Su Zhang (Presenter)
California Department of Public Health
Bio: I work for Shanghai Institute for Food and Drug Control. I dedicated most of my time in the quality standards development work, current quality standard upgrading for Traditional Chinese Medicine(TCM). I also undertake the inspection of the illegal Chemicals addition in healthcare products, TCM and natural products by means of LC-MS since 2005. After I came to US, I work on Q-exactive about discovery of unknown pollutants metabolites in urine. Ć
Authorship: Su Zhang*, Dandan Chen, Hong Yu, Jianwen She, Shen Ji
California Department of Public Health, Environmental Health Laboratory Branch, Biochemistry Section, 850 Marina Bay Parkway, Richmond, CA 94804
| Short Abstract It is difficult to separate, qualify and quantitate amino acids in complex matrix. A reliable method using UPLC/Q-tof-MS coupled with AQC pre-column derivatization was established to determine amino acids in Huangqi injection ( a traditional Chinese injection) and its intermediates. AQC derivatization¡¦s product could be analyzed by MS in ESI mode which is superior to UV detection used in other methods. Furthermore, the accurate mass analysis of Q-tof facilitates the identification of unknown amino acids in Huangqi injection. The method provides good separation, reliable qualification and quantification of 19 amino acids in complex matrices. |
Long Abstract
Amino acids widely exist in nature and are highly active components in many Chinese herb medicine. However, their analysis is still a challenge especially in complex matrix like Chinese herb medicine. The common methods to analysis amino acids are either a direct analysis with HPLC- tandem MS or HPLC ¡VUV with pre-column derivatization. First approach may not provide good separation and the second one lacks of the confirmation capability.
We established an UHPLC/Q-tof-MS method coupled with AQC pre-column derivatization to monitor the quality of Huangqi Injection. The pre-column derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) offers following advantages for amino acids analysis. First, stable and convenient AQC derivatization products result in more efficient reversed phase UHPLC separation with an average peak width of 0.1 min and the total retention time of 10 min. for 19 amino acids (Figure 1). Second, AQC derivatization products are compatible with MS system. We developed a method to analyze AQC derivatization products of amino acids in ESI - Q-tof MS. The accurate mass of Q-tof make the structure identification and confirmation easier compared with the unit mass resolution MS. With this new method, we were able to identify two additional amino acids ( GABA and Asp ) without standards. By comparing the accurate mass of the fragments with literature date, their structures were confirmed. The efficient separation from AQC derivatization and accurate mass determination from Q-tof make amino acids analysis possible in Huangqi injection when not all the standards are available. Ninteen amino acids presented in Huangqi injection are listed in Table 1.
An Agilent 1290 Infinity UHPLC with a BEH-C18 Column (2.1mm¡Ñ150mm,3.5µm), connected with Agilent 6550 iFunnel Q-tof was used for the analysis and the derivatization agent is Waters AccQ-Tag. The procedure is very simple: fill the vial with Huangqi injection and set up the procedure of derivatization in sample module. The derived samples is separated by the column in UHPLC and analyzed by Q-tof MS for qualification and quantitation purposes. Details of testing method and its performance will be presented.
References & Acknowledgements:
Luke Gwatidzo, Ben M. Botha, Rob I. McCrindle. Determination of amino acid contents of manketti seeds (Schinziophyton rautanenii) by pre-column derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate and RP-HPLC [J]. Food Chemistry, 2013, 141(3),2163-2169.
| Description | Y/N | Source |
| Grants | no | |
| Salary | no | |
| Board Member | no | |
| Stock | no | |
| Expenses | no |
IP Royalty: no
| Planning to mention or discuss specific products or technology of the company(ies) listed above: | no |