Chemical Fingerprinting of Valeriana Species: Simultaneous Determination of Valerenic Acids, Flavonoids, and Phenylpropanoids Using Liquid Chromatography with Ultraviolet Detection

Abstract The roots and rhizomes of various valeriana species are currently used as a sleeping aid or mild sedative. A liquid chromatography method has been developed that permits the analysis of chlorogenic acid, lignans, flavonoids, valerenic acids, and valpotrates in various valerian samples. The best results were obtained with a Phenomenex Luna C18(2) column using gradient elution with a mobile phase consisting of water and 0.05% phosphoric acid and 2100% acetonitrilemethanol (1 + 1) with 0.05% phosphoric acid. The flow rate was 0.8 mL/min and ultraviolet detection was at 207, 225, 254, 280, and 325 nm. Different valerian species and commercial products showed remarkable quantitative variations. Chlorogenic acid (0.21.2%), 3 lignans, linarin (0.0020.24%), and valepotriates were detected in all the valeriana species analyzed. Highest amounts of valerenic acids were detected in V. officinalis L., trace amounts in V. sitchensis, and none in the other species analyzed.

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Determination of Chlorotetracycline and Doxycycline in Medicated Feedingstuffs by Liquid Chromatography

Bulletin of the Veterinary Institute in Pulawy ◽

10.2478/v10213-012-0058-5 ◽

2012 ◽

Vol 56 (3) ◽

pp. 329-333 ◽

Cited By ~ 3

Author(s):

Ewelina Patyra ◽

Ewelina Kowalczyk ◽

Krzysztof Kwiatek

Keyword(s):

Liquid Chromatography ◽

High Performance ◽

Analytical Procedure ◽

Solid Phase ◽

Gradient Elution ◽

Diode Array ◽

Chromatography Method ◽

Array Detection ◽

Liquid Chromatography Method

Abstract High performance liquid chromatography method with diode array detection (HPLC-DAD) was developed and optimised for the determination of tetracyclines (TCs) in medicated feedingstuffs. The extraction of the analyte from feedingstuffs was performed with Na2EDTA-McIlvaine buffer (pH 2.5 and pH 4). The extracts were cleaned up by solid phase extraction using octadecyl cartridges (C18). The samples were dried up and redissolved in the mixture of oxalic acid and methanol. Separation was performed on reserved phase column (Phenomenex C18, 250 x 4.6 mm, 5 μm) by multistep gradient elution, which provided better chromatographic separation. The analysis was performed at a wavelength of 390 nm. Validation study of the method revealed that all obtained calibration curves showed good linearity R= 0.9985 for doxycycline (DC) and R= 0.9981 for chlorotetracycline (CTC) over the range of 25-2,000 mg/kg. The analytical procedure was successfully adapted for quantitative determination of DC and CTC in medicated feedingstuff samples. Validation included determination of specificity, linearity, and repeatability. Mean recovery for spiked samples was 93.1% for CTC and 93.2% for DC. The results of validation of the analytical procedure proved that presented method is efficient, precise and useful for quantification of DC and CTC in medicated feedingstuffs.

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High-performance liquid chromatography method for the simultaneous determination of thiamine hydrochloride, pyridoxine hydrochloride and cyanocobalamin in pharmaceutical formulations using coulometric electrochemical and ultraviolet detection

Journal of Chromatography A ◽

10.1016/j.chroma.2005.07.091 ◽

2005 ◽

Vol 1094 (1-2) ◽

pp. 91-98 ◽

Cited By ~ 53

Author(s):

Marcin Leszek Marszałł ◽

Anna Lebiedzińska ◽

Wojciech Czarnowski ◽

Piotr Szefer

Keyword(s):

High Performance Liquid Chromatography ◽

Liquid Chromatography ◽

High Performance ◽

Pharmaceutical Formulations ◽

Thiamine Hydrochloride ◽

Pyridoxine Hydrochloride ◽

Chromatography Method ◽

Ultraviolet Detection ◽

Liquid Chromatography Method

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Forced degradation studies and stability-indicating liquid chromatography method for determination of tirofiban hydrochloride and synthetic impurities

Revista Colombiana de Ciencias Químico Farmacéuticas ◽

10.15446/rcciquifa.v49n2.89926 ◽

2020 ◽

Vol 49 (2) ◽

Author(s):

Adriane Lettnin Roll Feijó ◽

Fernanda Macke Hellwig ◽

Clésio Soldateli Paim ◽

Marcelo Donadel Malesuik

Keyword(s):

Liquid Chromatography ◽

Degradation Products ◽

Gradient Elution ◽

Pharmaceutical Products ◽

Raw Material ◽

Forced Degradation ◽

Chromatography Method ◽

Stability Indicating ◽

Liquid Chromatography Method

This study aimed to develop and validate a stability-indicating liquid chromatography method for the determination of tirofiban hydrochloride and two synthetic impurities (impurity A and impurity C). The method utilizes a RP-18 column (250 mm × 4.6 mm; 5 μm) with the PDA detector for quantitation. A mixture of triethylamine 0.1% (acidified to pH 5.5 with phosphoric acid) and acetonitrile was used as the mobile phase at a flow rate of 1 mL min−1 with gradient elution. The method presented satisfactory linearity, precision, accuracy and robustness, as well as low limits of detection and quantification, which demonstrate sensitivity in the determination of tirofiban and impurities A and C. It was selective for the determination of the drug and impurities analysed, without interference of the degradation products generated under forced conditions, demonstrating the stability-indicating capacity of the proposed method. Tirofiban showed to be practically stable to oxidative (30% H2O2 for 24 h) and thermal (75 ºC for 24 h) conditions, but presented degradation to UVA light and acid hydrolysis, obeying the first order kinetics for both. In this way, it can be used as a stability-indicating method in the quality control of the raw material of tirofiban hydrochloride, as well as of the finished product. The obtained results demonstrate the importance of deepening the studies in this area, in order to guarantee the quality of commercialized pharmaceutical products.

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