This review covers recent applications of near infrared (NIR) spectroscopy in the determination of physico-chemical and morphological parameters of polymeric materials. Near infrared measurements in the diffuse reflection mode are highlighted, which analyse the structural parameters such as porosity, surface area and particle size. Fundamentals and applications of the technique are discussed and examples of quantitative and qualitative analysis are explained. Various approaches like on-and in-line techniques, bulk measurements and kinetic studies for recording spectra are discussed. Furthermore, this review addresses the development of calibrations, which allow for the differentiation and quantification of materials with varying physical and morphological properties. Parameters like constitution, composition and crystallinity have a strong affect on the material characteristics. Therefore, chemical, physical and mechanical properties of synthetic as well as natural substances, such as polymeric composites and cotton or wool, need to be studied in-depth. To sum up, NIR spectroscopy has been developed as a flexible, robust and high-throughput analytical method that can be combined with chemometric and multivariate data analysis for fast and reliable screening in material science.

The use of non-invasive methods for detecting biomarkers opens a new era in patient care, since clinical investigators have long been searching for accurate and reproducible measurements of putative biomarkers. There are many factors which make this research challenging, beginning with lack of standardization of sample collection and continuing through the entire analytical procedure. Among the variety of methods so far used for biomarker screening, capillary electrophoresis represents a robust, reliable, and widely used analytical tool. This review will focus on recent applications of CE to the analysis of body fluids and tissues for identification of biomarkers.

A method based on near-infrared spectroscopy (NIRS) was developed for the rapid and non-destructive determination and quantification of solid and dissolved amino acids. The statistical results obtained after optimisation of measurement conditions were evaluated on the basis of statistical parameters, Q-value (quality of calibrations), R(2), standard error of estimation (SEE), standard error of prediction (SEP), BIAS applying cluster and different multivariate analytical procedures. Experimental optimisation comprised the selection of the highest suitable optical thin-layer (0.5, 1.0, 1.5, 2.0, 2.5, 3.0 mm), sample temperature (10-30 degrees C), measurement option (light fibre, 0.5 mm optical thin-layer; boiling point tube; different types of cuvettes) and sample concentration in the range between 100 and 500 ppm. Applying the optimised conditions and a 115-QS Suprasil cuvette (V = 400 microl), the established qualitative model enabled to distinguish between different dissolved amino acids with a Q-value of 0.9555. Solid amino acids were investigated in the transflectance mode, allowing to differentiate them with a Q-value of 0.9155. For the qualitative and quantitative analysis of amino acids in complex matrices NIRS was established as a detection system directly onto the plate after prior separation on cellulose based thin-layer chromatography (TLC) sheets employing n-butanol, acetic acid and distilled water at a ratio of 8:4:2 (v/v/v) as an optimised mobile phase. Due to the prior separation step, the established calibration curve was found to be more stable than the one calculated from the dissolved amino acids. The found lower limit of detection was 0.01 mg/ml. Finally, this optimised TLC-NIRS method was successfully applied for the qualitative and quantitative analysis of L-lysine in apple juice. NIRS is shown not only to offer a fast, non-destructive detection tool but also to provide an easy-to-use alternative to more complicated detection methods such as mass spectrometry (MS) for qualitative and quantitative TLC analysis of amino acids in crude samples.

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In the bioanalytical era, novel nano-materials for the selective extraction, pre-concentration and purification of biomolecules prior to analysis are vital. Their application as affinity binding in this regard is needed to be authentic. We report here the comparative application of derivatised materials and surfaces on the basis of nano-crystalline diamond, carbon nanotubes and fullerenes for the analysis of marker peptides and proteins by material enhanced laser desorption ionisation mass spectrometry MELDI-MS. In this particular work, the emphasis is placed on the derivatization, termed as immobilised metal affinity chromatography (IMAC), with three different support materials, to show the effectiveness of MELDI technique. For the physicochemical characterisation of the phases, near infrared reflectance spectroscopy (NIRS) is used, which is a well-established method within the analytical chemistry, covering a wide range of applications. NIRS enables differentiation between silica materials and different fullerenes derivatives, in a 3-dimensional factor-plot, depending on their derivatizations and physical characteristics. The method offers a physicochemical quantitative description in the nano-scale level of particle size, specific surface area, pore diameter, pore porosity, pore volume and total porosity with high linearity and improved precision. The measurement takes only a few seconds while high sample throughput is guaranteed.