inclusion complex was found to be 10% (w/v) and the solubility of ionized irbesartan/γ-cyclodextrin complex (at pH 7.2) was shown to be three fold greater than that of the unionized complex (at pH 4.3). The irbesartan flux through semipermeable membranes increased with increasing γ-cyclodextrin concentration at both pH values. However, the ionized complex displayed decrease in the drug permeation coefficient with increasing cyclodextrin concentration. The effect of four pharmaceutical excipients on the cyclodextrin solubilization was investigated. EDTA, hydroxypropyl methylcellulose, and tyloxapol increased complexation efficiency of γ-cyclodextrin while benzalkonium chloride had negligible effect. The largest solubilization was observed in the eye drop vehicle that contained all four excipients in addition to γ-cyclodextrin. Dynamic light scattering measurements disclosed that excipients had impact on size of complex aggregates and consequently on the drug flux through the semipermeable membranes. Complex of irbesartan/γ-cyclodextrin was characterized by FT-IR, (1)H NMR, XRPD, and TEM techniques.Icelandic Center of Research, (RANNÍS), University of Icelan