Chapter 2 Sampling and sample preparation

Antioxidant Capacity Determination in Plants and Plant‐Derived Products: A Review

“…So, ionic conduction and dipole rotation are the mechanisms underlying the conversion of electromagnetic energy to heat [54, 63]. The components of the sample absorb microwave energy in conformity with their dielectric constants [64]. When the plant material is found in a solvent transparent to microwaves, the elevated vapour pressure causes rupture of the cell wall of the substrate and frees the content into solvent [55].…”

Sample Preparation and Diagnostic Methods for a Variety of Settings: A Comprehensive Review

“…Nearly every analytical assay in use today requires some type of sample pretreatment or preparation in order to transform samples from their collected form into a form suitable for analysis [ 1 , 2 , 3 , 4 ]. While the target analytes and underlying theories of analytical procedures vary greatly, most assays consist of sample collection, isolation of target analytes, detection of the targets, quantification, and the interpretation and handling of the resulting data [ 1 , 2 , 4 , 5 , 6 , 7 ]. In most cases, sample preparation is taken to mean any operations performed on a sample prior to instrumental analysis, typically consisting of the separation of target analytes from some matrices, the concentration of analytes, and the chemical or physical modifications made to improve downstream separation or detection [ 1 , 2 , 4 ].…”

“…It is worth noting that while there is no official agreement on the terms, sample preparation is generally associated with the chemical modifications to a sample while sample pretreatment is usually associated with physical modifications [ 1 , 2 , 4 ]. The typical examples of sample preparation include processes such as dissolving samples in a solvent, extracting analytes from a matrix, separating interfering components of a sample from the target analytes, enriching target analytes to make their detected signal stronger, and reacting analytes with some reagent to convert them into measurable derivatives, while the typical examples of sample pretreatment include changes in physical state such as freezing or crystallizing, grinding of a sample, or polishing or sputtering of the surface of a sample [ 1 , 2 , 5 , 6 ]. Due to the ever-growing number and constant improvement of sample preparation techniques and the technology supplementing them, such as automation and nanomaterials, many reviews and book chapters have been written both describing and classifying techniques for extractions, separations, derivatizations, enrichments, and labeling [ 1 , 2 , 3 , 4 , 6 , 7 , 8 , 9 , 10 , 11 , 12 ].…”

“…Due to the ever-growing number and constant improvement of sample preparation techniques and the technology supplementing them, such as automation and nanomaterials, many reviews and book chapters have been written both describing and classifying techniques for extractions, separations, derivatizations, enrichments, and labeling [ 1 , 2 , 3 , 4 , 6 , 7 , 8 , 9 , 10 , 11 , 12 ]. Since many analytical methods and workflow processes are multilayered or sequential, adequately developed sample preparation is not only essential for obtaining a clean sample for analysis but also for ensuring that the subsequent steps and instrumentation used in an analytical process are not negatively impacted [ 1 , 2 , 3 , 4 , 5 , 6 ]. Because of this, the sample preparation/pretreatment steps of a given method greatly impact the costs, time, and overall success of an analytical process [ 1 , 2 , 3 , 4 , 5 , 6 , 13 ].…”

“…Since many analytical methods and workflow processes are multilayered or sequential, adequately developed sample preparation is not only essential for obtaining a clean sample for analysis but also for ensuring that the subsequent steps and instrumentation used in an analytical process are not negatively impacted [ 1 , 2 , 3 , 4 , 5 , 6 ]. Because of this, the sample preparation/pretreatment steps of a given method greatly impact the costs, time, and overall success of an analytical process [ 1 , 2 , 3 , 4 , 5 , 6 , 13 ]. More specifically, sample preparation is estimated to account for approximately 66–80% of sample analysis time, introduce much of the error in interlaboratory analyses, hinder the identification of sources of error arising from multiple difficulties, introduce environmental hazards due to the large volume of hazardous solvents and waste generated, and present health hazards to technicians or operators involved in a process due to exposure to large volumes of harmful solvents and residues involved in processes such as extraction [ 3 , 4 , 10 ].…”