Qualitative and quantitative analysis of flavonoids in Chinese hawthorn fruit / 中国中药杂志

<p><b>OBJECTIVE</b>To develop an LC-MS method for identification of flavonoids in Chinese hawthorn fruits and an HPLC method for quantification of 5 flavonoids.</p><p><b>METHOD</b>Accurate molecular weights of the target flavonoids were acquired by time-of-flight mass spectrometer (TOF-MS) in both positive and negative ion modes. The flavoniods were then further confirmed by standards. An RP-HPLC method was established to quantitatively analysis five major flavonoids (chlorogenic acid, procyanidin B2, epicatechin, hyperoside and isoquercitrin) in hawthorn fruits from ten different regions.</p><p><b>RESULTS</b>The molecular formulae of 8 components were determined by TOF-MS. In the quantitative method validation, the method is linear over the studied range of 1.8-178.5, 2.2-284.8, 2.7-270. 6,1.5-150.0, 1.5-150.0 mg x L(-1) for chlorogenic acid, procyanidin B2, epicatechin, hyperoside and isoquercitrin, respectively. The correlation coefficient for each analyze was greater than 0.999. The inter-day precision of the analysis was lower than 4%, The RSDs of precision and stability were lower than 5%. The recovery rate was from 98.5% to 102.5%, and RSDs were less than 3.5%.</p><p><b>CONCLUSION</b>The method is simple, specific and reliable, and is suitable for quality control of Chinese hawthorn.</p>

Voltammetric determination of salvianolic acid B with a carbon nanotube paste electrode / 中成药

AIM:A voltammetric method was developed for the determination of salvianolic acid B using a carbon nanotube paste electrode.And the separation process of salvianolic acid B was detected. METHODS: In Britton-Robinson buffer solution of pH(1.81),the square wave stripping voltammetric method was used to determine salvianolic acid B. RESULTS: The proposed method was verified by an established HPLC method,and it was applied to determining salvianolic acid B in eluent of eluting extracts of Radix salvia Miltiorrhiza from SP-207 colunm with ethanol solution,and the results were satisfied. CONCLUSION: A new method for determining salvianolic acid B was developed,and the proposed method would be used as an on-line quality control method for detecting of salvianolic acid B in eluting extracts of Radix salvia Miltiorrhiza in the future.