HA-C@silica sorbent for simultaneous extraction and clean-up of steroids in human plasma followed by HPLC-MS/MS multiclass determination

Comprehensive targeted profiling of multiple steroid classes in rodent plasma using liquid chromatography-mass spectrometry

BACKGROUND

Reliable quantification of multiple steroid classes in biological fluids within a single method remains an analytical challenge despite many previously published methods. Crosstalk of positional isomers, overlap of stereoisomer fragmentation patterns, differing proton affinities, in-source fragmentation, varying stability of protonated ions in the gas phase across steroid classes, and non-existence of steroid-free matrix are the main challenges limiting the number of simultaneously profiled steroids.

RESULTS

In this study, we focused on the development of a derivatization-free, achiral, high-throughput, and cost-effective UHPLC-MS/MS approach that allows simultaneous profiling of a spectrum of 38 steroids covering progestogens, androgens, corticosteroids, and estrogens, while properly addressing the hurdles of steroid analysis. Within a 20-min method, 16 stereoisomers and 15 positional isomers were fully resolved within a single run while separated from 7 additional non-interfering steroids and matrix interferences in rodent plasma. Protein precipitation (PP) and supported liquid extraction (SLE) methods using only 40 μL of sample were developed to achieve the lowest possible limits of quantification. Nevertheless, 5α-dihydroprogesterone and 3α,5α-THDOC could be only qualitatively assessed when using PP. In contrast, DHEA-S could not be quantified or identified when using SLE. A novel surrogate matrix-background subtraction approach, using rat plasma after the animal's adrenalectomy, has been implemented into the optimized PP-UHPLC-MS/MS workflow, successfully validated according to the unified ICH/EMA M10 guidelines, and compared to the traditional quantification strategies. Moreover, the validity of the newly adopted approach has been verified by the targeted profiling of multiple biologically active endogenous steroids in more than 500 samples of mouse plasma in total.

SIGNIFICANCE

Underestimation of hurdles associated with steroid analysis often compromises the accurate steroid quantification. Our comprehensive, fully validated UHPLC-MS/MS method targeting a wide spectrum of endogenous steroids, mitigating steroid crosstalk and using a minimal sample volume together with a novel surrogate matrix-background subtraction approach significantly advances steroid analysis for research and clinical applications covering multiple biological scopes.

Biochar-based polymeric film as sustainable and efficient sorptive phase for preconcentration of steroid hormones in environmental waters and wastewaters

BACKGROUND

The environmental impact of sample preparation should be minimized through simplification of the procedures and the use of natural, renewable and/or reusable materials. In such scenario, thin-film microextraction fulfils the former criteria, as it enables few steps and miniaturization, thus small amount of extraction phase. At the same time, the use of sorbents such as biochars obtained from biomass waste is even more promoted due to their availability at low cost and increased life-cycle in a circular economy vision. However, it is not always easy to combine these criteria in sample preparation.

RESULTS

A thin film microextraction was developed for the determination of steroids in aqueous samples, entailing a membrane made of cellulose triacetate and a wood-derived biochar (Nuchar®) as carbon precursor. Different characterization techniques showed the successful preparation, whereas the sorption kinetics experiments demonstrated that biochar is responsible for the extraction with the polymer acting as a smart support. After a study about membranes' composition in terms of biochar amounts (4 %, 10 %, 16 % wt) and type of synthesis set up, the ceramic 3D-mold was selected, achieving reproducible and ready-to-use membranes with composition fixed as 10 %. Different elution conditions, viz. type and time of agitation, type, composition and volume of eluent, were evaluated. The final microextraction followed by HPLC-MS/MS quantification was successfully validated in river and wastewater treatment plant effluent samples in terms of accuracy (R% 64-123 %, RSD<19 % in river; R% 61-118 %, RSD <18 % in effluent, n = 4), sensitivity (MQLs 0.2-8.5 ng L-1) and robustness.

SIGNIFICANCE

This novel biochar-based polymeric film proved to be a valid and sustainable sorbent, in terms of extraction capability, ease of preparation and greenness. By comparison with literature and the greenness evaluation with the most recent metric tools, this method expands the potential applicability of the thin-film microextraction and opens up innovative scenarios for sustainable procedures entailing the use of biochars entrapped in bio-polymers.

Advancing herbal medicine: enhancing product quality and safety through robust quality control practices

This manuscript provides an in-depth review of the significance of quality control in herbal medication products, focusing on its role in maintaining efficiency and safety. With a historical foundation in traditional medicine systems, herbal remedies have gained widespread popularity as natural alternatives to conventional treatments. However, the increasing demand for these products necessitates stringent quality control measures to ensure consistency and safety. This comprehensive review explores the importance of quality control methods in monitoring various aspects of herbal product development, manufacturing, and distribution. Emphasizing the need for standardized processes, the manuscript delves into the detection and prevention of contaminants, the authentication of herbal ingredients, and the adherence to regulatory standards. Additionally, it highlights the integration of traditional knowledge and modern scientific approaches in achieving optimal quality control outcomes. By emphasizing the role of quality control in herbal medicine, this manuscript contributes to promoting consumer trust, safeguarding public health, and fostering the responsible use of herbal medication products.

