Analysis at-line

Chromatography. GC is the most common anal)d ical method used but liquid and supercritical fluid chromatographic methods are being increasingly developed. Like titration the sample is destroyed in the analysis process. The ideal situation depicted in Figure 8.8 cannot normally be applied for titration or chromatographic analysis since the analysis equipment needs to be close to the sampling device. This is often termed at-line analysis. 

Other forms of analytical investigations may also be applied, such as at-line analysis (discontinuous direct analysis of objects, e.g., noninvasive blood glucose monitoring) and trans-line analysis (remote sensing, teleanalysis). 

M.D. Mowery, R. Sing, J. Kirsch, A. Razaghi, S. Bechard and R.A. Reed, Rapid at-line analysis of coating thickness and uniformity on tablets using laser induced breakdown spectroscopy, J. Pharm. Biomed. Anal, 28, 935-943 (2002). 

Off-line chemical analysis in labs to a large extent snbstitnted by at-line analysis - e.g., spectroscopy, fast chromatography, imaging, and sensor arrays. Mnltivariate calibration nsed to convert PAT data to traditional space (e.g., concentrations, disintegration rate). 

Analytical interfaces are integrated into the AuMpRes set-up for at-line analysis by sampling and subsequent chromatography (HPLC) [108], Moreover, this allows online analysis by infrared or Raman spectroscopy. Real-time monitoring of the chemical processes can be achieved via spectroscopic measurements, for which suitable optical flow-through cells have to be installed at selected positions of the micro reaction system. 

Processing/industrial Process monitoring and control, quality control, workplace monitoring, waste stream monitoring In-line/at-line analysis, real time monitoring, designed to be smart sensors... 

Two other commercially available in-process Raman systems have been developed by Kaiser for on-line or at-line analysis of powders, slurries and other types of process samples. The hrst is the RamanRxn3 PAT Analyser, which can be wall-mounted or put on wheels for use in a laboratory or plant situation. It can be coupled with multiple probes, which themselves can be a noncontact or immersion type. It is self-calibrating. The second system is the PhAT System Raman Analyser, which is smaller in size, much more portable and developed mainly for analysing solids in pilot scale manufacturing. 

Detailed description of all aspects of the application of atomic spectrometry to analysis of the huge variety of sample matrices associated with industrial processes is clearly outside the scope of this chapter and so only a brief overview is given of each application area. For detailed discussion of the application of atomic spectrometry in industrial analysis, the reader should refer to the annual reviews of this topic published in Atomic Spectrometry Updates in conjunction with J.Anal. At. Spec-trom., [3-12]. In Section 20.2, specific applications of atomic spectrometry to online/at-line analysis are discussed in more detail. 

An area that will become increasingly important is the use of infrared spectroscopy for online and at-line analysis. Most of the novel applications of FTIR to industrial process analysis are proprietary. An example that illustrates the advantages of process FTIR is... 

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