Authors:X. Li, J. Xu, Y. Jiang, L. Chen, Y. Xu, and C. Pan
High-performance liquid chromatography with a hydrophilic-interaction liquid chromatographic (HILIC) column has been successfully used to retain and separate the polar phosphonic herbicides glyphosate and glufosinate. Online electrospray tandem ion-trap mass spectrometric and DAD detection were used. The effects on the separation of mobile phase acetonitrile content, buffer concentration, and flow rate, and of column temperature, were investigated. With UV-visible detection at 195 nm, LOQ were <850 mg kg−1, showing the method is suitable for product quality control of these herbicides alone or in combination. Tandem mass spectrometric conditions were optimized for ion-trap detection. Quantification was by use of selected reaction monitoring transitions m/z 168 → 150 in negative-ion mode for glyphosate and m/z 182 → 136 in positive-ion mode for glufosinate. Limits of detection (LOD; S/N > 3) were 0.20 and 0.16 ng for glyphosate and glufosinate, respectively, and the respective limits of quantification (LOQ; S/N = 10) were 0.02 and 0.05 mg kg−1. Sample derivatization was not necessary to achieve low detection limits in residue analysis in this study. Recovery from watermelon, spinach, potato, tomato, radish-root, and water fortified with the herbicides ranged from 63.6 to 107.3% and relative standard deviations were <15.3%.
Authors:Bhagyashri Kumbhalkar, Shubhada Tamhankar, and Anuradha Upadhye
Bottle gourd (Lagenaria siceraria (Molina) Standl.) is an important vegetable cucurbit cultivated in the warmer parts of the world. Forms bearing nonbitter fruits are used as vegetables, while those with bitter fruits are used in the Indian Traditional System of Medicine. The presence of cucurbitacins is probably the only distinguishing feature between the two forms. The present communication describes the development and validation of a high-performance thin-layer chromatographic (HPTLC)–densitometric method for the estimation of cucurbitacin B in bottle gourd using the International Conference on Harmonization (ICH) guidelines. The complete methanol extracts obtained by accelerated solvent extraction (ASE) were resolved in the mobile phase chloroform– methanol (9.5:0.5, v/v), wherein cucurbitacin B was resolved at RF 0.67 ± 0.02. Linear relationship was obtained between the values 200 and 1200 ng per spot (r = 0.9909). The limit of detection and limit of quantification were 40 and 200 ng per spot, respectively. The recovery of compound varied between 94 and 96%. Using the developed HPTLC method, the cucurbitacin B content in the vegetative parts (VP) and fruits (F) of the bitter form was found to be 0.017% and 0.062%, respectively, while it was not detected in the nonbitter form. The application of the method to study the accumulation of cucurbitacin B during progressive developmental stages of fruits of both forms revealed an increasing content of cucurbitacin B from 0.001 to 0.085% during the fruit development in the bitter form. In investigations of market samples, cucurbitacin B was detected in two out of six samples indicating admixture of bitter and nonbitter forms. To the best of our knowledge, this study is the first report of the evaluation of bitter and nonbitter forms of bottle gourd for cucurbitacin B using HPTLC. The developed method may be applicable in the routine quality control of marketed products and formulations of bottle gourd.
university webdomains are relevant sources, but there are many cases where there is no qualitycontrol not by the scholars or by Google.
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Authors:Sanjay Saxena, Yogendra Kumar, and Ashutosh Dash
An indigenous technology for the production of 125I brachytherapy sources has been developed for the management of intraocular cancer. This indigenous method of producing 125I seeds represents a new paradigm, and a thorough quality evaluation of the seeds in accordance with Atomic Energy Regulatory
Board (AERB) of India was carried to ensure their safety during therapy. In this current work, we describe an overview of
our experience, the efforts made in establishing enviable quality analysis of 125I seeds to ensure their safety in episcleral plaque brachytherapy.
Several chromatographic methods have been used for determining the radiochemical purity of99mTc-phytate. Good separation of99mTc-phytate from radiochemical impurities was performed using gel column chromatography packed with Sephadex G-10. Reduced99mTc-complexes and99mTc-phytate were not separated by paper and thin layer chromatography.
Horseradish samples (
Cochlearis armoracia L.
) and mustard samples (
Sinapis alba L.
) were extracted with 70:30 (
) methanol-water in accordance with ISO method 91671. Samples of commercial mustard with and without horseradish were submitted to the same extraction procedure. Separation of the active compounds from these samples were performed on silica gel 60 plates with preconcentration zone and on silica gel F
high-performance thin-layer chromatography plates, with
-propanol-25% ammonia, 90 + 10 (
), containing different volumes of distilled water (1, 2, 3, or 5 parts), as mobile phases. After development the compounds were visualized in UV light at
= 254 nm or by exposure to iodine vapor.