[show abstract][hide abstract] ABSTRACT: In this study methods for the quantification of baicalin and total baicalein in Scutellariae radix with near infrared (NIR) spectroscopy and attenuated-total-reflectance mid-infrared (ATR-IR) spectroscopy in hyphenation with multivariate analysis were developed and compared. The reference analysis was performed by high performance liquid chromatography coupled to diode array detection (HPLC-DAD). Different pretreatments like standard normal variate (SNV), multiplicative scatter correction (MSC), first and second derivative Savitzky-Golay were applied on the spectra to optimize the calibrations. A principal component analysis was performed with both spectroscopic methods to distinguish wild and cultivated samples. Quality parameters obtained for test-set calibration models of ATR-IR spectroscopy (baicalin: standard error of prediction (SEP)=1.31, ratio performance to deviation (RPD)=2.91 and R(2)=0.88; total baicalein: SEP=1.02, RPD=3.24 and R(2)=0.89) and NIR spectroscopy (baicalin: SEP=1.50, RPD=2.54 and R(2)=0.88; total baicalein: SEP=1.19, RPD=2.76 and R(2)=0.84) demonstrate that both spectroscopic techniques in combination with multivariate analysis are successful tools for the quantification of baicalin and total baicalein in Scutellariae radix, but it was found that ATR-IR spectroscopy provides higher accuracy in the given application. Furthermore it was proved that wild and cultivated samples can be distinguished by ATR-IR.
[show abstract][hide abstract] ABSTRACT: Bladder carcinoma represents more than 4% of all cancer diseases in Austria. The histomorphological evaluation is invasive and remains a subjective and time consuming technique. On account of this it is necessary to find novel non-invasive approaches which support the pathologists for histological recognition to identify malignancy at an early stage. In the present study, Fourier transform infrared (FTIR) microscopic imaging was combined with univariate and multivariate data analysis methods to study bladder carcinoma tissue sections in detail. The possibility to collect IR spectra of bladder carcinoma tissue sections employing an optimized analytical protocol is demonstrated. The correlation between FTIR microscopic imaging and the morphological tissue features obtained by histological staining of the sections demonstrated that many histomorphological tissue patterns can be visualized in the colour images. The routine generation of high quality imaging data is enabled because of the combination of FTIR technology and optimized sample preparation techniques. This opens a new quality of spectroscopic analyses of cancerous tissue, allowing exploration of molecular changes associated with the histopathological morphology.
[show abstract][hide abstract] ABSTRACT: Attenuated-total-reflectance infrared spectroscopy (ATR-IR) and near-infrared diffuse reflectance spectroscopy (NIR) in hyphenation with multivariate analysis was utilized to quantify verbenalin and verbascoside in Verbena officinalis. A new high performance liquid chromatography (HPLC) method as a reference was established and validated. For both vibrational spectroscopic methods test-set and cross validation were performed. Different data-pre-treatments like SNV, 1st and 2nd derivative were applied to remove systematic errors and were evaluated. Quality parameters obtained for the test-set validation revealed that ATR-IR (verbenalin: R(2)=0.94, RPD=4.23; verbascoside: R(2)=0.93, RPD=3.63) has advantages over NIR (verbenalin: R(2)=0.91, RPD=3.75; verbascoside: R(2)=0.80, RPD=2.35) in the given application.
Journal of pharmaceutical and biomedical analysis 05/2013; 84C:97-102. · 2.45 Impact Factor
[show abstract][hide abstract] ABSTRACT: Diamond is known for its high affinity and biocompatibility towards biomolecules and is used exclusively in separation sciences and life science research. In present study, diamond nanopowder is derivatized as Immobilized Metal Ion Affinity Chromatographic (IMAC) material for the phosphopeptides enrichment and as Reversed Phase (C-18) media for the desalting of complex mixtures and human serum profiling through MALDI-TOF-MS. Functionalized diamond nanopowder is characterized by Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectroscopy. Diamond-IMAC is applied to the standard protein (β-casein), spiked human serum, egg yolk and non-fat milk for the phosphopeptides enrichment. Results show the selectivity of synthesized IMAC-diamond immobilized with Fe(3+) and La(3+) ions. To comprehend the elaborated use, diamond-IMAC is also applied to the serum samples from gall bladder carcinoma for the potential biomarkers. Database search is carried out by the Mascot program (www.matrixscience.com) for the assignment of phosphorylation sites. Diamond nanopowder is thus a separation media with multifunctional use and can be applied to cancer protein profiling for the diagnosis and biomarker identification.
