Simultaneous determination of seven lignans in Justicia procumbens by high performance liquid chromatography-photodiode array detection using relative response factors.

A simple and sensitive HPLC coupled with photodiode array (HPLC-PDA) method was developed for simultaneous determination of seven lignans in Justicia procumbens using relative response factors (RRFs). The chromatographic separation was performed on a Shiseido Capcell Pak C(18) column (250 × 4.6 mm id, 5 µm), a gradient elution of acetonitrile/water, and a photodiode array detector. The column temperature was maintained at 35°C and the detection wavelength was set at 256 nm. Chinensinaphthol methyl ether was selected as the reference compound for calculating the relative response factors of the lignans. It has shown that the RRFs for lignans are quite similar at 256 nm of detection under different analytical conditions (different columns and HPLC instruments). Using RRFs, not every lignan is needed as a reference standard, making the method ideal for rapid, routine analysis, especially for those laboratories where lignans standards are not readily available. An economic and practicable HPLC method using RRFs was established for the determination of seven lignans in J. procumbens. This method not only can determine multiple indexes in traditional Chinese medicines (TCMs) simultaneously, but also resolve the problem of lacking of chemical standards. It will be a good quality evaluation method and pattern for TCMs.

[Simultaneous determination of aflatoxin B1, B2, G1, G2 and ochratoxin A in Glycyrrhiza uralensis by HPLC-fLD after immunoaffinity column with online post-column photochemical derivatization].

OBJECTIVE: To develop a method for the simultaneous determination of aflatoxin B1, B2, G1, G2 and ochratoxin A in Glycyrrhiza uralensis by HPLC-FLD after immunoaffinity column with online post-column photochemical derivatization. METHOD: Sample was extracted with MeOH: H2O (80:20) and cleaned up by immunoaffinity column. The toxins were separated by reversed-phase HPLC and the mobile phase was consisted of methanol and 0.5% acetic acid solution with gradient elution. The determination was carried out by fluorescence detector after photochemical derivatization. RESULT: The detection limits of aflatoxin G2, G1, B2, B1 and ochratoxin A were 0.02, 0.06, 0.015, 0.03 and 0.25 microg x kg(-1), respectively. The recoveries of analytes were from 76.0% to 103% and the relative standard deviations (RSDs) were below 13%. CONCLUSION: The method is a simple, accurate and can be used to determine the contents of aflatoxin B1, B2, G1, G2 and ochratoxin A in G. uralensis simultaneously.

Ultrasonic-assisted liquid-liquid extraction and HILIC-ELSD analysis of ginsenoside Rb(1), astragaloside IV and dulcitol in sugar-free "Fufangfufangteng Heji".

A simple method for the extraction and determination of ginsenoside Rb(1), astragaloside IV and dulcitol in sugar-free "Fufangfufangteng Heji" was developed using an ultrasonic-assisted liquid-liquid extraction (UALLE) coupled with Hydrophilic Interaction Liquid Interface Chromatography and Evaporative Light Scattering Detector (HILIC-ELSD) analysis. Good chromatographic separation was achieved using a Phenomenex Luna HILIC column (250mm×4.6mm i.d., 5µm), and a mobile phase consisting of acetonitrile-water at a flow rate of 1.0ml/min with a gradient elution within 25min was also used. Compared to the conventional analysis method, the proposed method had the advantages of a longer column life, shorter analysis time, lower baseline noise, short sample pretreatment time and low consumption of organic solvent. The linear ranges for ginsenoside Rb(1), astragaloside IV and dulcitol were 0.0256-0.179, 0.110-0.770, 0.105-0.630mg/ml, respectively. The recoveries of ginsenoside Rb(1), astragaloside IV and dulcitol during the pharmaceutical preparation were within the range of 97.2-100.3%, and their relative standard deviations were 1.2-3.1%.

[Quantitative determination of pinoresinol diglucoside in Eucommiae unloads by NIRS].

OBJECTIVE: To establish a rapid determination method of pinoresinol diglucoside in Eucommiae unloads by near-infrared reflectance spectroscopy (NIRS). METHOD: Forty-one samples of E. unloads were collected from three different producing areas and their main component, namely pinoresinol diglucoside, was determined by HPLC. Corresponding data of samples were collected from 12 000 to 4 000 cm(-1) by near-infrared reflectance spectroscopy. The spectral pretreatment was optimized by OPUS software and the calibration equations between the content of pinoresinol diglucoside and spectrum data were constructed by partial least squares regression. RESULT: Available information could be extracted from spectra in the range from 7 502 to 4 597.6 cm(-1) after corrected by applying second derivative transformation and subtract a linear correction. Cross validation was used to prevent over-fitting. Good correlation existed between pinoresinol diglucoside content and NIR spectra ( R2 = 0.926 4, SEC = 0.029 and SEP = 0.066 2). CONCLUSION: NIRS calibration equations developed in this study could be applied to the rapid analysis of the pinoresinol diglucoside content.

[Application of HPLC fingerprint in quality control of Fufangteng combination formula].

OBJECTIVE: To establish the characteristic mode of HPLC fingerprint of Fufangteng combination formula for the quality control of this medicine. METHOD: 10 batch certified products were selected to establish the characteristic mode of HPLC fingerprint of Fufangteng combination formula by chromatographic pattern matching and retention time correction. RESULT: This characteristic mode of HPLC fingerprint can clearly differentiate the eligible Fufangteng products from the unqualified products. CONCLUSION: This method can provide thorough information for the quality control of Fufangteng combination formula.