Advanced Chromatographic Techniques Research Articles

Improved liquid chromatography fingerprint of fat‐soluble Radix isatidis extract using multi‐wavelength combination technique

We first investigated liquid chromatography (LC) fingerprint method using multi-wavelength combination technique, and successfully used this method for the analysis of a fat-soluble extract from Radix isatidis. LC fingerprints of fat-soluble R. isatidis extracts from 11 origins were established using the Origin software and Similarity Evaluation System for Chromatographic Fingerprints of traditional Chinese medicine (TCM). The typical LC fingerprints of fat-soluble extracts from R. isatidis were first established, and the reference chromatogram was also generated with 24 common peaks showing large peak areas and good separation from adjacent peaks. Seven common characteristic peaks were identified for the first time: anthranilic acid, syringic acid, benzoic acid, salicylic acid, tryptanthrin, indigo and indirubin. The total peak areas of 24 common peaks were more than 80% of the total peak areas. Hierarchical clustering analysis (HCA) of 11 R. isatidis samples was performed, and the results show that the differences between 11 origin R. isatidis were large. Principal component analysis (PCA) on 24 common peaks was obtained to find the possible chemical markers for the discrimination of different samples. The loading plot indicated that peaks 8, 11, 13 and 14 may have more influence on the discrimination of the samples. All these were useful for evaluating and controlling the quality of R. isatidis. Our work provides a general model of chromatogram combination at multi-wavelength detection to study the complex or the undeveloped materials, which can be used to scientifically ensure the quality of such samples and deeply do qualitative, quantitative and multicomponent pharmacodynamic research combined with modern advanced chromatographic technique.

Advanced and innovative chromatographic techniques for the study of citrus essential oils

AbstractA brief description is given of advanced chromatographic techniques currently employed in citrus essential oil analysis (the interactive use of linear retention indices and MS spectra probability matching in GC–MS; on‐line ‘heart cutting’ multidimensional chromatographic techniques, comprehensive GC and LC; fast GC and GC–MS; fast HPLC; HPLC–MS). A series of applications are reported, demonstrating both the valid and the potential of these methods. Copyright © 2005 John Wiley & Sons, Ltd.

Isolation of Palm Tocols Using Supercritical Fluid Chromatography

Crude palm oil contains 600 to 1000 ppm of tocols in the form of tocopherols and tocotrienols. These palm tocols have been isolated and analyzed in the past by various chromatographic techniques such as open column chromatography, high-performance liquid chromatography, as well as thin-layer chromatography. Supercritical fluid chromatography (SFC) has emerged as a more advanced chromatographic technique in recent years. The tocols present in palm oil are successfully isolated using SFC. Identification of these tocols is supported by various spectroscopic techniques such as 1H NMR, 13C NMR, and mass spectrometry.

Directed search for plant constituents: a case study concerning flavonoids in Norway spruce

The reported content of flavonoids in the needles of Norway spruce, Picea abies, has been used as a basis for a directed search for compounds previously undetected in this species. Combined with advanced chromatographic methods and sensitive detection techniques, the directed search approach assisted in the identification of the novel flavonols, myricetin 3- O- (6″-acetylglucoside) and syringetin 7- O-glucoside, and several other flavonoids isolated for the first time from this species.

Synthetic and chemical studies on pheromones of some forest pest insects

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A new partition agent for use in the rapid separation of fatty acid esters by gas-liquid chromatography

This chapter discusses the contributions of Dr. Arnoldo Liberti to the development of the technique of chromatography. Dr. Lipsky's involvement in gas chromatography started in 1956. He pioneered in the application of the technique to the analysis of fatty acids and the development of new instrumentation and the new techniques of gas chromatography–mass spectrometry and liquid chromatography. One of his goals has been to split the column effluent before it entered the detector, trap out certain carbon-14 tagged acids, and determine their specific activity. At present, his scientific interests involve the application of advanced chromatographic and spectrometric techniques to certain aspects of the problem of chemical carcinogensis.