HPLC-APCI-MS/MS method development and validation for determination of tocotrienols in human breast adipose tissue

Determination of free and bound antioxidants in Kamut® wheat by HPLC with triple detector (DAD-CAD-MS)

Kamut® wheat (Triticum turgidum ssp. turanicum), an ancient, underutilized cereal, offers potential health benefits due to its phenolic compounds. This study aimed to investigate the antioxidant potential of Kamut® wheat's free and bound phenolic extracts using an HPLC system equipped with three detectors. The bound extracts, released after alkaline hydrolysis, exhibited higher total phenolic and flavonoid content compared to the free extracts (p < 0.05). The total antioxidant capacity of bound extracts was six-fold greater than in free extracts (p < 0.05). The main antioxidants in free extracts were tyrosine, phenylalanine, tryptophan, and apigenin. In bound extracts, ferulic acid, its dimers and trimer were present. Kamut® wheat exhibited a source of dietary antioxidants and should be considered a potential ingredient for the development of functional foods. Also, the HPLC-triple detector system is effective for in-depth profiling of antioxidant compounds, paving the way for future research on similar grains.

Rapid Characterization of Drugs in Biological Fluid and Seized Material Using Thermal-Assisted Carbon Fiber Ionization Mass Spectrometry

Developing a rapid, simple, and sensitive method to analyze drugs is critical to forensic research study because of the widespread occurrence of the matrix effect. Herein, we develop a method using thermal-assisted carbon fiber ionization mass spectrometry that can be used to directly analyze drugs in biological fluid. The key feature of this technique is that the biological samples such as urine and blood can be achieved online as precipitated protein on the carbon fiber tip and thermally desorbed by the metal ceramics heater, which can reduce the matrix effects and improve the sensitivity. Analytes including raw urine, blood, oral fluid, drink, tobacco tar, drug tablets, and paper cards can be rapidly identified and analyzed within a few minutes regardless of their physical variations. Due to its simplicity and noninvasive analysis, this method can be used for drugged driving analysis and to achieve point-of-care drug testing in clinical and forensic chemistry.

Optimization and application of high-throughput supported liquid extraction for simultaneous determination of carotenoids and fat-soluble vitamins in serum

The demand for analysis of carotenoids (CAR) and fat-soluble vitamins (FSV) is continuously expanding, but currently used sample preparation methods either require complicated extraction procedure or large sample volume, let alone the reliability of the results. This study aimed to develop a fast, high-efficient, and high-throughput method based on supported liquid extraction (SLE) for the simultaneous extraction of FSV and CAR from human serum before using high-performance liquid chromatography-diode array detector (HPLC-DAD) analysis. The optimization of SLE parameters was achieved through response surface methodology (RSM) based on the Box-Behnken design (BBD) and included serum-water-extraction solvent ratio and eluent volume. Under optimal conditions, the proposed method gives acceptable limits of detection (LOD) (0.005-0.3 μg/mL), good recovery (89.6-110.9%) as well as relative standard deviation (RSD) of less than 10.1% by consuming lower serum sample (100 μL) and less sample preparation time (2 min per sample). Compared with liquid-phase extraction (LLE), the SLE delivers rapid extraction with higher recovery, better reproducibility, and lower matrix effect for CAR and FSV analysis. The method has been successfully applied to quantify CAR and FSV levels in serum of healthy individuals and age-related macular degeneration (AMD) patients, demonstrating the feasibility of the proposed method for epidemiology and routine applications.

Tocotrienols and Cancer: From the State of the Art to Promising Novel Patents

BACKGROUND

Tocotrienols (TTs) are vitamin E derivatives naturally occurring in several plants and vegetable oils. Like Tocopherols (TPs), they comprise four isoforms, α, β, γ and δ, but unlike TPs, they present an unsaturated isoprenoid chain. Recent studies indicate that TTs provide important health benefits, including neuroprotective, anti-inflammatory, anti-oxidant, cholesterol lowering and immunomodulatory effects. Moreover, they have been found to possess unique anti-cancer properties.

