Recent Advances in Analytical Techniques

The increasing need to characterize solid samples from different fields of science (e.g., advanced materials, geology, cultural heritage, biological tissue sections) is forcing the development of analytical techniques for accurate direct solid analysis in a wide variety of matrices. Laser ablation (LA) coupled to inductively coupled plasma – mass spectrometry (ICP-MS) allows the chemical characterization of solids both in bulk and in spatially–resolved analysis. LA-ICP-MS offers a precise and relatively fast measurement of heteroatoms at the trace and ultra–trace concentration level, including isotope ratios, with none or minimal sample preparation. Furthermore, recent research highlights the analysis of biological molecules by LA-ICP-MS. This book chapter reviews and discusses the principles, analytical performance, new instrumental developments and pros and cons of LA-ICP-MS. Selected representative applications are described related to bulk and spatially–resolved analysis.

Electronic noses and electronic tongues are bioinspired devices which mimic the ability of human noses and human tongues to identify different gases/vapours and liquids, respectively. Unlike their biologic homologous, electronic noses and tongues can also be used for quantitative purposes. They consist of an array of non-specific sensors with different selectivities towards analytes (cross-response) which provide a complex set of data that, by means of chemometric methods, allows the classification of samples, the quantification of selected analytes and the estimation of global sample properties. Among such devices, voltammetric electronic tongues deserve special attention, because they can generate a larger quantity of information. This means more power to discriminate similar samples and analytes with close responses, but also the need of more sophisticated chemometric methods for the analysis and interpretation of the data. In the last years, the popularisation of commercial screen-printed electrodes has encouraged the design of voltammetric electronic tongues based on such screenprinted devices modified with a large variety of chemical substances, biomolecules and nanomaterials. The versatility of voltammetric electronic tongues has stimulated the development of many applications, mainly in the fields of food analysis and environmental analysis, which are reviewed in this chapter.

Biopharmaceuticals main classes comprise recombinant proteins, antibodies, and nucleic-acid-derived products, while synthetic pharmaceuticals include a wide variety of organic compounds. The purification of (bio)pharmaceuticals, as part of downstream processing, is mainly carried out by chromatographic processes, which are responsible for the therapeutics high cost. Therefore, there is a crucial need on the development of novel and more efficient separation/purification processes or on the improvement of the current chromatographic-based ones, aiming at producing pharmaceuticals of high quality and at a lower cost. Amongst alternative techniques, it has been demonstrated that inorganic or organic (nano)particles, used in solid-phase extraction approaches, may be promising for the purification of (bio)pharmaceuticals. This chapter provides an overview on solid-liquid separation/purification processes used to obtain high purity and high quality pharmaceuticals. The main purification processes are described and summarized. The areas where there has been a sustainable progress, combined with improved therapeutic characteristics, are highlighted. Materials based on silica (nano)particles, carbon-based (nano)particles (carbon nanotubes, graphene and activated carbon) and magnetic (nano)particles are overviewed. Based on the reported results, nanotechnology may play a key role in future pharmaceutical developments and manufacturing, where the design of suitable functionalized (nano)particles is a crucial factor to enhance the selectivity and to obtain high purification and recovery yields of (bio)pharmaceuticals.

Among the numerous synthetic organic chemicals that are extensively produced, manufactured, and consequently used worldwide for many different purposes nowadays, such as polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), pharmaceutical drugs, and various other organic chemical species which are being considered as emerging pollutants, pesticides are included as well. The presence and occurrence of these xenobiotic substances not only in various environmental matrices (water, air, and soil), but also in biological tissues of different organisms, as well as in several compartments of raw or processed food of fruit, vegetal, and animal origin, has raised global scientific concerns regarding their potential toxicity towards non target organisms including humans. Furthermore, the efficiency of specific persistent organic contaminants to be magnified, and accumulated along the food chain has enacted strict legislations, regulations and guidelines regarding their use and maximum levels of their residues that are legally tolerated in or on food or feed.

Ensurace of food control and safety is achieved after the performace of extensive analytical stages of sample preparation which include extraction and/or clean-up techniques followed by instrumental analysis for the qualitative and quantitative determination of pesticide residues that are contained in complex matrices, such as food often in trace levels varying from ng kg-1 to μg kg-1. Therefore, the most important, fundamental, and crucial issue to overcome is the development of analytical methods characterized by high accuracy, sensitivity, selectivity, specificity and reliability that allow the simultaneous determination of more than one residue in a simple run (routine analysis). This chapter is aiming to review the most recent advances in developed and applied analytical techniques all over the world for the identification and quantification of pesticides in fruit and vegetable samples, focusing and emphasizing on the procedures of isolation, enrichment, elimination of matrix effects, separation and instrumental determination. Apart from parent compounds, the determination of primary metabolites and degradation products is being reviewed and discussed. Drawbacks and advantages occurring at each stage of the analytical procedure are critically reviewed, and research needs and future trends are also highlightened.

Honey is among the most consumed foods along the world with vast nutritional value. However, there is a lot of concern about the safety and the quality of honey products since there are a lot of incidents of honey adulteration. Furthermore, honey food industries, in response to food fraud, are seeking to detect the honey authenticity of honey products. The verification of honey authentication is very difficult. For this reason new analytical methods were developed including liquid and gas chromatography coupled to mass detectors. The melissopalynological characterization, the Hydroxymethylfurfural (HMF) content, the diastase activity, the polyphenol content, the sugars profile are among the most used parameters investigated for food adulteration and authenticity, In this chapter all different modern analytical methods used for the determination of all these parameters will be discussed. Finally, all different chemometric methods used in order to provide safe information about the authenticity and adulteration of honey will also be presented.

The last decades have seen an upsurge in the synthesis of coordination polymers (CPs), which became a notable topic of interest in the field of science due to their inherent features, such as porosity, larger inner surface area, tunable pore size, and diverse topologies and many more. The synthesis of CPs involves the use of petroleum-derived ligands, multi-step processes, use of volatile organic solvents and limited solubility. In addition, due to a continual rise in the cost and impending exhaustion of petroleum resources, the production of these CPs from renewable resources have been an area of keen interest among the researchers of both the industrial and academic world. Among all the renewable resources, cashew nut shell liquid (CNSL) and its constituents possessing inherent functional sites proved to be a valuable precursor for polymer as well as CPs synthesis. The CNSL/or its constituents (cardanol/Col) derived CPs with applications in wastewater treatment or as antibacterial agents are a great topic of interest.

In the present chapter, a brief description of petro-based as well as renewable resource (CNSL) based CP has been included and the analytical techniques that are used for the characterization of these CNSL based CPs in order to understand their composition, behavior and their potential applications in different fields have been discussed.