A new approach of magnetic field application in miniaturized pipette-tip extraction for trace analysis of four synthetic hormones in breast milk samples

Herein, a novel homemade electrical device was designed, including two pieces of external neodymium magnets, providing a reciprocating magnetic field to introduce a magnetic-assisted dispersive pipette-tip micro solid-phase extraction. To evaluate the performance efficiency of the proposed method, a novel magnetic calcined GO/SiO₂@Co-Fe nanocube sorbent was synthesized, filled into the pipette-tip, exposed to the reciprocating magnetic field, and applied for the preconcentration of some hormone therapy drugs in human biological matrices. The effective adsorption and desorption parameters were optimized using a rotatable central composite design and one-variable-at-a-time approaches. Under the optimized conditions, the target analytes' detection limits were found to be below 0.02 ng mL^-1. Moreover, the calibration curves were linear in the range of 0.03-500.00 ng mL^-1 (R² > 0.9966), with RSDs% less than 7.8 %. Eventually, the established method was applied to extract the analytes from breast milk samples, followed by LC-ESI-MS/MS analysis.

From polyethylene waste bottles to UIO-66 (Zr) for preconcentration of steroid hormones from river water

Metal-organic framework (UiO-66 (Zr) was synthesized using polyethylene terephthalate (PET) and used as an adsorbent for extraction and preconcentration of steroid hormones in river water. Polyethylene waste bottles were used as the source of polyethylene terephthalate (PET) ligands. The UIO-66(Zr), which the PET was made from recycled waste plastics, was used for the first time for the extraction and preconcentration of four different types of steroid hormones in river water samples. Various analytical characterization techniques were employed to characterize the synthesized material. The steroid hormones were detected and quantified using high-performance liquid chromatography coupled with diode array detector (HPLC-DAD). The results were further validated using ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Experimental variables, such as sample pH, the mass of adsorbent and extraction time, were optimized using Box-Behnken design (BBD). The dispersive solid phase extraction method combined with HPLC-DAD, displayed good linearity (0.004-1000 µg/L) low limits of detections (LODs, 1.1-16 ng/L for ultrapure water and 2.6-5.3 ng/L for river water) and limits of quantification (LOQs, 3.7-5.3 ng/L for ultrapure water and 8.7-11.0 ng/L for river water samples) and acceptable extraction recoveries (86-101%). The intraday (n = 10) and interday (n = 5) precisions expressed in terms of relative standard deviations (%RSD) were all less than 5%. The steroid hormones were detected in most of the river water samples (Vaal River and Rietspruit River). The DSPE/HPLC method offered a promising approach for simultaneous extraction, preconcentration and determination of steroid hormones in water.

Multiclass ultrasound-assisted extraction, clean-up and high performance liquid chromatography-tandem mass spectrometry quantification of steroid hormone residues in compost

An analytical method for multiclass determination of steroid hormones in compost has been developed to fill the lack of methods for steroid residuals monitoring in this waste-derived product, increasingly produced and recycled in the circular-economy approach. The procedure simply entails an ultrasound-assisted extraction (UAE) on 300 mg compost by 3 × 2.5 mL methanol × 5 min sonication steps followed by a quick clean-up by solid-phase extraction (SPE) on the silica-based Supelclean™ LC-NH₂ that avoids use of organic solvents. The clean extract is analysed by HPLC-MS/MS achieving firm identification and quantitation of the 16 steroids, i.e., glucocorticoids, progestins, androgens, oestrogens. The analytical figures of merits were assessed, viz. selectivity, sensitivity, linearity, matrix effect, trueness, precision, carry-over and robustness, in line with updated guidelines. Recovery was investigated in the concentration range 15-800 ng g^-1, and at the quality control levels (15, 50, 200 and 400 ng g^-1) was in the range 60-120%, with inter-day precision RSDs < 20% (n = 3). The experimental quantification limit was 15 ng g^-1 for all the hormones. The method was applied to analysis of different compost samples proving to be functional to environmental monitoring.

A New Heart-Cutting Method for a Multiplex Quantitative Analysis of Steroid Hormones in Plasma Using 2D-LC/MS/MS Technique