OBJECTIVE

The purpose of this review is to present an overview of the state of the art of TTs role in cancer prevention and treatment, as well as to describe recent patents proposing new methods for TTs isolation, chemical modification and use in cancer prevention and/or therapy.

METHODS

Recent literature and patents focusing on TTs anti-cancer applications have been identified and reviewed, with special regard to their scientific impact and novelty.

RESULTS

TTs have demonstrated significant anti-cancer activity in multiple tumor types, both in vitro and in vivo. Furthermore, they have shown synergistic effects when given in combination with standard anti-cancer agents or other anti-tumor natural compounds. Finally, new purification processes and transgenic sources have been designed in order to improve TTs production, and novel TTs formulations and synthetic derivatives have been developed to enhance their solubility and bioavailability.

CONCLUSION

The promising anti-cancer effects shown by TTs in several preclinical studies may open new opportunities for therapeutic interventions in different tumors. Thus, clinical trials aimed at confirming TTs chemopreventive and tumor-suppressing activity, particularly in combination with standard therapies, are urgently needed.

Determination of tocopherols and tocotrienols in human breast adipose tissue with the use of high performance liquid chromatography-fluorescence detection

Tocopherols and tocotrienols have been extensively studied owing to their anticancer potential, especially against breast cancer. Therefore, the aim of this study was to quantitatively determine tocochromanols in human breast adipose tissue with the use of HPLC-FLD. The sample preparation procedure included homogenization and solvent extraction with isopropanol-ethanol-0.1% formic acid mixture prior to solid-phase extraction. After implementation of central composite design, satisfactory separation of all eight target compounds was achieved within 10.5 min. Chromatographic runs were carried out with the use of a naphthylethyl chromatographic column with methanol-water mixture (89:11, v/v) as the mobile phase. Fluorescence detection of tocochromanols was performed with excitation and emission wavelengths 298 and 330 nm, respectively. The method was validated in terms of linearity, carryover, recovery, precision, accuracy and stability. Extraction yield was also determined for accurate evaluation of vitamin E content in human breast adipose tissue samples. Finally, concentrations of particular tocochromanols compounds were assessed in human breast adipose tissue samples obtained from 99 patients, including women with breast cancer, healthy volunteers and deceased women who had died as a result of accidents. The raw data was transformed according to the newly developed equation for accurate estimation of the concentrations of tocochromanols in breast adipose tissue samples. Results obtained in the study indicated that the proposed analytical assay could be useful in breast cancer research.

Ionization of tocopherols and tocotrienols in atmospheric pressure chemical ionization

RATIONALE

Tocopherols and tocotrienols are chemical compounds insusceptible to the ionization process under atmospheric pressure conditions. Therefore, the selection of the optimal ion source settings for their quantification requires special attention. The aim of this study was to analyse the influence of the APCI source parameters on the response of tocochromanols and two related compounds.

METHODS

Standard solutions of target compounds were injected on the high-performance liquid chromatography/atmospheric pressure chemical ionization tandem mass spectrometry (HPLC/APCI-MS/MS) system separately and analysed with 30 randomly selected ion source settings. The obtained responses were modelled by multivariate linear regression with least absolute shrinkage and selection operator. The developed models were used to choose the best APCI conditions.

RESULTS

Multivariate linear models were built for eight tocochromanols, trolox and BHT. The APCI settings derived from the models did not increase the peak areas obtained for T and T3 during the ionization process. Ionization conditions based on models for trolox and BHT improved analytical responses by 12-36% and 4-32%, respectively. The application of the ion source settings optimal for trolox and BHT to tocochromanols did not result in better analytical responses.

CONCLUSIONS

The ionization pattern of tocochromanols in the APCI source is problematic and should be further investigated. Modelling methodology for response improvement presented in this study can be applied in similar studies.