Modern Sample Preparation for Chromatography

Modern Sample Preparation for Chromatography, Second Edition explains the principles of sample preparation for chromatographic analysis. A variety of procedures are applied to make real-world samples amenable for chromatographic analysis and to improve results. This book's authors discuss each procedure’s advantages, disadvantages and their applicability to different types of samples, along with their fit for different types of chromatographic analysis. The book contains numerous literature references and examples of sample preparation for different matrices and new sections on green approaches in sample preparation, progress in automation of sample preparation, non-conventional solvents for LLE (ionic liquids, deep eutectic mixtures, and others), and more.

Part 1 - General concepts in sample preparation

CHAPTER 1. Preliminaries to sample preparation

1.1 Collection of information and planning for a chromatographic analysis

General comments

Flow of typical sampling and sample preparation process

Chromatographic core analysis

Collection of information regarding the analysis

Planning the analysis

Chemicals and certified reference materials

References 1.4

1.2 Statistical evaluation of quantitative data

General aspects

Precision and accuracy in quantitative chemical analysis

Sensitivity and limit of detection

Least square regression and linearity of the instrumental response

Propagation of uncertainty

Comparison of two procedures regarding accuracy

Comparison of two procedures regarding precision

Evaluation of the experimental design in sample preparation

References 1.2

1.3 Validation of an analytical method

General aspects

Validation procedures

Parameters for method validation

Acceptance criteria for validation

References 1.3

1.4 Sampling
General comments

Sampling procedures

Some theoretical aspects of sampling

Brief comments on sampling of gases

Brief comments on sampling of liquids

Brief comments on sampling of solids

Brief comments on sampling of mixed-phases materials

Some comments on sampling of biological materials

Comments on handling, preservation, and storage of samples

References 1.4

CHAPTER 2. The role of sample preparation

2.1 Preliminary processing of the sample

General comments

Sample homogenization

Adjustment of water content in samples (drying)

Sample dissolution

Resampling for further reduction of sample size

Green approaches in sample preparation

References 2.2

2.2 Routine manipulations of the sample

General comments

Weighing

Volume measuring

Mixing and dilution

Heating and cooling

Other routine sample manipulation

Preservation of sample integrity during processing

References 2.1

2.3 Sample cleanup and fractionation

General comments

Cleanup and fractionation procedures

Analyte recovery during sample cleanup

References 2.3.

2.4 Concentration of the sample

General comments

Enrichment factor

References 2.4

2.5 Chemical modifications of the sample

General comments

Chemical changes for sample dissolution

Chemical changes for cleanup and fractionation purposes

Chemical modification for the enhancement of detection

Chemical modification for enhancing the separation in core chromatography

References 2.5

2.6 Selection of a sample preparation procedure

General comments

Development of a sample preparation scheme based on preliminary information

"Dilute and shoot" in chromatographic analysis

References 2.6

2.7 Automation and high throughput in sample preparation

General comments

Off-line automation and sample preparation

On-line automation and sample preparation

Software controlling automation in sample preparation

High-throughput sample preparation

References 2.7

CHAPTER 3. Chromatography as a core step for an analytical procedure

3.1 Basic concepts in chromatography

General comments

Common types of chromatography

Basic characterization of a chromatographic process

Qualitative chromatographic analysis

Quantitative chromatographic analysis

Selection of the internal standards in chromatographic analysis

The matrix effects in chromatography

Effect of medium (solvent) used for sample injection

References 3.1

3.2 Overview of gas chromatography

Retention and separation mechanism in gas chromatography

Typical GC instrumentation

Injection and injection port of a GC

The oven of a gas chromatograph

Chromatographic columns

Detectors in gas chromatography

The need for sample preparation in GC

References 3.2

3.3 Overview of high performance liquid chromatography

Retention and separation mechanism in liquid chromatography

Typical HPLC instrumentation

Solvent supply and pumping system

Mobile phase in HPLC

Injectors

Chromatographic column

Detectors in HPLC

The need for sample preparation in HPLC

References 3.3

3.4 Other chromatography types used as core analytical method

General comments

References 3.4.

