Awantika Singh is pursuing her PhD since July, 2011 from CSIR- Central Drug Research Institute, Lucknow and registered in Academy of Scientific and Innovative Research, New Delhi. She is senior research fellow (University Grant Commission, New Delhi) and her topic of research is qualitative and quantitative analysis of Indian medicinal plants and their herbal product using liquid chromatography coupled with tandem mass spectrometry. She has published 11 research articles in the reputed journals.
Berberis species are well known and used extensively as medicinal plants in traditional medicine. They have many medicinal values attributable to the presence of alkaloids having different pharmacological activities. In this study , a method was developed and validated as per international conference on harmonization guidelines using ultra high performance liquid chromatography with hybrid triple quadrupole-linear ion trap mass spectrometry operated in the multiple reaction monitoring mode for nine bioactive compounds, including protoberberine alkaloids, aporphine alkaloids and chlorogenic acid. This method was applied in different plant parts of eight Berberis species to determine variations in content of nine bioactive compounds. The separation was achieved on an ACQUITY UPLC CSH™ C18 column using a gradient mobile phase at flow rate 0.3 mL/min. Calibration curves for all the nine analytes provided optimum linear detector response (with R20.9989) over the concentration range of 0.5–1000 ng/mL. The precision and accuracy of the samples were within RSDs ≤2.4 and ≤2.3%, respectively. The results indicated significant variation in the total contents of the nine compounds in Berberis species. Results indicate that all the nine bioactive compounds are the most abundant in B. petiolaris stem. Chlorogenic acid, magnoflorine and berberine are found abundant in leaf, stem and root part, respectively of all the Berberis species. Results also indicated that the roots of B. lycium, B. koehneana and B. chitria may be used for swapping of B. aristata. This information was lacking in the literature and it could be helpful for better swapping of Berberis species.
Andreja Livk has over 17 years of experience in protein and peptide chemistry, including isolation and characterisation of peptides by RP-HPLC. Her skills include the synthesis of a wide range of peptides including complex bridged peptides. She has also extensively characterised low molecular mass peptides using a wide range of mass spectrometry systems, as well as de novo peptide sequencing for interpretation of MS/MS spectra.
A comprehensive physicochemical characterisation of novel biosimilar products is a prerequisite for their application and manufacturing. A side-by-side analysis, relative to reference products, can provide comparative data for biosimilars and demonstrate their suitability in relation to regulatory requirements. The aim of this study is to determine physicochemical properties of human insulin and its two analogues, aspart and glargine. In the insulin analogues, different amino acid residues are added or substituted at certain positions along the A and B chains to give them special acting characteristics in the human body. Mass spectrometry based peptide mapping, N/C terminal sequencing and intact mass analysis were conducted to determine differences in primary structures of the insulin analogues. Disulphide bond pairing, which is critical for protein’s structure and its function, was performed by online LC/ESI-MS/MS analysis. By mapping the position of each disulphide bond through sequential reduction and alkylation steps, mass spectrometry analysis eliminated downstream functional characterisation issues by confirming that the molecule is folded correctly.