Advances in Sample Preparation最新文献

The principle of Fourier Transform Infrared (FTIR) spectroscopy is based on atoms vibration and rotation, and it has become a universal and widely used spectral methodology to detect the internal molecular structures in all kinds of fields. Numerous review articles related to the applications of FTIR spectroscopy have been published in recent years. In addition, more and more scientists are aware the significance role of sample preparation to improve our life quality in life science. However, the application of FTIR spectroscopy in sample preparation hasn't been summarized. Thus, in the current paper, the application of FTIR spectroscopy in sample preparation was reviewed with the focuses on characterization of separation materials including both solid sorbents and liquid extractants, and the extraction mechanisms involved in the separation towards different targets including inorganic molecules such as rare earth elements, organic molecules such as phenolics, pharmaceuticals and illicit-drugs, and biomacromolecules of DNA and proteins. We believe that the current paper will be interested for the researchers in food science, forensic medicine, clinical medicine, environmental analysis and analytical chemistry.

The constant pursuit of efficient and cost-effective methods for analyzing human samples drives ongoing innovation in biomedical research. Introduced in 2014, Volumetric Absorptive Microsampling (VAMS) technology ensures fixed blood volume absorption and enhanced sample uniformity. Our study aims to enhance VAMS functionality by integrating sample preparation onto the device primarily used for sample collection. This involves the adsorption of antibodies onto VAMS tips, enabling instant sample clean-up at the time of sample collection. Using human chorionic gonadotropin (hCG) as a model analyte, we evaluated the qualitative and quantitative performance of Affinity-VAMS. First, we showed that adsorbing and covalently binding monoclonal antibodies to VAMS tips results in capturing of the target analyte in comparison to unmodified VAMS. Due to the ease of preparation, we moved forward using antibody adsorption to VAMS tip and optimized the procedure. Optimization of the procedure involved fine-tuning the antibody coupling step, washing process, and determining the optimal amount of antibody required, leading to a streamlined process with significant time savings up to two days. Recovery experiments demonstrate successful capture of the target analyte by the Affinity-VAMS, while matrix effects and stability assessments indicate no negative effects from serum matrix or storage conditions. Finally, quantitative analysis shows promising performance of the Affinity-VAMS in detecting different concentrations of the target analyte in the concentration range between 7.5 - 25 ng·mL⁻¹. The calculated correlation factor was R² of 0.9988 and limit of detection 2.5 ng·mL⁻¹. The precision lays within the ICH guidelines for bioanalytical method validation. While this report is focused on the proof of concept of the Affinity-VAMS, our findings demonstrate the potential for the usage of modified VAMS in remote sampling and integrated sample processing, enhancing biomarker analysis in clinical and research settings.

In this work, a novel magnetic nanoparticle (Fe₃O₄@SiO₂@MIL-53(Al)-NH₂) constructed on the basis of metal-organic frameworks (MOFs, MIL-53(Al)-NH₂) was prepared, which was characterized by Fourier transform infrared spectroscopy (FT-IR), transmission electron microscope (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Good preparation reproducibility was obtained with the relative standard deviations (RSDs) ranging from 6.6 to 13.1 % (n = 6). In addition, the prepared Fe₃O₄@SiO₂@MIL-53(Al)-NH₂ possesses many merits, including simple preparation, greenness, good water/solvent stability and high specific surface area. The Fe₃O₄@SiO₂@MIL-53(Al)-NH₂ was used as an adsorbent for magnetic solid phase extraction (MSPE) of estrogens in fish samples. To achieve higher extraction efficiency, several factors including extraction time, pH value, ionic strength and desorption time were explored. Compared with other methods, the developed method exhibits high extraction efficiency, fast extraction kinetics and suitable for simultaneous analysis of large number of samples. The method was successfully applied to the analysis of estrogens in (spiked) fish samples, and good recoveries were obtained.

