Handbook Of Solid Phase Microextraction Pdf Download |LINK|

Abstract:Solid-phase microextraction (SPME) is a simple, sensitive, rapid and solvent-free technique for the extraction of analytes from gaseous, liquid and solid samples and takes a leading position among microextraction methods. Application of SPME in sample preparation has been increasing continuously over the last decade. It is most often used as an automatized fiber injection system coupled to chromatographic separation modules for the extraction of volatile and semivolatile organic compounds and also allows for the trace analysis of compounds in complex matrices. Since SPME was first introduced in the early 1990s, several modifications have been made to adapt the procedure to specific application requirements. More robust fiber assemblies and coatings with higher extraction efficiencies, selectivity and stability have been commercialized. Automation and on-line coupling to analytical instruments have been achieved in many applications and new derivatization strategies as well as improved calibration procedures have been developed to overcome existing limitations regarding quantitation. Furthermore, devices using tubes, needles or tips for extraction instead of a fiber have been designed. In the field of food analysis, SPME has been most often applied to fruit/vegetables, fats/oils, wine, meat products, dairy and beverages whereas environmental applications focus on the analysis of air, water, soil and sediment samples.Keywords: SPME; food analysis; environmental analysis; volatile compounds; aroma; off-flavor; GC; LC; SBSE

Use of solid phase microextraction (SPME) for cell culture metabolomic analysis allows for the attainment of more sophisticated data from in vitro cell cultures. Moreover, considering that SPME allows the implementation of multiple extractions from the same sample due to its non/low-depletive nature, time course studies using the same set of samples are thus facilitated via this method. Such an approach results in a reduction in the number of samples needed for analysis thus eliminates inter-batch variability related to biological variation occurring during cell culturing. The current work aims to demonstrate the capability of SPME for measurements of combretastatin A4 (CA4) effectiveness on non-small cell cancer cell line. A cultivation protocol was established in the 96-well plate, and a fiber format of SPME was selected for metabolite extraction. The extracellular metabolic pattern of cells was changed after administration of the tested drug. This suggests pharmacological activity of the administered compound towards the studied cell line model. Results support that the use of direct immersion SPME for analysis of cell cultures does not affect cells growth or contaminate sample. Consequently, SPME allows the attainment of accurate information regarding drug uptake, metabolism, and metabolomic changes in the studied cells induced by exposure to the drug simultaneously in a single experiment.

Left panel scheme of combretastatin A4 phosphate administration to A549 cell line, according to protocol 1. Right panel real view of sampling procedure in vial, according to protocol 2. (CA4-administration of combretastatin A4, SPME-solid phase microextraction, SRB- sulforhodamine B cytotoxicity assay).

Left panel scheme of combretastatin A4 phosphate administration to A549 cell line, according to protocol 2. Right panel real view of 96-well plate sampling procedure, according to protocol 2. (CA4P-administration of combretastatin A4 phosphate, SPME- solid phase microextraction, SRB- sulforhodamine B cytotoxicity assay).

Solid phase microextraction is presented in the current work as a suitable tool for high throughput tracking of metabolic changes in in vitro systems, either as part of one time-point investigations, or in time course studies, in which case SPME additionally offers the possibility of multiple analyses from the same samples due to its minimally-invasive nature, and negligible depletion capabilities. The different fiber lengths of the SPME devices used for the described protocols demonstrate the flexibility of the SPME method: the short coating enables direct sampling for time course analysis from low volumes in 96-well plates, while on the other hand, longer coatings can be employed in cases where multiple samplings are not needed, as is the case in time-course analyses, thus increasing the sensitivity of the method as well as the chances of finding metabolites present at very low concentrations. The current work corroborates that treatment of a non-small cell lung cancer cell line with combretastatin A4 and its prodrug, combretastatin A4 phosphate, results in alteration of cell metabolism. This is supported by the observed changed levels of endogenous compounds after administration of CA4 or CA4P. The In vitro cell-based platform is capable of metabolizing the prodrug of CA4, combretastatin A4 phosphate CA4P, to its active form. Moreover, the current work demonstrated that the intake of the drug by cells can be measured with SPME by means of temporal resolution. As employment of SPME does not disturb cell growth and only requires minimal sample consumption, SPME is thus shown to be compatible with routine cell culture protocols, as it enables the execution of other assays, such as SRB staining for cytotoxicity assessment, for instance, from the same sample, thus allowing for overall higher analysis precision as well as lower sample consumption.