Part 2 - Main sample preparation techniques

CHAPTER 4. Mechanical processing in sample preparation

4.1 Grinding and sieving

General comments

Particle size reduction

Sieving

References 4.1

4.2 Filtration, microfiltration, and ultrafiltration

General aspects

Theory of filtration of solids from liquids

Filters and membranes properties

Filters and membranes materials

Filtering devices in the laboratory

Continuous filtration

In-vivo application of ultrafiltration

References 4.2

4.3 Centrifugation

General aspects

The use of centrifugation in connection with filtration and ultrafiltration

References 4.3

CHAPTER 5. Phase transfer in sample preparation

5.1 Distillation, vaporization, and drying

General comments

Boiling point of liquids

Theory of gas-liquid equilibrium for two-component systems

Dependence of boiling point on pressure

Distillation

Distillation under vacuum plus centrifugal force

Steam distillation and other distillation processes

Vaporization

Drying and freeze-drying

Cryofocusing

References 5.1

5.2 Physical dissolution, crystallization, and precipitation

General comments

Dissolution process (physical dissolution) in sample preparation

Solvents used in sample preparations

Hildebrand solubility parameter

Solubility based on octanol/water partition coefficient

Rate of dissolution

Solubility of ionic compounds

Selection of sample solvent for injecting in a chromatographic instrument

Crystallization and precipitation

References 5.2

CHAPTER 6. Solvent extraction

6.1 Properties of solvents relevant in the extraction process

General comments

Solvent density, viscosity, and diffusion coefficient

Superficial tension

Dielectric constant, dipole moment, and polarizability

Hydrogen bonding of solvent molecules

Miscibility of solvents

Solvent characterization based on octanol/water partition coefficient

Solvent characterization based on liquid-gas partition

Solvent characterization based on solvatochromic model and Kamlet-Taft parameters

Solvent characterization based on other parameters

References 6.1

6.2 Conventional liquid-liquid extraction

General comments

Liquid-liquid partition equilibrium

Distribution coefficient

Partition equilibrium for ionic species, metal complexes, and ion pairs

Elementary thermodynamic theory for solvent extraction

Common liquid-liquid extraction procedures

Quantitation when LLE is part of sample preparation

Selection of solvents for the extraction process

The influence of pH on extraction

Chemical modifications that affect extraction

Non-chemical factors affecting extraction Separation using liquid-liquid extraction

References 6.2

6.3 Special liquid-liquid extraction procedures

General comments

Single drop-phase microextraction (SDME)

Membrane-assisted solvent extraction (MASE)

Microporous membrane liquid-liquid extraction (MMLLE)

Hollow fiber liquid phase microextraction (HF-LPME)

Mass transfer in LPME

Liquid-liquid-liquid-microextraction (LLLME)

Dispersive liquid-liquid microextraction (DLLME)

Salting-out assisted LLE (SALLE)

Liquid-liquid extraction with low temperature partitioning

Cloud-point extraction (CPE)

Electrochemically-modulated LLE

Simultaneous distillation and extraction

Other LLE variants

Automation in LLE

References 6.3

6.4 Conventional liquid-solid extraction

General comments

The rate of extraction in LSE

Solvents used in SLE

Simple extraction conditions

Soxhlet extraction

Separation using liquid-solid extraction

References 6.4

6.5 Accelerated solvent extraction

General comments

Instrumentation in ASE

Selection of parameters for ASE operations Pressurized hot water extraction (PHWE)

References 6.5

6.6 Microwave assisted solvent extraction (MASE) and ultrasound assisted extraction (UAE)

General comments

Theory of microwave usage

Practice of microwave extraction

Development of other related MASE techniques

Ultrasound assisted extraction

References 6.6

6.7 Supercritical solvent extraction

General aspects

Elementary theory of SFE extraction

Diffusion coefficients for supercritical fluids

Efficiency and selectivity in SFE

Steps in the SFE process

Optimization of the extraction

Expansion of fluid and collection process in SFE

SFE on-line with other chromatographic techniques

References 6.7

6.8 Solvent-gas extraction

General aspects

Headspace single-drop microextraction (HS-SDME)

References 6.8

CHAPTER 7. Solid-phase extraction

7.1 Conventional solid-phase extraction

General comments

Practice of conventional solid-phase extraction

Quantitation with a chromatographic method when SPE is part of sample preparation