Pipette tip-electrospray is a useful technique that synergically combines sample preparation and ambient ionization mass spectrometry for the rapid analysis of samples. In this work, the development of pipette tip extraction (PTE) is evaluated under two workflows that can be adapted to different analytical scenarios. Micro-handling PTE (MH-PTE) is an inherently portable technique that can be on-site applied. Centrifugal PTE (C-PTE), firstly presented here, allows a high sample throughput just requiring a benchtop centrifuge. The combination of both MH-PTE and C-PTE with pipette tip-electrospray is evaluated in this work for determining codeine and morphine, two metabolically related drugs, in urine and applied to the analysis of real samples. In the case of MH-PTE, intended to be on-site applied, the chemical stability of the analytes once extracted in the tips plays a crucial role. This stability has been studied in detail, simulating several transport/storage conditions compatible with regular postal services. The analytical features of both combinations are similar, although C-PTE provides a better sensitivity in terms of limit of detection (0.3 µg L⁻¹ for codeine and 0.6 µg L⁻¹ for morphine) compared to MH-PTE (0.6 µg L⁻¹ for codeine and 1.5 µg L⁻¹ for morphine). Moreover, the sample throughput provided by C-PTE is higher (up to 72 samples h⁻¹) than that provided by MH-PTE (up to 12 samples h⁻¹).

Despite being a minimally invasive sample source, dried blood spots (DBS) generally pose the challenge of efficient sample extraction for broad metabolomics applications. This is particularly true for the quantification of steroids using non-derivatized liquid chromatography tandem mass spectrometry assays. To address these limitations, we have demonstrated the use of electric field as a driver for sample preparation from DBS samples to simultaneously quantify testosterone (T), 17α-hydroxyprogesterone (17-OHP), progesterone (P), and cortisol (C), using both standard electroporation cuvettes, as well as a novel custom vertical electric field setup. Our findings, backed by computational modeling, show that a 10V DC application for 180 s can draw out twice the amount of the aforementioned steroids from both Whatman-903 and DMPK-C sample collection cards using our novel device when compared to standard solvent-based collection methods. This study not only introduces the use of electric field for sample preparation for metabolomics, but additionally introduces a novel device that eliminates the electric double layer effect in the process.

Analysing biomarkers in human serum could be used as an effective and less invasive approach for the diagnosis of lung cancer; however, biomarker detection reliability is highly limited due to matrix effects. Herein, aqueous biphasic systems (ABS) are studied as platforms for human serum pretreatment, allowing the simultaneous depletion of high abundant proteins and biomarker extraction. By using ABS varying the polyethylene glycol (PEG) molecular weight between 400 and 6000 g·mol⁻¹ and adopting phosphate buffer as the other phase-forming component, the depletion of the high abundance serum proteins immunoglobulin G (IgG) and human serum albumin (HSA) is induced at the ABS interphase, through precipitation, forming a three-phase partitioning system (ABS-TPP). Maximum depletion efficiencies of 99 % for IgG and 70 % for HSA were achieved in one step using PEG 1500-based ABS-TPP. On the other hand, lung cancer biomarkers, such as CYFRA 21–1, are extracted to the PEG-rich phase of the same ABS-TPP with recovery yields of 91 %. This work shows that a proper selection of the PEG molecular weight in the ABS composition leads to the efficient depletion of high-abundance proteins and extraction of cancer biomarkers from human serum, in a single step, confirming the potential of ABS for sample pretreatment to improve biomarker analysis.

This paper represents an improved method for on-site quantitation of benzene, toluene, ethylbenzene, and xylenes (BTEX) in atmospheric air using solid-phase microextraction (SPME) and portable gas chromatography with a split/splitless inlet and photoionization detector (GC-PID). The developed method includes air pumping to four replicate 250 mL gas sampling bulbs, three of which are extracted by 85 µm Carboxen/polydimethylsiloxane (Car/PDMS) coating at 40°C, while the last one is spiked with BTEX standard in nitrogen and extracted under the same conditions. Compared to other similar SPME-based methods, the developed method does not require a standard gas generator and traceable certified permeation tubes for instrument calibration.

