Sample pretreatment is the most important procedure to remove the matrix for interfacing with mass spectrometry (MS). Additionally, for the samples with low concentration, the process of preconcentration is required before MS analysis. We have newly developed a solid-phase extraction stationary phase based on C60-fullerene covalently bound to silica for purification of biomolecules of different characteristics. Silica particles of different porosity are modified with aminopropyl linker and then covalently bound to C60-fullerenoacetic acid or C60-epoxyfullerenes. The developed materials have been successfully applied as an alternative to commercially available reversed-phase materials for solid-phase extraction. C60-fullerene silica is able to retain small and hydrophilic molecules like phosphopeptides, which can be easily lost by reversed-phase sorbents. The novel materials are applied for desalting and preconcentration of proteins and peptides, especially phosphopeptides. In addition, the C60-fullerene silica is applied for the solid-phase extraction of selected flavonoids with recoveries of approximately 99%. The recoveries are compared with the commercially available solid-phase extraction materials.

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.

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A key risk factor in the development of atherosclerosis is a high concentration of serum low density lipoprotein (LDL)-cholesterol. The main purpose of this study was to assess the LDL and high density lipoprotein (HDL) content in human serum by employing near-infrared (NIR) spectroscopy and multivariate calibration techniques. Initially a qualitative principal component analysis (PCA) based cluster model was generated to evaluate the feasibility of NIRS for classifying and identifying the LDL and HDL-cholesterol. Therefore TiO(2) beads were used as an adsorbent for selectively immobilizing LDL and HDL-cholesterol and further analysing the incubated and washed samples via NIR diffuse reflection spectroscopy. A principle component regression (PCR) model of 24 LDL standards in a range from 500 - 3000 ppm (clinical value is 1500 ppm) and a partial least squares regression (PLSR) model of 25 HDL standards in a range from 100 - 1000 ppm (clinical value is 400 ppm) were computed. Furthermore, the wavenumber region between 4000 cm(-1) and 7240 cm(-1) was found comprising the main spectral information regarding the TiO(2)-LDL and TiO(2)-HDL composites. The regression coefficients (r) for LDL and HDL were > 0.99 (calibration curve) and > 0.97 (validation curve), respectively. The PCR model of TiO(2)-LDL showed a standard error of estimation (SEE) of 122.80 ppm and a standard error of prediction (SEP) of 121.15 ppm while the PLSR model of TiO(2)-HDL showed 47.70 and 47.14 ppm, respectively. In order to determine the concentration of HDL in real serum samples, LDL was removed by adding a precipitation reagent containing 10 mg/mL magnesium dextran-sulfate, followed by incubation and centrifugation. The pretreated serum samples were predicted by the PLSR model while the standard deviation (SD) from the reference to the NIR predicted values of six test samples in a concentration range from 500 - 2500 ppm showed < 10 %. These results indicate the usefulness of the NIR spectroscopy (NIRS) as a potential alternative or even supplementary clinical method for the quick determination of LDL and HDL in human serum.