Evaluation tools chromatography

Sucrose quantitation has also been performed by colorimetric methods. However, in recent years, automated enzymatic analyzers and instmmental methods (eg, ion chromatography and hplc) have become increasingly popular, as they provide greater sensitivity and accuracy. Near infrared (nir) spectroscopy is currendy under evaluation as a tool for sucrose quantitation in sugar mills and food processing operations. 

Method development and optimization are started with review of the currently available methods within the company or in literature. Available methods are used as a starting point and evaluated against the method requirements set in the method definition. If necessary the method is optimized or redeveloped in order to fulfill the requirements. DOE tools (response surface design) are preferentially applied to obtain the best optimal conditions in terms of robustness. Application of DOE methodology is not new in chromatography and DOE is frequently applied also for enantiomeric separations in Especially in... 

Bernreuther A, Schreier P, Multidimensional gas chromatography-mass spectrometry A powerful tool for the direct chiral evaluation of aroma compounds in plant tissues, II, Linalool in essential oils and fruits PhytochemAnall. G7— 7(), 1991. 

Hydrophobic chromatography is still a relatively new technique for the biochemist and many fundamental aspects remain to be solved before the true value of these procedures can be evaluated. However, initial experiments indicate that the technique will prove to be another valuable tool in protein separations. In contrast to affinity chromatography, where specific supports must be designed for each application, it appears that a limited number of supports should suffice for a wide range of applications. 

A number of companion techniques have been shown to be useful and merit further use. These include NMR, IR, MS, GC-MS, AA, X-ray microscopy, and GPC. ESR has not been appreciably utilized as a companion technique but may be considered, particularly with polymers containing ESR-sensitive metals. Gel permeation chromatography (GPC) should be considered as a companion tool for thermal degradation evaluations where depolymerization is suspected. There is a need for a number of well-chosen thermal analysis studies of both the volatile products by TG-MS, etc. (for both chemical and toxicological purposes) and the residue. Such studies should occur throughout the studied temperature range rather than just at the room and final temperatures. 

The models were mainly used to size shared resources (e.g., chromatography columns, utilities, and media/buffer preparation tanks) and evaluate various capacity scenarios. The impact of different shift patterns on equipment demand for buffer preparation was also evaluated. Using such tools makes it easier to quantify the trade-off between labor cost and capital investment. The model was able to generate different options based on different work organizations. For example, two options were explored ... 

Inununoassay and GC/MS (gas chromatography/mass spectrometry) analysis for triazine herbicides were compared in order to evaluate the potential of Inununoassay as a screening tool. Water samples were collected at 146 sites on streams In a 10-state region of the midwestern United States during 1989 before and shortly after application of pre-emergent herbicides that were used for weed control in the production of corn and soybeans. The sites were sampled a third time in fall 1989 during a low streamflow period. 

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