Nanomaterials are extremely useful as sorbents for sample preparation, because of their varied morphologies, high surface area, surface-tovolumeratio, porosity, and ability to interact with samples in a variety of ways. Here, we review how nanomaterials are being used in a varietyof sample preparation techniques, such as dispersive solid-phase extraction (dSPE), solid-phase microextraction, stir-bar sorptive extraction, and matrix solid-phase dispersion.

Solid-phase microextraction (SPME) (14) is a solventless and miniaturized technique that enables analyte extraction and preconcentration in a single step (15). This equilibrium-based technique was introduced by Pawliszyn in the early 1990s, and has been applied successfully in many fields of analytical chemistry. SPME may be used to isolate analytes from the headspace (HS), or by direct immersion (DI) into the sample solution, depending on the Henry's law constant of the target compound (16). The latter, DI mode, is recommended for analysis of compounds in low levels in clean matrices, such as drug products (17), being a promising technique for E&L screening.

The solid-phase microextraction (SPME), invented by Pawliszyn in 1989, today has a renewed and growing use and interest in the scientific community with fourteen techniques currently available on the market. The miniaturization of traditional sample preparation devices fulfills the new request of an environmental friendly analytical chemistry. The recent upswing of these solid-phase microextraction technologies has brought new availability and range of robotic automation. The microextraction solutions propose today on the market can cover a wide variety of analytical fields and applications. This review reports on the state-of-the-art innovative solid-phase microextraction techniques, especially those used for chromatographic separation and mass-spectrometric detection, given the recent improvements in availability and range of automation techniques. The progressively implemented solid-phase microextraction techniques and related automated commercially available devices are classified and described to offer a valuable tool to summarize their potential combinations to face all the laboratories requirements in terms of analytical applications, robustness, sensitivity, and throughput.

In this study, the METs are classified according to their geometry and their characteristic of being exhaustive or nonexhaustive. Conversely, previous studies classified them generally into two categories according to Jochmann et al. [23] and Nerín et al. [24]: coated, as SPME fiber or in-needle/in ITME methods, and tubes or needles filled with sorbent material. The aim of this review is to show the fourteen commercially available solid-phase METs used for chromatographic separation and mass-spectrometric detection with their main features, highlighting the latest upswing in the availability and range of their automation.

Enhancements of high-throughput robotic microextraction systems have had an important impact on increasing the precision and throughput of analytical sessions and minimizing their time and cost. Moreover, the miniaturization of the extraction devices, coupled with the new portable, high-sensitive analyzers, and customized direct injection ports, could open new fields of applications, occupational, or forensic particularly. In 2019, Agilent Technologies (Santa Clara, US) introduced a new injection system, the QuickProbe, based on a vaporization inlet that is open to ambient air while having helium purged-flow protection to eliminate air leakage into the QuickProbe and MS ion source [35]. It is an innovative sample introduction technology that uses a thin glass tube as a sampling probe, touching directly liquid, solid, or powder samples before introducing it into the customized inlet for three to six seconds for vaporization. QuickProbe system could also provide rapid separation thanks to tailored QuickProbe column installed on Agilent analyzers [36].

The SPME technique was patented in 1989 [9], and Supelco (Bellefonte, US) introduced the first commercial SPME device in 1993 [38], which is improved in 2001 with a customized holder for sampling. Today, other companies propose SPME-like devices as Restek Corporation (Bellefonte, USA) or PAS Technologies (Magdala, Germany), which produces only polydimethylsiloxane (PDMS) fibers. The SPME is a fiber, contained in a stainless-steel needle coated with a liquid or solid sorbent phase. It was applied to sample various analytes from different matrixes, either gases or liquids [39]. Due to its geometry, one of its biggest drawbacks is fragility and lack of stability [40]. To face these features, Supelco has been studying on the development of SPME to obtain better physical stability for persistent reusability. Within this framework, GC-amenable StableFlex SPME fibers were proposed to improve the endurance of the fiber by coating, using the same extraction phases of traditional fused-silica core fibers, a more flexible fused-silica core. This extraction phase is in part connected to the core, leading to additional coating and fiber endurance, whilst maintaining the flexibility of the device. Lately, Supelco has released SPME fibers based on Nitinol-core (NiTi) SPME fiber, a metal alloy-based fiber made with a material characterized by high flexibility with better inertness compared to stainless steel [41]. This thinner metal alloy provides extra flexibility, whilst the needle is reinforced thanks to the thicker alloy in the plunger. Additionally, the tip is beveled to help the septa piercing of this thin needle; this kind of tip requires a septumless sealing systems to avoid septa coring. 2b1af7f3a8