Simultaneous analysis of heparosan oligosaccharides by isocratic liquid chromatography with charged aerosol detection/mass spectrometry

Spectrum-Effect Relationship in Chinese Herbal Medicine: Current Status and Future Perspectives

The quality of Chinese herbal medicine (CHM) directly impacts clinical efficacy and safety. Fingerprint technology is an internationally recognized method for evaluating the quality of CHM. However, the existing quality evaluation models based on fingerprint technology have blocked the ability to assess the internal quality of CHM and cannot comprehensively reflect the correlation between pharmacodynamic information and active constituents. Through mathematical methods, a connection between the "Spectrum" (fingerprint) and the "Effect" (pharmacodynamic data) was established to conduct a spectrum-effect relationship (SER) of CHM to unravel the active component information associated with the pharmacodynamic activity. Consequently, SER can efficiently address the limitations of the segmentation of chemical components and pharmacodynamic effect in CHM and further improve the quality evaluation of CHM. This review focuses on the recent research progress of SER in the field of CHM, including the establishment of fingerprint, the selection of data analysis methods, and their recent applications in the field of CHM. Various advanced fingerprint techniques are introduced, followed by the data analysis methods used in recent years are summarized. Finally, the applications of SER based on different research subjects are described in detail. In addition, the advantages of combining SER with other data are discussed through practical applications, and the research on SER is summarized and prospected. This review proves the validity and development potential of the SER and provides a reference for the development and application of quality evaluation methods for CHM.

Alternative methods to assess the impurity profile of a monographed API using acarbose as an example

Even though the impurity analysis of the Ph. Eur. is considered well-studied, its methodology should be reviewed periodically to ensure that it is working properly, and all impurities are captured by the section "Related substances" of the monograph. Within this study, the biotechnological produced antidiabetic drug acarbose was chosen to demonstrate some of the advantages as well as the shortcomings arising from the current related substances test of acarbose. Due to its weak chromophore, acarbose is studied by UV detection at 210 nm after being separated on aminopropyl-silyl stationary phases. Thus, the use of alternative detection techniques, such as charge aerosol detection (CAD) and a volatile mobile phase can be beneficial here. Since a simple method transfer to a mobile phase usable with the CAD was not possible, more stable stationary phases were tested. For the rapid determination of the sum of impurities, a method was developed using a pentafluorophenyl column and a mobile phase of 0.1% TFA in water. Maltose and maltotriose were further identified as additional impurities of the API. Furthermore, a method was developed and validated by means of an Amide-HILIC phase, that adequately separated acarbose and all of its impurities. However, the sensitivity of this method needs to be further improved. Additionally, a method was also developed and validated, taking into account the temperature stability of graphite columns. Thus, the separation was carried out at temperatures of about 90 °C to solve the problem of anomerization of acarbose and some of its impurities. In comparison with the other developed methods, the elution order was changed and has to be confirmed, but all components were separated and detected at a sufficient LOQ of 0.10%.

Hydrophilic Interaction Chromatography Coupled with Charged Aerosol Detection for Simultaneous Quantitation of Carbohydrates, Polyols and Ions in Food and Beverages

Here, we report an accurate and versatile method for the simultaneous determination of 17 sugars (arabinose, erythrose, fructose, galactose, glucose, isomaltulose, lactose, lyxose, maltose, maltotriose, mannose, raffinose, rhamnose, ribose, sucrose, sorbose and xylose), seven polyols (erythritol, inositol, lactitol, maltitol, mannitol, sorbitol and xylitol), five ions (K⁺, Br⁻, Cl⁻, NO³⁻ and SO₄²⁻) and the pseudosaccharide acarbose. For compound separation, hydrophilic interaction chromatography (HILIC) coupled to a corona charged aerosol detector (CAD) was used. The method was validated for linearity, precision, reproducibility, retention factor and optimal injection volume. Standards were measured in the range of 1–1000 mg L⁻¹ and showed good intraday and interday repeatability, as well as precision (relative standard deviation (RSD) < 5%). The LODs and LOQs for the 30 analytes were in the range of 0.032–2.675 mg L⁻¹ and 0.107–8.918 mg L⁻¹, respectively. This method exhibited correlation coefficients of at least R² > 0.97 for all analytes. The method was tested in 24 food and beverage samples to validate the separation efficiency and sensitivity in natural food matrices and to show the practicability of its use for routine food analysis.