Cyclodextrin Multicomponent Complexes: Pharmaceutical Applications

Cyclodextrins (CDs) are naturally available water-soluble cyclic oligosaccharides widely used as carriers in the pharmaceutical industry for their ability to modulate several properties of drugs through the formation of drug–CD complexes. The addition of an auxiliary substance when forming multicomponent complexes is an adequate strategy to enhance complexation efficiency and to facilitate the therapeutic applicability of different drugs. This review discusses multicomponent complexation using amino acids; organic acids and bases; and water-soluble polymers as auxiliary excipients. Special attention is given to improved properties by including information on the solubility, dissolution, permeation, stability and bioavailability of several relevant drugs. In addition, the use of multicomponent CD complexes to enhance therapeutic drug effects is summarized.

Wound dressings and soft dosage forms based on collagen for the treatment of wounds of various etiologies

Collagen is a promising auxiliary substance in the manufacture of soft dosage forms (DF). Wound dressings and gels based on collagen are of great interest, as they allow speeding up the healing process, are completely utilized by the body, and can serve as a carrier for various medicinal and biologically active substances. An important advantage of using collagen is a large number of sources of its acquisition, which minimizes the risks of missing the necessary basis for the production of new medicines.

Prospects of using EMDEX® in chewable tablet technology

A study of the technological properties of the auxiliary substance EMDEX® (JRS Pharma, Germany) has been made. On its basis the authors have drawn a conclusion about the prospect of its use in the chewable tablet technology.

Azocoupling Reaction Of Cephalosporin Antibiotics With 8-Hydroxyquinoline And Its Application In The Analysis Of Medicinal Products

Methods for spectrophotometric determination of cephalosporin antibiotics ceftazidime and ceftriaxone using azocoupling reactions with 8-hydroxyquinoline have been developed. Optimal conditions for the diazotization of antibiotics in hydrochloric acid (CHCl = 12 M) and subsequent azocoupling with 8-hydroxyquinoline in alkaline medium (0.16 M NaOH in the final volume) were established. The of azocopling products of violet and light red colors are formed, which are characterized by absorption maxima at 553 nm (ε553 = 6.31·103 M-1 cm-1) and 550 nm (ε550 = 1.45·104 M-1 cm-1) for ceftazidime and ceftriaxone, respectively. Stoichiometric ratios of the azo compounds components were determined using continuous variations methods and in both cases are 1:1. Sensitive methods of spectrophotometric determination of ceftazidime (LOD = 1.81∙10-6 M) and ceftriaxone (LOD = 5.92·10-7 M) have been developed. The selectivity of cephalosporin antibiotics spectrophotometric determination in the presence of auxiliary substance (sodium carbonate) has been investigated. The elaborated methods has been approved during the analyses of model solutions and the single component drug. The recommended procedure is well suited for the ceftazidime and ceftriaxone assay in medicine to assure high standards of quality control.

Spectroscopic Investigation for Photo stability of Hydrochlorothiazide Complexes with β-Cyclodextrin and HPMC.

Hydrochlorothiazide (HCT) is a poorly water-soluble drug. The aim of this study was to determine whether inclusion complexes between β-cyclodextrin and HCT are formed and also studied effect of auxiliary substance (HPMC) on HCT, photo-stability of HCT and to characterize these. Equimolar HCT/ βCD solid systems in the presence or absence of 0.2% (w/v) of HPMC were prepared by kneading method. The systems were characterized by phase solubility, Dissolution study, FTIR, DSC and the photo-stability test followed by u.v. spectroscopy. The results suggest that true binary and ternary inclusion complex. The test results have proved that the complexed HCT with hydroxypropyl β- cyclodextrin enhance the photo degradation rate and resolute the optimal molar ratio HCT to hydroxypropyl β- cyclodextrin as 1:1.

SYNTHESIS OF [(Ca1-xSrx)2-2y](Ti2-2yLi2y)Si2yO6-y CERAMIC AND ITS APPLICATION IN EFFICIENT PLASMA DECOMPOSITION OF CO2

According to both the first principle and materials chemistry, a method for fabricating [( Ca 1-x Sr x)2-2y]( Ti 2-2y Li 2y) Si 2y O 6-y ceramic was investigated. It was considered that the sintering was promoted by self-accelerated diffusion due to the formation of point defects caused by doping with Li 2 Si 2 O 5. Consequently, a concept of non-stoichiometrically activated sintering, which was enhanced by point defects without the help of a grain boundary phase, was systematically studied in the Ca 1-x Sr x TiO 3- Li 2 Si 2 O 5 system. The mechanical and dielectric properties of [( Ca 1-x Sr x)2-2y]( Ti 2-2y Li 2y) Si 2y O 6-y were greatly enhanced by adding Li 2 Si 2 O 5. To improve CO2 decomposition activity, [( Ca 1-x Sr x)2-2y]( Ti 2-2y Li 2y) Si 2y O 6-y, which possesses both high permittivity and high dielectric strength was used as a dielectric barrier to decompose CO2 by dielectric barrier discharges (DBDs) plasma without using any catalyst and auxiliary substance. It successfully generated DBDs plasma and the CO2 conversion was much higher than that using an alumina or a silica glass barrier which was widely used as the dielectric barrier in previous studies.

Beiträge zur Chemie des Phosphors, 49.

The 31P- and 1H-NMR spectra of PH3, PD3, P2H4, P2D4, P3H5, and of a mixture of higher phosphanes were investigated at -60° to -93°C. The chemical shifts of the 31P-spectra were determined against TMS by means of INDOR measurements and converted to the shifts against 85% H3PO4 at 30°C using (CH3O)3P as an auxiliary substance. By the same method a P4O6/CS2 solution was calibrated as a 31P-low temperature standard.While liquid P2H4 exhibits no remarkable association, it shows an obvious influence on PH3 dissolved in it. By means of double resonance experiments the equivalency of protons in P2H4 could be demonstrated as well as the AB2 system expected for P3H5