[show abstract][hide abstract] ABSTRACT: In the present study, a novel analytical platform is introduced, which enables both analysis and quality control of St John's wort extracts and tissue. The synergistic combination of separation techniques (including thin-layer chromatography (TLC), high-performance liquid chromatography (HPLC)) with mass spectrometry (MS) and vibrational spectroscopy is demonstrated to get deeper insights into the ingredients composition. TLC was successfully employed to identify some unknown ingredients being present in samples with Chinese provenience. On the one hand, the novel HPLC method described here allowed us to clearly differentiate between European and Chinese samples; on the other hand, this method could successfully be employed for the semi-preparative isolation of an unknown ingredient. Matrix-free laser desorption ionization time of flight mass spectrometry (mf-LDI-TOF/MS) using a specially designed titanium oxide layer was employed to identify the structure of the substance. The analytical knowledge generated so far was used to establish an infrared spectroscopic model allowing both quantitative analysis of ingredients as well as differentiating between European and Chinese provenience. Finally, infrared imaging spectroscopy was conducted to obtain knowledge about the highly resolved distribution of ingredients. The analytical platform established so far can be used for fast and non-destructive quantitation and quality control to identify adulteration being of interest according to the Deutsche Arzneimittel Codex (DAC).
[show abstract][hide abstract] ABSTRACT: For sample preparation solid-phase extraction (SPE) became very popular during the 1980s and 1990s. Because method development and its optimization is very time consuming, in most cases C18 is used as standard carrier material without knowing if it possesses the highest efficiency. Therefore detailed studies with different stationary phases are necessary for optimal recovery rates. Due to the resulting high number of samples, automation is of crucial importance. In the study described, the extraction of five monoterpenoids (myrcene, citronellal, p-cymene, menthol and thymol) out of an ethanolic solution was optimized using automated SPE. An automated robotic system, the MEA Personal Purification System® from PhyNexus™ Inc. (http://www.phynexus.com/), was adopted for high-throughput SPE. It allows the simultaneous automatic extraction of 12 samples in parallel employing different carrier materials. Additionally, critical parameters of automation (speed, volume uptake, skipping of drying step) were variegated to obtain optimal recovery rates. Furthermore, extraction efficiency was compared with manual handling to evaluate its performance. The application of 18 different SPE carrier materials, C18 Hydra, C18 ec, C8, C4, C2, C6H5, C6H11 ec, NO2, CN, NH2/C18, Diol, HR-P, EASY, PA, Florisil®, Davisil®, Strata-X® and cellulose pointed out huge differences in extraction efficiency. Finally, the optimized automated procedure was applied for the enrichment of monoterpenoides and their analysis in selected real samples including cough drops, mouthwash and bath additives by gas-chromatography mass spectrometry (GC-MS).
The Open Analytical Chemistry Journal 01/2013; 7:12-21.
[show abstract][hide abstract] ABSTRACT: In the present study, Fourier transform infrared (FTIR) imaging and data analysis methods were combined to study morphological and molecular patterns of St. John's wort (Hypericum perforatum) in detail. For interpretation, FTIR imaging results were correlated with histological information gained from light microscopy (LM). Additionally, we tested several evaluation processes and optimized the methodology for use of complex FTIR microscopic images to monitor molecular patterns. It is demonstrated that the combination of the used spectroscopic method with LM enables a more distinct picture, concerning morphology and distribution of active ingredients, to be gained. We were able to obtain high-quality FTIR microscopic imaging results and to distinguish different tissue types with their chemical ingredients.
