Rapid and One-Step Screening of Taxane Compounds by a Two-Dimensional Carbon Microfiber Fractionation System Combined with Tandem Mass Spectrometry

Fast, sustainable, and simultaneous analysis of water- and fat-soluble vitamins by the two-dimensional microcarbon fiber fractionation system hyphenated with MS detection

BACKGROUND

Vitamins are micronutrients that are required for normal growth and development of living organisms. However, due to their various chemical properties (e.g., acid-base behavior, the presence of numerous forms) and fluctuating concentration levels within complex matrices, simultaneous analysis of multi-class vitamins, including their active forms, is a challenging task. The growing nutrient shortage in foods is concerning for food consumers, manufacturers, and quality control organizations. Hence, a simple, fast, and greener approach that can simultaneously analyze multi-class vitamins is required to aid food testing and clinical laboratories in evaluating vitamin content more rapidly and accurately.

RESULTS

A green and rapid analytical method based on online two-dimensional microscale carbon fiber/activated carbon fiber fractionation-mass spectrometry (2DμCFs-MS) was developed and validated for simultaneous determination of vitamins (water- and fat-soluble vitamins and some analogs) in food supplements and fortified energy drinks. Vitamins have been successfully separated into three different fractions using the minimum toxic solvent (only 0.7 mL of organic solvent) in a single run within 6 min. The limit of detection (LOD) ranges from 0.1 to 10.4 ng/mL, and the limit of quantification (LOQ) ranges from 0.39 to 34.5 ng/mL. The method also showed adequate repeatability and intermediate precision, with RSD<10 % and R2 > 0.99 for most vitamins. The analytical method was evaluated in terms of greenness, with an analytical greenness (AGREE) score of 0.68.

SIGNIFICANCE

The 2DμCFs-MS system was developed to separate and detect multi-class vitamins simultaneously, which can be used as a beneficial tool to investigate vitamin content for food labeling and determining the vitamins in biological fluids and other complex samples. The developed method can tackle the challenge of simultaneous and fast routine analysis of multi-class vitamins.

Use of tandem carbon microfiber columns for on-line fractionation strategy of reducing ion suppression effects in electrospray ionization-mass spectrometry

As we all know, the complexity and diversity of complex sample are confronting with challenge of high-sensitive mass spectrometry analysis, especially direct mass spectrometry. The work proposed a two-dimensional carbon microfiber fractionation (2DμCFs) system for the reduction of ion suppression effects in electrospray ionization mass spectrometry (ESI-MS). The 2DμCFs system can on-line fractionated the complex sample into strong-polar, medium-polar and weak-polar fractions for sequential MS analysis. Direct analysis brings about the strong ion suppression effect up to 85%, but the fractionated analysis of 2DμCFs system can distinctly reduce the ion suppression effect to less than 43%, even close to none. And the fractionated analysis not only decrease the number of analytes of direct analysis, but also narrows down the polarity range of analytes within the droplets of ESI, contributing to the homogeneous distribution to reduce the ion suppression effect. As an example, the 2DμCFs system coupled with tandem mass spectrometry (MS/MS) was applied for fractionated analysis of Radix Puerariae extract in 4.5 min. Compared with direct MS/MS, the 2DμCFs-MS/MS shows the lower ion suppression and the more ionic species (m/z). In addition, and most of ionic species detected by the 2DμCFs-MS/MS, are the same as those by HPLC MS/MS. Furthermore, the 2DμCFs-MS/MS exhibit the good analysis repeatability of real sample with the RSDs less than 10.32% (intra-day), 7.12% (inter-day) and 14.28% (inter-batch of CFs and ACFs). The carbon fibers (CFs) and active carbon fibers (ACFs) columns, as the key parts, are conducive to achieve on-line fractionation of compounds based on the difference of polarity. The 2DμCFs system has the merits of on-line, speediness, low-pressure and recycle. More importantly, such fast and high-throughput method is advantageous for comprehensive screening of complex samples in drug, clinical, environment and plant.