The method was applied for on-site BTEX quantitation in air of Talgar, Almaty oblast, Kazakhstan in February and March 2024, at two different extraction times, among which 15 min was chosen as optimal because it provided sufficient detection limits of ethylbenzene, and xylenes. The on-site standard addition calibration allowed accurate BTEX quantitation. In February, only benzene (18.3 and 6.8 µg/m³) and toluene (15.7 and 8.5 µg/m³) were detected. In March samples, concentrations of benzene were 12.3 and 7.4 µg/m³, toluene - 23 and 5.4 µg/m³, ethylbenzene – 5.5 µg/m³ and not detected, m-/p-xylene - 3.6 and 2.1 µg/m³, o-xylene - 6.8 and 10.6 µg/m³. The LODs for benzene, toluene, ethylbenzene, m-/p-xylene, and o-xylene were 0.07, 0.3, 2, 0.8 and 2 µg/m³, respectively. The developed method can be recommended for quick and low-cost on-site quantification of BTEX in atmospheric air, particularly at remote locations.

The primary objective of this contribution is to offer insights into fundamentals associated with typical sample preparation, facilitating rational design of new analytical technologies and effective optimization of existing techniques. Sample preparation stands a pivotal stage in the analytical process. Unfortunately, the optimization of associated parameters often relies on trial and error rather than systematic scientific methodologies. If an extraction method provides good recovery of spikes of standards, it is assumed that it works well and no further consideration is given to the underlying principles driving its performance. In the realm of sample preparation, the fundamentals of method optimization are not accorded the same significance as in other technologies, such as chromatography or mass spectrometry. Consequently, the fundamentals of sample preparation are typically overlooked in analytical chemistry curricula.

A notable impediment to progress in the sample preparation area is underdeveloped understanding of the fundamentals of extraction, particularly when dealing with natural, often complex samples, where native analyte-matrix interaction is different compared to spikes. This stands in contrast to the physiochemically simpler systems employed in separation and quantification steps, such as chromatography and mass spectrometry.

A careful consideration of the underlying principles of sampling and sample preparation can lead to the creation of more efficient and environmentally friendly technologies. Embracing these principles aligns with global shift towards more sustainable future, challenging the perception that sample preparation is solely an artistic endeavour and highlighting its potential as a scientifically grounded discipline.

As the global demand for sustainable and renewable resources intensifies, there is an imperative to explore innovative technologies for biomass valorization. This review delves into a promising avenue, providing an overview of green approaches that combine solid-liquid extraction (SLE) with a type of solvent known as deep eutectic solvents (DESs) in a synergistic manner. SLE, a conventional method for isolating bioactive compounds from biomass, is recognized for its effectiveness in sample preparation. However, it often involves the use of environmentally harmful solvents. Subsequently, DESs have emerged as an eco-friendly alternative to traditional solvents. Composed of naturally occurring and benign components, these DESs exhibit unique properties that render them suitable for various extraction processes. The integration of SLE with DESs introduces a novel approach to biomass valorization. This review explores the synergistic effects between SLE and DESs to optimize extraction yields, improve selectivity, and reduce overall energy consumption. Furthermore, the nature of DESs aligns with the principles of green chemistry, positioning them as a sustainable alternative to traditional solvents.

Due to the increasing world population and consumer desire for sustainable and nutritious protein sources, the food industry is currently experiencing tremendous pressure to develop innovative, sensorially acceptable, health-promoting plant-based products. Plant proteins, specifically pulse proteins arise as a healthy and sustainable protein source for food applications. However, the use of pulse protein is challenged by its intrinsic undesirable aroma often described as beany, grassy, and green. These off notes can be inherent, i.e. generated from plant metabolism, or produced during processing and/or storage and encompass a broad variety of chemical classes. Since aroma plays a major role in consumer acceptance and eating habits and due to its chemical complexity, proper analytical methods must be used for its assessment. Considering that the effectiveness of an analytical method is significantly influenced by its sample preparation step, this review focuses on sample preparation techniques for monitoring the volatile profile of pulse proteins, their advantages, and disadvantages, while concurrently highlighting the potential of novel technologies for advancing this critical application.