Equilibrium in solid-phase extraction

Comparison of SPE with liquid chromatography

Breakthrough volume in SPE

References 7.1

7.2 Chemical nature of materials used as SPE sorbent and their characterization

General comments

Inorganic porous materials

Inorganic porous materials with an organic bonded surface

Organic synthetic polymers

Organic natural polymers

Metal organic frameworks (MOFs) and covalent organic frameworks

Magnetic nanoparticle sorbents

Other materials used as SPE sorbents

Composites

Physical properties of materials used as SPE sorbent

Parameters characterizing SPE performance

References 7.2

7.3 Types of SPE sorbents according to their functionalities or function

General comments

Non-polar and weak polar SPE sorbents

Polar SPE sorbents

Ion exchange SPE sorbents

Chelating ion exchange resins

Affinity, immunoaffinity and aptamer sorbents

Molecular imprinted polymers

Restricted access media

Mixed-mode sorbents

Moisture and particulate removal SPE

Adsorbents

Other types of conventional sorbents used for SPE

Monolithic materials

Electrospun nanofibers

Fabrics

Novelty sorbents

References 7.3

7.4 Formats used in SPE

General comments

Design and characteristics

References 7.4

7.5 Retention and elution mechanisms in SPE

General comments

Retention and elution on hydrophobic phases

Retention and elution on polar phases

Retention and elution on ion exchange phases

References 7.5

7.6 Solvents used in solid-phase extraction

General comments

Sorbent conditioning

Selection of solvent for solute retention

Selection of solvent for solute elution

References 7.6

7.7 Selection and optimization of solid-phase extraction

Making the sample amenable for SPE

Optimization of sorbents and solvents selection

References 7.7

7.8 Solid-phase extraction from headspace

General aspects

Sorbents used in headspace analysis

Basic theory of static headspace extraction

Practice of static headspace analysis

Basic theory of dynamic headspace extraction

Practice of dynamic headspace analysis

Desorption of the analytes from the trap

Purge and trap procedures

Quantitation in headspace techniques

Open tubular trapping

References 7.8

7.9 Solid-phase microextraction (SPME)

General comments

Basic theory of the retention of analytes on SPME fiber

Common coatings for SPME fibers

Other SPME coatings

Desorption of analytes and conditioning of the SPME fiber

Optimization of SPME analysis

Qualitative and quantitative analysis with SPME

Novel alternatives to the use of SPME

On fiber derivatization in SPME

SPME automation

References 7.9

7.10 Stir-bar sorptive extraction (SBSE)

General comments

Practice of SBSE

Sorptive phase in SBSE

Theory of SBSE

References 7.10

7.11 Matrix solid-phase dispersion (MSPD)

Basic principle of MSPD

Certain details on MSPD technique

References 7.11

7.12 QuEChERS technique

General comments

Steps of a QuEChERS procedure

References 7.12

CHAPTER 8. Chromatographic procedures as preliminary separations

8.1 Thin layer and open column liquid chromatography as sample preparation

General comments

Thin layer chromatography as sample preparation

Open (large) column liquid chromatography as sample preparation

References 8.1

8.2 Size exclusion chromatography (HPLC-SEC) used in sample preparation

General comments about size exclusion

Short theoretical background of SEC separation

Stationary phases used in SEC

Use of SEC as a sample preparation procedure

References 8.2

8.3 Other chromatographic techniques used for sample preparation

General comments

Flash chromatography

Counter current chromatography

References 8.3

CHAPTER 9. Membrane separations as sample preparation techniques

9.1 Gas diffusion through membranes

General comments

Basic theory of gas diffusion

Utilization of gas diffusion through membranes as sample preparation

References 9.1

9.2 Membranes used in special liquid-liquid extraction

General comments

References 9.2

9.3 Reversed osmosis and dialysis

General comments

Reverse osmosis

Dialysis

Ion exchange membranes

References 9.3

CHAPTER 10. Electroseparations in sample preparation

10.1 Electrophoretic techniques

General comments

Theoretical aspects of electrophoretic separations

Electrophoretic techniques

References 10.1

10.2 Other electroseparation techniques

General comments

Electro-membrane LLE

References 10.1

CHAPTER 11. Other separation techniques in sample preparation

11.1 Overview of ion exchange use in sample preparation

General comments

Applications of ion exchangers in sample preparation

References 11.1

11.2 Other techniques in sample preparation

General comments

Examples of applications as sample preparation for chromatography

References 11.2

CHAPTER 12. The role of derivatization in chromatography

12.1 Derivatization for sample dissolution

General comments

Sample dissolution by pH change

Other common dissolution procedures using chemical reactions

References 12.1

12.2 Improvement of gas chromatographic analysis by derivatization

General comments

Procedures for performing derivatization for gas chromatography

Derivatization for making polar and/or nonvolatile compounds amenable for GC

The role of derivatization in the improvement of separation

