Data handling systems

The mass spectrometer (ms) is a common adjunct to a chromatographic system (see Mass spectrometry). The combination of a gas chromatograph for component separation and a mass spectrometer (gc/ms) for detection and identification of the separated components is a powerful tool, particularly when the data are collected usiag an on-line data-handling system. QuaUtative information inherent ia the separation can be coupled with the identification of stmcture and relatively straightforward quantification of a mixture s components. 

Wastewater treatment assistance. Software includes Data Handling System, Lab Dench File, Lab Stock Inventory, Scheduled Work System, Unscheduled Work System, Facility Stock Inventory, Tool Record System, Personnel Record System, Budget Control System, Equipment Record System, and Industrial Pretreaiment File. 

Modern mass spectrometers are interfaced with computerized data-handling systems capable of displaying the mass spectrum according to a number of different formats. Bar graphs on which relative intensity is plotted versus m z are the most common. Figure 13.40 shows the mass spectrum of benzene in bar- graph form. 

Apparatus. A gas chromatograph equipped with a flame-ionisation detector and data-handling system. The use of a digital integrator is particularly convenient for quantitative determinations, but other methods of measuring peak area may be used (Section 9.4). 

Note As is often the case, the HPLC system will be under computer control, which is likely to be part of a data-handling system. Since the data generated from the OQ hardware tests typically require chromatographic data handling, the data-handling software should be validated beforehand. The data-handlingfLC control software installation and IQ/OQ implementation, which are not addressed in this chapter, may take a considerable amount of time. This is often the case since this process typically involves an initial client/server implementation. 

The LC control software, either stand-alone or as part of an overall data-handling system, should be tested by means of a separate OQ protocol. This protocol only needs to address the communica-tions/control integrity of the hardware (e.g., setting up a run/sequence with the proper instrument parameters, the ability to start and stop the pump, etc.). It should cover all the required instrument control functions listed as part of the protocol s functional specifications. It does not need to include specific hardware performance testing, such as linearity or flow rate. The latter tests are performed separately, as part of the individual hardware validation described below. 

As with any data generation or data-handling system, appropriate validation (instrument qualification (IQ)/operational qualification (OQ)/performance qualification (PQ)) is required to demonstrate that the system is accurately and reliably performing in accordance with the user-functional requirements. 

Computerised data handling systems will generate reports including a number of system suitability parameters. Figure 10.11 shows a chromatogram with a report form appended. In order for the report to be generated, the computer has to be given... 

With commercially available automatic sampling devices, large numbers of samples can be routinely analyzed by LC without operator intervention. Such equipment is popular for the analysis of routine samples (e.g., quality control of drugs), particularly when coupled with automatic data-handling systems. Automatic injectors are indispensable in unattended searching (e.g., overnight) for chromatographic parameters such as solvent selectivity, flow rate, and temperature optimization. 

HPLC system consisting of a buffer pump, preferably with degasser, autosampler with cooling system, fluorescence detector (excitation 384 nm, emission 516 nm) and an integration and data handling system. 

Tandem mass spectrometer with HPLC pump, analytical column (LC-18S, 200 x 4.6 mm Supelco 59630), autosampler and data-handling system. 

Fig. 2 Postcolumn derivatization scheme for aflatoxin analysis 1, mobile phase 2, HPLC pump 3, injection valve 4, precolumn 5. analytical column 6, derivatizing agent solution 7, auxiliary HPLC pump 8, T-valve 9, oil or water bath 10, reaction coil 11, fluorescence detector 12, waste 13, chromatographic data handling system.

Qualified and calibrated equipment, including robotic methods Validated LIMS, computer programs for calculation, and other data-handling systems... 

Speed of Analysis. The speed with which many immunochemical analyses can be completed illustrates a major advantage of immunochemical procedures. Immunochemical assays are most time and cost effective when the sample load is large. Parker (4) estimated that a single technician could perform 100-5000 radioimmunoassays per day with little or no assay automation in comparison to 20-40 GLC assays (3). Numerous inexpensive systems are available to decrease analysis time. These systems may include solid phase separation techniques, automatic dispensers, test tube racks which will fit directly into a centrifuge and/or scintillation counter, and data handling systems. Alternatively, there are fully automated systems based on RIA or ELISA which require very little operator attention and which handle 25-240 samples/hr. Gochman and Bowie (81) have outlined the basis of operation and summarized the features of automated RIA systems and extensive literature is available from the manufacturers. 

Data System Setup Set the integrator or computerized data-handling system as its respective manual instructs for normal gel permeation chromatographic determinations. Set the integration time to 15 min. 

The data acquisition/data handling system consists of a multichannel scalar (MCS) and a computer system. Signal pulses from the detector accumulate into memory channels of the MCS according to their M/Z ratios. Signal pulses from replicate scans are sorted into the appropriate channels and accumulated until the analysis of that sample is complete. A computer program retrieves the totals from the MCS memory and stores the data for later manipulation or display. 

A typical IR spectrometer consists of the following components radiation source, sampling area, monochromator (in a dispersive instrument), an interference filter or interferometer (in a non-dispersive instrument), a detector, and a recorder or data-handling system. The instrumentation requirements for the mid-infrared, the far-infrared, and the near-infrared regions are different. Most commercial dispersive infrared spectrometers are designed to operate in the mid-infrared region (4000-400 cm ). An FTIR spectrometer with proper radiation sources and detectors can cover the entire IR region. In this section, the types of radiation sources, optical systems, and detectors used in the IR spectrometer are discussed. 

A successful chromatographic analysis depends on the precise performance of the HPLC instmmentation, i.e., control of pressure, the composition of mobile phase, the performance of the analytical column, the detector, the injector or autosampler, and the electronic data handling system. 

Fourier transform infrared (FT-IR) spectroscopy is now one of the most popular techniques in analytical chemishy, this technology having several advantages compared to conventional dispersive infrared inshuments. Developments in instrument hardware, in computer software (usually by the instrument manufacturers) and in computing power generally has resulted in very powerful data collection and data handling systems for the analysis and characterisation of all sorts of materials including colorants. 

Used in conjunction with a state-of-the-art data handling system and reference library, the FTMS is capable of meeting all microelectronic service laboratory mass spectrometry needs. 

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