The aim of the current research was to develop a simple and rapid mass spectrometry-based assay for the determination of 15 steroid hormones in human plasma in a single run, which would be suitable for a routine practice setting. For this purpose, we designed a procedure based on the 2D-liquid chromatography-tandem mass spectrometry with a minimalistic sample pre-treatment. In our arrangement, the preparation of one sample takes only 10 min and can accommodate 40 samples per hour when tested in series. The following analytical run is 18 min long for all steroid hormones. In addition, we developed an independent analytical run for estradiol, significantly increasing the assay accuracy while taking an additional 10 min to perform an analytical run of a sample. The optimized method was applied to a set of human plasma samples, including chylous. Our results indicate the linearity of the method for all steroid hormones with squared regression coefficients R2 ≥ 0.995, within-run and between-run precision (RSD < 6.4%), and an accuracy of 92.9% to 106.2%. The absolute recovery for each analyzed steroid hormone ranged between 101.6% and 116.5%. The method detection limit for 15 steroid hormones ranged between 0.008 nmol/L (2.88 pg/mL) for aldosterone and 0.873 nmol/L (0.252 ng/mL) for DHEA. For all the analytes, the lowest calibration point relative standard deviation was less than 10.8%, indicating a good precision of the assay within the lowest concentration of interest. In conclusion, in this method article, we describe a simple, sensitive, and cost-effective 2D-LC/MS/MS method suitable for the routine analysis of a complex of steroid hormones allowing high analytical specificity and sensitivity despite minimal sample processing and short throughput times.

Green and Efficient Determination of Fluoroquinolone Residues in Edible Green Fruits and Leafy Vegetables by Ultrasound-Assisted Extraction Followed by HPLC-MS/MS

In this work, a simple, quick and efficient analytical method for determination of human and veterinary fluoroquinolone antimicrobial residues in lettuce, cucumber and spinach is developed. The procedure entails a 6 min ultrasound-assisted extraction (UAE, 3 × 2 min) in an alkaline (2% v/v NH₃) aqueous solution containing Mg²⁺ ions (3 × 6 mL), with no need for organic solvents. The extract is submitted to cleanup on the HLB™ cartridge and the fluoroquinolones are separated and quantified by HPLC-MS/MS in a 10 min chromatographic run, using a small amount of acetonitrile in the mobile phase. The method, entirely developed in real matrices, is validated according to the updated analytical guidelines and provided suitable recoveries in the range of 67–116% and precision (RSD ≤ 20%, n = 3) at different concentrations (15, 70 and 150 ng g⁻¹), with method quantification limits of 2–10 ng g⁻¹. Fluoroquinolones were detected and quantified at concentrations from few to hundreds of nanograms per gram in vegetables from supermarkets, demonstrating the applicability of the method for monitoring residues of these pharmaceuticals.

Simultaneous Determination of Aflatoxins and Benzo(a)pyrene in Vegetable Oils Using Humic Acid-Bonded Silica SPE HPLC–PHRED–FLD

In the present work, a rapid, accurate, and cost-effective method was developed for the simultaneous quantification of aflatoxins and benzo(a)pyrene in lipid matrices, using solid-phase extraction (SPE) via humic acid-bonded silica (HAS) sorbents, followed by high-performance liquid chromatography coupled with photochemical post-column reactor fluorescence spectroscopy (HPLC–PHRED–FLD) analysis. The major parameters of extraction efficiency and HPLC–PHRED–FLD analysis were investigated and this method was fully validated. The limits of quantification and the limits of detection were 0.05–0.30 and 0.01–0.09 µg kg⁻¹, respectively. The recoveries were 66.9%–118.4% with intra-day and inter-day precision less than 7.2%. The results of 80 oil samples from supermarkets indicated a high occurrence of BaP, and most of concentrations were within the requirements of EU and China food safety regulations. This is the first utilization of HAS–SPE HPLC–PHRED–FLD to simultaneously analyze the occurrence of aflatoxins and benzo(a)pyrene in vegetable oils.

Magnetic Micro-Solid-Phase Extraction Using a Novel Carbon-Based Composite Coupled with HPLC-MS/MS for Steroid Multiclass Determination in Human Plasma

A micron-sized sorbent, Magn-Humic, has been prepared by humic acids pyrolysis onto silica-coated magnetite. The material was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), thermogravimetric analysis (TGA), and Brunauer, Emmett, and Teller (BET) surface area measurements and applied for simultaneous magnetic solid-phase extraction (MSPE) of glucocorticoids, estrogens, progestogens, and androgens at ng mL⁻¹ levels from human plasma followed by high-performance liquid chromatography coupled with mass spectrometry (HPLC–MS/MS). Due to the low affinity for proteins, steroids extraction was done with no need for proteins precipitation/centrifugation. As highlighted by a design of experiments, MSPE was performed on 250 µL plasma (after 1:4 dilution) by 50 mg Magn-Humic (reusable for eight extractions) achieving quantitative recovery and satisfying clean-up. This was improved by washing (2 mL 2% v/v formic acid) prior to analytes elution by 0.5 mL 1:1 v/v methanol-acetonitrile followed by 0.5 mL methanol; eluate reduction to 0.25 mL compensated the initial sample dilution. The accuracy was assessed in certified blank fetal bovine serum and in human plasma, gaining satisfactory recovery in the range 65–122%, detection limits in the range 0.02–0.3 ng mL⁻¹ (0.8 ng mL⁻¹ for 17-β-estradiol) and suitable inter-day precision (relative standard deviation (RSD) <14%, n = 3). The method was evaluated in terms of selectivity, sensitivity, matrix-effect, instrumental carry-over, and it was applied to human plasma samples.