Derivatization for improving sensitivity of detection

Derivatization for improving compound identification

Improvement of quantitation accuracy through derivatization

References 12.2

12.3 Improvement of liquid chromatographic analysis by derivatization

General comments

Procedures for performing derivatization for liquid chromatography

The role of derivatization in the improvement of separation

The role of derivatization in the improvement of detection sensitivity

Improvement of quantitation accuracy through derivatization

Derivatization for the improvement of stability of the analyte

References 12.3

12.4 Derivatization for chiral separations

General comments

Chromatographic chiral separations

Derivatization with non-chiral (achiral) reagents

Diastereoisomers generated by derivatization with chiral reagents

References 12.4

CHAPTER 13. Chemical reactions used in analytical derivatizations

13.1 Reactions with formation of alkyl or aryl derivatives

General comments

Alkylation and arylation mechanisms Common alkylation reagents

Artifact formation in alkylation reactions

References 13.1

13.2 Reactions with formation of silyl derivatives

General comments

Some aspects of silylation mechanism

Reagents used for silylation

Silylation for the introduction of groups other than TMS

Artifact formation in trimethylsilyl derivatizations

References 13.2

13.3 Derivatives formation through acylation reactions

General comments

Some aspects regarding acylation mechanism

Typical acylation reagents

Derivatization with chloroformates

Derivatization with sulfonyl derivatives

Derivatization with isocyanates, isothiocyanates, carbonyl azides

Artifact formation in acylation reactions

References 13.3

13.4 Reactions of addition to carbon-heteroatom multiple bonds involved in derivatization

General comments

Some aspects regarding the reaction mechanism for addition to a hetero multiple bond

Reactions at the carbonyl group in aldehydes and ketones

Reactions at N=C group in isocyanates and isothiocyanates

Other reactions involving addition to a hetero multiple bond

References 13.4

13.5 Derivatization reactions with formation of cyclic compounds

General comments

Formation of nonaromatic cycles containing oxygen atoms

Formation of aromatic cycles containing one nitrogen atom

Reactions with the formation of azoles and related compounds

Reactions with formation of azines and related compounds

Reactions with formation of cyclic siliconides, cyclic phosphonothioates, and cyclic boronates

References 13.5

13.6 Other derivatization reactions

General comments

Reaction of addition to a double bond

Oxidations and reductions

Hydrolysis

Substitution reactions at the aromatic ring

Complexation and formation of coordinative compounds with metal ions

Other reactions

References 13.6

13.7 Derivatization reactions on solid support or involving solid phase reagents

Derivatization on a solid phase

Solid phase reagents

References 13.7

CHAPTER 14. Chemical degradation of polymers
for chromatographic analysis

14.1 Chemical degradation of polymeric carbohydrates

General comments

Polysaccharide structure

Steps in polysaccharide analysis

Identification of the constituent monosaccharides, their D or L configuration, and polymerization degree

Determination of the position of glycosidic linkages

Determination of the sequence of monosaccharide residues

References 14.1

14.2 Chemical degradation of proteins for chromatographic analysis

General comments

References 14.2

14.3 Chemical degradation of other macromolecular compounds for chromatographic analysis

General comments Degradation of nucleic acids

Degradation of lignin

References 14.3

CHAPTER 15. Comments on sample preparation in chromatography for different types of materials

15.1 Sample preparation techniques for the environmental analysis

(air, water and soil)

General aspects Analysis of gaseous samples

Basic operations in sample preparation for water analysis

Extraction of volatile and non-volatile compounds from soil samples

Sample preparation for the analysis of various environmental pollutants

References 15.1

15.2 Sample preparation for the analysis of pharmaceuticals

General aspects

Quality control of pharmaceuticals

Clinical trials

References 15.2

15.3 Sample preparation for the analysis of biological samples

General aspects

Handling, preservation and storage of biological samples

Analysis of breath condensate and volatiles emitted from skin or bodily fluids

Analysis of liquid samples of biological origin

Analysis of solid samples of biological origins

References 15.3

15.4 Sample preparation for food and agricultural products

General aspects

Food and beverage analysis

Agricultural products

References 15.4

15.5 Sample preparation related to the analysis of other materials and/or processes

General comments

Archeological artifacts

Cosmetics

Detergents

Dyes and pigments

Preservatives

Tobacco and cigarette smoke

References 15.5

Life Sciences

Physical Sciences & Engineering

Social Sciences & Humanities

Health

Modern Sample Preparation for Chromatography

Purchase options

Save 50% on book bundles

Institutional subscription on ScienceDirect

Serban C. Moldoveanu

Victor David