Hyphenating High Temperature High Performance Liquid Chromatography (HT-HPLC) with High Temperature Size Exclusion Chromatography (HT-SEC) (High Temperature Two Dimensional Liquid Chromatography (HT-HPLC x HT-SEC or HT 2D-LC)) leads to an isocratic elution in the second dimension, which in turn enables to use IR detector (quantitative detection) for monitoring the eluting polymers. Experimental...

In the present study, various mixtures of aqueous ethanol and acetone solutions were utilized to extract anthocyanins from eggplant peel by a discontinuous process to obtain a natural red-purple colorant. First, the most appropriate combination for extraction solvent was selected as ethanol 70 wt in water acidified with acetic acid 3 wt, which was determined by analysis of extraction yields and...

A novel liquid chromatographic system which enables high temperature ultrafast liquid chromatography (HTU-FLC) has been designed through the careful consideration of heat transfer, band broadening, and pressure drop. Studies of the effect of linear velocity on the HETP show that column efficiency at high velocity, especially of well-retained solutes, dramatically improves at higher temperatures...

results under the above chromatography condition, biuret compound (peqb) and the internal standard were detected at 4.5 and 13.5 minutes, respectively. limit of quantitation of the peqb was 0.1 µg/ml. accuracy of the method over the concentration range of 0.1-100 µg/ml was between 88-109%. inter- and intraday precisions were 4-19% and 6-8%, respectively. a good relationship in the form of a pow...

Online comprehensive two-dimensional liquid chromatography has become an attractive option for the analysis of complex nonvolatile samples found in various fields (e.g. environmental studies, food, life, and polymer sciences). Two-dimensional liquid chromatography complements the highly popular hyphenated systems that combine liquid chromatography with mass spectrometry. Two-dimensional liquid ...

separation of ten sedative- hypnotic drugs was performed by rp-hplc using mixed micellar mobile phase. effect of temperature, type and amount of organic modifier in mobile phase on efficiency (n) and asymmetry factor (b/a) showed that, the appropriate conditions for a good separation were 35°c and 7% (v/v) butanol in mobile phase.  variations of selectivity factor versus butanol concentration, ...

background ziziphora tenuior l. known as kakuti in persian, is used in traditional medicine for fever, dysentery, uterus infection and as an analgesic. it is used also in the treatment of gastrointestinal disorders as carminative, or remedy of diarrhea or nausea. major components of plant essential oil including pulegone, isomenthone, thymol, menthone, and piperitone are suggested to be respons...