Flow Injection Gradient Technique in Spectrophotometric Determination of Formation Constants of Micromolecule-Cyclodextrin Complexes

Cucurbit[7]uril complexations of Good's buffers

“…The DpK a value of 3.1 for CHES allows for a binding constant estimation (K b CB [7] ¼ K a CB [7] (10 ÀDpKa )) 38,39 of K b CB [7] ¼ 3 Â 10 4 dm 3 mol À1 for the conjugate base of CHES. The binding constant for this form of CHES with the b-cyclodextrin (b-CD) host has been reported to be 490 AE 20 dm 3 mol À1 (pH 10.5, with a similar value for CAPS) 28 and 440 AE 30 dm 3 mol À1 (pH 11.6). 29 The zwitterionic form of CHES binds very much weaker (about 30 dm 3 mol À1 ) with b-CD, which would arise from a decrease in the pK a value upon complexation.…”

“…1), which are non-complexing towards metal ions. 26,27 There has, however, been little in the way of studies on the interactions of these pH buffers with macrocyclic host molecules, [28][29][30] such as cyclodextrins, calixarenes, and cucurbiturils, which are of increasing interest in biological, biochemical, and medicinal applications. [31][32][33][34] In this study, the host-guest complexations of a series of Good's (and related) pH buffers ( Fig.…”

Spectrophotometric Determination of Fluoxetine by Batch and Flow Injection Methods

“…21) Koupparis et al used flow injection gradient technique in spectrophotometric determination of formation constant of the inclusion complex of PHP with b-CD as 2.4(Ϯ0.2)ϫ10 4 l mol Ϫ1 in carbonate buffer of pH 10.5 and at 23.5°C. 22) The aim of the present study was to develop simple, sensitive, and rapid flow injection analysis (FIA) and batch methods for spectrophotometric determination of FXT based on its competitive complexation reaction with PHP-b-CD inclusion complex. The spectrophotometric determination of FXT was compared for batch and FIA systems.…”

Investigation of the sorption properties of β-cyclodextrin-based polyurethanes with phenolic dyes and naphthenates

“…The phenolic dyes reported herein are p-nitrophenol (PNP) and phenolphthalein (phth) which have been used previously for the estimation of the surface area of sorbent materials [34,35] and an understanding of the molecular recognition by b-CD domains [31,[36][37][38], respectively. NAs have been extensively described in previous work [29,39,40].…”