Sodium di(undecenyl) tartarate monomer (SDUT), a vesicle-forming amphiphilic compound possessing two hydrophilic carboxylate head groups and two hydrophobic undecenyl chains gemini surfactant, was prepared and polymerized to form a polymeric gemini surfactant (i.e., poly-SDUT). These anionic surfactant systems with carboxylate (SDUT and poly-SDUT) and sulfate (sodium dodecyl sulfate, SDS) head ...

The paper applies MEKC technique to simultaneously carry out quantitative analysis on dairy product’s melamine (Mel) and 5-hydroxymethyl furfural (HMF) bi-component. The quantization analytic experiment starts with a systematic research on operating voltage, electrophoretic buffer solution gravity and optimum pH value, which further influences additives’ concentration as well as other factors, ...

Sodium di(2-ethylhexyl) sulfosuccinate (DOSS) and sodium di(2-ethylhexyl) phosphate (NaDEHP) surfactants, with double alkyl chains and negatively charged headgroups, were characterized using fluorescence quenching, densitometry, and tensiometry techniques to determine their aggregation number, partial specific volume, and critical aggregation concentration. These two surfactants were then appli...

The applicability of micellar electrokinetic capillary chromatography (MEKC) for the separation of benzodiazepine (BZD) derivates with different structural characteristics has been studied. Efforts were first focused on the optimization of the analytical conditions, on the effects of buffer concentration, surfactant concentration and buffer pH on the separation. To manipulate selectivity of the...

Micellar electrokinetic chromatography (MEKC) conditions were developed to analyze the constituents of Scutellariae Radix (SR) and Scutellaria baicalensis roots. Using the MEKC method, the major flavonoid constituents of baicalin, baicalein and wogonin of wild and cultivated S. baicalensis roots were compared. In a preliminary comparison of electropherogram, one special peak was found in a wild...

A new micellar electrokinetic chromatography (MEKC) procedure has been developed that allows the use of the anionic surfactant sodium dodecyl sulfate (SDS) together with separation buffers at pHs as low as 1. The technique is based on the employment of a high molecular weight polyethylenimine (PEI)-coated capillary that provides strong cathodal electroosmotic flows at acidic pHs when SDS is add...

A micellar electrokinetic chromatographic (MEKC) method has been established for the identification and determination of acid-catalyzed proanthocyanidin cleavage products in the presence of phloroglucinol. Using fused-silica capillaries (50=57 cm, 22 kV) with phosphate buffer containing sodium dodecyl sulfate as the surfactant and b-cyclodextrin as modifier, structurally similar phloroglucinol ...

A simple and efficient MEKC method was developed to simultaneously determine human insulin, its five analogues, the main degradation products and the excipients usually present in injection formulations. A very fast method with a total analysis time of 3 min was then successfully validated for the analysis of human insulin and the quality control of commercial formulations was carried out.

The principal advantage of the use of Shopl'skii effect (low temperature spectrum) is that spectral sharpening occurs both in absorption and emission. However, thus far using the technique of capillary electrophoresis/low temperature fluorescence spectroscopy (CE/LTFS) either at 77 or 4.2 K remains difficult to obtain an on-line spectrum, if the analyte is present at low concentration. This pap...