Analytical and Bioanalytical Chemistry 10/2012; 404(6-7):1771-8. · 3.66 Impact Factor
[show abstract][hide abstract] ABSTRACT: Oral squamous cell carcinoma (OSCC) of the oral cavity and oropharynx represents more than 95% of all malignant neoplasms in the oral cavity. Histomorphological evaluation of this cancer type is invasive and remains a time consuming and subjective technique. Therefore, novel approaches for histological recognition are necessary to identify malignancy at an early stage. Fourier transform infrared (FTIR) imaging has become an essential tool for the detection and characterization of the molecular components of biological processes, such as those responsible for the dynamic properties of tumor progression. FTIR imaging is a modern analytical technique enabling molecular imaging of a complex biological sample and is based on the absorption of IR radiation by vibrational transitions in covalent bonds. One major advantage of this technique is the acquisition of local molecular expression profiles, while maintaining the topographic integrity of the tissue and avoiding time-consuming extraction, purification, and separation steps. With this imaging technique, it is possible to obtain unique images of the spatial distribution of proteins, lipids, carbohydrates, cholesterols, nucleic acids, phospholipids, and small molecules with high spatial resolution. Analysis and visualization of FTIR imaging datasets are challenging and the use of chemometric tools is crucial in order to take advantage of the full measurement. Therefore, methodologies for this task based on the novel developed algorithm for multivariate image analysis (MIA) are often necessary. In the present study, FTIR imaging and data analysis methods were combined to optimize the tissue measurement mode after deparaffinization and subsequent data evaluation (univariate analysis and MIAs). We demonstrate that it is possible to collect excellent IR spectra from formalin-fixed paraffin-embedded (FFPE) tissue microarrays (TMAs) of OSCC tissue sections employing an optimised analytical protocol. The correlation of FTIR imaging to the morphological tissue features obtained by histological staining of the sections demonstrated that many histomorphological tissue patterns can be visualized in the colour images. The different algorithms used for MIAs of FTIR imaging data dramatically increased the information content of the IR images from squamous cell tissue sections. These findings indicate that intra-operative and surgical specimens of squamous cell carcinoma tissue can be characterized by FTIR imaging.
The Analyst 07/2012; 137(17):3965-74. · 4.23 Impact Factor
[show abstract][hide abstract] ABSTRACT: The Isranalytica, organized by the Israel Analytical Chemical Society, is the largest analytical conference in Israel and has become one of the largest annual conferences in analytical chemistry in the world. Over the past years, Isranalytica has achieved major success and become the most prestigious analytical chemistry meeting in Israel.
[show abstract][hide abstract] ABSTRACT: The measurement of the physical and chemical ("physicochemical") properties of nanomaterials used in industry and science including chemistry, pharmacy, medicine, toxicology, etc., is time-consuming, expensive and requires a lot of experience of a well trained lab staff. Near-infrared spectroscopy (NIR; 4.000-12.000 cm(-1)), working in the wavelength region with the highest IR energy, allows obtaining multifactorial information of the material under investigation due to the occurrence of a high number of combination and overtone vibrations. Coupling of an optimized and well-designed measurement technique with multivariate data analysis (MVA) leads to a non-destructive, fast, reliable and robust novel NIR technique for the fast and non-invasive physicochemical characterization, which is suitable for high-throughput quality control due to the short analyses times of only a few seconds. In the following chapters, the patented basic NIR techniques full-filling these aims are introduced, described, summarized and critically discussed.
Recent patents on nanotechnology. 03/2012; 6(2):135-41.
[show abstract][hide abstract] ABSTRACT: Chinese herbal medicinal (CHM) extracts from fourteen plants were investigated in cell-based in vitro assays for their effect on nuclear factor κB (NF-κB), a key regulator of inflammation, as well as on peroxisome proliferator-activated receptors (PPARs) being key regulators of genes involved in lipid and glucose metabolism. 43% of the investigated CHMs showed NF-κB inhibitory and 50% PPARα and PPARγ activating effects. Apolar extracts from cortex and flos of Albizia julibrissin Durazz. and processed rhizomes of Arisaema sp. and Pinellia ternata (Thunb.) Breit. that effectively inhibited TNF-α-induced NF-κB activation and dose-dependently activated PPARα and PPARγ were further investigated. Bioassay-guided fractionation and analysis by GC-MS led to the identification of fatty acids as PPAR agonists, including linoleic and palmitic acid.
