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Portable Raman spectroscopy is an invaluable tool in the study of archaeological sites, allowing for in situ analysis which minimizes the impact of such studies on important cultural sites. The flexibility of the use of a fiber optic probe and tripod-mounted video microscope with a light weight instrument reduces the need for sampling, and increases the ability to make representative measurements over what can be very large sample areas. The information content of Raman spectroscopy aids in the understanding of the materials used in the construction and restoration of important archaeological sites, and in understanding the degradation that is occurring which should aid in preservation and restoration work.

For SERS developers and end users of SERS for specific applications to investigate low concetation levels of compounds, the centerpiece of their technological platform must be a Raman setup that provides reliable lab grade performance and is affordable and portable, allowing them to tackle real world problems. The portable i-Raman Plus system coupled with a BAC151 video microscope sampling accessory provides an ideal setup. With the performance and flexibility of use with different laser spot size and power for SERS research.

Raman spectroscopy is an advantageous analytical tool that allows for the measurement of molecular structure and identifying chemical composition of materials based on the rotational and vibrational modes of a molecule. With advanced technology and an optimized optical design, the B&W Tek BAC102 series E-grade probe can access lower frequency modes down to 65 cm-1, providing key information for applications in protein characterization, polymorph detection, and identification, along with material phase and structure determination.

Portable Raman is used to quantify trigonelline, an alkaloid that contributes to the health benefits of some foods. A simple method to quantify the presence of diluted trigonelline in solutions using surface enhanced Raman spectroscopy is described. Portable Raman is a tool that could be used in quality control of food items such as coffee and quinoa.

Correct identification of mineral phases in rock thin sections is essential to petrographic and petrologic analysis of rocks. Portable Raman coupled to an optical microscope gives chemical information along with the optical images to give a higher certainty of identification than traditionally used optical micropcopy alone.

This work was carried out with a Metrosep C 2 - 150 separation column, the following eluent parameters being investigated: nitric, tartaric, citric and oxalic acid concentration and concentration of the complexing anion of dipicolinic acid (DPA). The aim was to determine the effect of these parameters plus that of the column temperature on the retention times of alkali metals, alkaline earth metals, ammonium and amines using ion exchange chromatography with non-suppressed conductivity detection. Due to similar affinities for the ion exchange column, transition metals are difficult to separate with the classical nitric, tartaric, citric and oxalic acid eluents. Partial complexation with the dipicolinate ligand significantly shortens the retention times and improves the separation efficiency. However, too strong complexation results in a rapid passage through the column and thus in a complete loss of separation. Apart from a change in the elution order of magnesium and calcium at high DPA concentrations, other non-amine cations are only slightly affected by the eluent composition. Irrespective of the tartaric acid and nitric acid concentration in the eluent, an increase in column temperature shortens the retention times and slightly improves the peak symmetries of organic amine cations, particularly in the case of the trimethylamine cation. In contrast, an increase in column temperature in the presence of DPA concentrations exceeding 0.02 mmol/L increases the retention time of the transition metals. Depending on the separation problem, variation of the pH value, the use of a complexing agent and/or an increase in column temperature are powerful tools for broadening the scope of cation chromatography.

Metrohm's iColumns are the first IC columns that are equipped with a data chip that stores freely definable data, fixed column data as well as data entered by the MagIC NetTM software. Any relevant information such as column type, standard parameters, maximum pressure, etc. can be called up at any time. Analysis data continuously entered by the MagIC NetTM software guarantees a complete column and GLP-compliant surveillance irrespective of the IC system in which the column is operated. The MagIC NetTM software surveys the critical column data and indicates any infringement of limits.

By using the 800 Dosino and the 849 Level Control as the only additional devices, Metrohm`s intelligent ion chromatography (IC) systems - the 850 Professional IC and the Compact IC family - can be easily extended to perform any unattended inline eluent preparation. Fully controlled by MagIC NetTM, the 849 Level Control monitors the eluent level while the Dosino performs all dosing and liquid handling tasks. Consecutive injections of a 250-µg/L standard over approximately 20 days revealed an excellent retention-time stability. After more than 800 consecutive injections, relative standard deviations for anions (F-, Cl-, NO2-, Br-, NO3-, PO43-, SO42-) and cations (Li+ , Na+, NH4+, K+, Ca2+, Mg2+) were smaller than 0.55 and 0.41%, respectively. In the case of a 24-hour sequence, retention-time precision for anions and cations was better than 0.09 and 0.08%, respectively. The presented inline eluent preparation system increases the retention-time reproducibility and allows the determination of anions and cations over a one-month period without manual eluent preparation.

Comparative measurements show that the new Metrosep C 4 cation column has even better separation characteristics than the previous Metrosep C 2 and Metrosep Cation 1-2 column types. The Metrosep C 4 column has a clearly improved peak shape which leads to a better separation of the individual peaks. Using Metrosep C 4 the number of theoretical plates per meter was noticeably higher than that obtained on the Metrosep C 2 or C 1-2 column. Additionally for standard cations transition metals and amines, the Metrosep C 4 column shows better results with respect to peak shape, peak height, resolution and asymmetry factor. The clearly improved resolution of the C 4 column with its narrow and high peaks achieves baseline separation for six standard and six transition metal cations. Analysis times and peak areas obtained with the C 4 column are in the same range as those obtained with its predecessors.As a result of the latest production methods and materials, the promising Metrosep C 4 column excels by an outstanding separation performance for complex mixtures comprising standard cations, transition metal cations and amines.

The combination of 850 Professional IC, 858 Professional Sample Processor, Dosino and MagIC NetTM software offers a variety of automated ion chromatographic sample preparation and calibration techniques available as an anion, cation or dual channel system. Calibration is straightforward and requires only one multi-ion standard.Inline calibration allows the calibration of any standard concentration in the ppt range by using one single stable standard solution at the ppb level. By using a preconcentration column and switching the valves one, two or more times different calibration concentrations at the ultra-trace level can be created with unprecedented reproducibility. The inline preconcentration technique uses a pre-concentration column and is ideally suited for trace analysis in complex matrices, especially when combined with matrix elimination. Besides facilitating the preparation of g/L to ng/L calibration graphs Metrohm`s intelligent techniques are capable of logical decision making. While Metrohm`s intelligent Partial Loop technique (MiPT) allows samples with a wide concentration range to be injected without previous manual dilution, the intelligent inline dilution technique, after the first sample injection, compares peak areas, calculates, if necessary, the dilution factor, dilutes and automatically re-injects the sample. The presented inline techniques allow the rationalization of the time-consuming, error-prone and cost-intensive manual preparation of standard solutions. They guarantee that the determined sample concentrations always lie within the calibration range. Higher sample throughputs as well as lower analysis costs and improved data reliability are achieved.