Evidence-based Complementary and Alternative Medicine 01/2012; 2012:983023. · 1.72 Impact Factor
[show abstract][hide abstract] ABSTRACT: This study was designed to investigate the DNA-methylation status of E-cadherin (CDH1) and H-cadherin (CDH13) in serum samples of cervical cancer patients and control patients with no malignant diseases and to evaluate the clinical utility of these markers. DNA-methylation status of CDH1 and CDH13 was analyzed by means of MethyLight-technology in serum samples from 49 cervical cancer patients and 40 patients with diseases other than cancer. To compare this methylation analysis with another technique, we analyzed the samples with a denaturing high performance liquid chromatography (DHPLC) PCR-method. The specificity and sensitivity of CDH1 DNA-methylation measured by MethyLight was 75% and 55%, and for CDH13 DNA-methylation 95% and 10%. We identified a specificity of 92.5% and a sensitivity of only 27% for the CDH1 DHPLC-PCR analysis. Multivariate analysis showed that serum CDH1 methylation-positive patients had a 7.8-fold risk for death (95% CI: 2.2-27.7; p = 0.001) and a 92.8-fold risk for relapse (95% CI: 3.9-2207.1; p = 0.005). We concluded that the serological detection of CDH1 and CDH13 DNA-hypermethylation is not an ideal diagnostic tool due to low diagnostic specificity and sensitivity. However, it was validated that CDH1 methylation analysis in serum samples may be of potential use as a prognostic marker for cervical cancer patients.
International Journal of Molecular Sciences 01/2012; 13(7):8353-63. · 2.46 Impact Factor
[show abstract][hide abstract] ABSTRACT: In this study the potential of new imaging techniques such as Magnetic Resonance Imaging (MRI), Matrix-Assisted Laser Desorption/Ionization (MALDI) profiling mass spectrometry ("MALDI Profiling") and Fourier Transform Infrared (FTIR) spectroscopic imaging was evaluated to study morphological and molecular patterns of the potential medicinal fungus Hericium coralloides. For interpretation, the MALDI profiling, FTIR imaging and MRI results were correlated with histological information gained from Scanning Electron Microscopy (SEM) and Light Microscopy (LM). Additionally we tested several evaluation processes and optimized the methodology for use of complex FTIR images to monitor molecular patterns. It is demonstrated that the combination of these spectroscopic methods enables to gain a more distinct picture concerning morphology and distribution of active ingredients. We were able to obtain high quality FTIR imaging and MALDI-profiling results and to distinguish different tissue types with their chemical ingredients. Beside this, we have created a 3-D reconstruction of a mature Hericium basidioma, based on the MRI dataset: analyses allowed, for the first time, a realistic approximation of the "evolutionary effectiveness" of this bizarrely formed basidioma type, concerning the investment of sterile tissue and its reproductive output (production of basidiospores).
The Analyst 12/2011; 137(7):1584-95. · 4.23 Impact Factor
[show abstract][hide abstract] ABSTRACT: The development of new high throughput methods based on different materials with chemical modifications for protein profiling of complex mixtures leads towards biomarkers; used particularly for early diagnosis of a disease. In this work, diamond-like carbon (DLC) is developed and optimized for serum protein profiling by matrix-assisted laser/desorption ionization mass spectrometry (MALDI-MS). This study is carried out in connection with a material-based approach, termed as material-enhanced laser desorption ionization mass spectrometry. DLC is selected as carrier surface which provides large surface to volume ratio and offers high sensitivity. DLC has a dual role of working as MALDI target while acting as an interface for protein profiling by specifically binding peptides and proteins out of serum samples. Serum constituents are bound through immobilized metal ion affinity chromatography (IMAC) functionality, created through glycidyl methacrylate polymerization under ultraviolet light followed by further derivatization with iminodiacetic acid and copper ion loading. Scanning electron microscopy highlights the morphological characteristics of DLC surface. It could be demonstrated that IMAC functionalized DLC coatings represent a powerful material in trapping biomolecules for their further analysis by MALDI-MS resulting in improved sensitivity, specificity and capacity in comparison to other protein-profiling methods.