Analysers robotic

In the last several years, on-line extraction systems have become a popular way to deal with the analysis of large numbers of water samples. Vacuum manifolds and computerized SPE stations were all considered to be off-line systems, i.e., the tubes had to be placed in the system rack and the sample eluate collected in a test-tube or other appropriate vessel. Then, the eluted sample had to be collected and the extract concentrated and eventually transferred to an autosampler vial for instrumental analyses. Robotics systems were designed to aid in these steps of sample preparation, but some manual sample manipulation was still required. Operation and programming of the robotic system could be cumbersome and time consuming when changing methods. 

Analytical processes performed by DAAs are similar to those carried out manually. Hence, they allow readier adaptation of manual methods than do continuous analysers insofar as the latter require stricter optimization of the different chemical and physico-chemical variables involved. As can be seen from Fig 8.2, of the three types of automatic analysers, robotic types bear the strongest resemblance to manual configurations. 

Table 4.15 fists the many possibilities for solid sampling for GC analysis. In general, sample preparation should be considered in close conjunction with injection. Robotic sample processors have been introduced for automatic preparation, solvent extraction and injection of samples for GC and GC-MS analyses. Usually, facilities are included for solvent, reagent, and standard additions and for derivatisation of samples. 

The above system of directly sensing a process stream without more is often not sufficiently accurate for process control so, robot titration is preferred in that case by means of for instance the microcomputerized (64K) Titro-Analyzer ADI 2015 (see Fig. 5.28) or its more flexible type ADI 2020 (handling even four sample streams) recently developed by Applikon Dependable Instruments20. These analyzers take a sample directly from process line(s), size it, run the complete analysis and transmit the calculated result(s) to process operation (or control) they allow for a wide range of analyses (potentiometric, amperometric and colorimetric) by means of titrations to a fixed end-point or to a full curve with either single or multiple equivalent points direct measurements with or without (standard) addition of auxiliary reagents can be presented in any units (pH, mV, temperature, etc.) required. 

The Rosetta mission with its planned landing on a comet, with analysis of cometary material (see Sect. 3.2), should provide more information on the occurrence of chiral molecular species in the cosmos (Adam, 2002). The GC-MS apparatus installed in the robotic lander RoLand is also able to separate and analyse chiral organic molecules (Thiemann and Meierhenrich, 2001). 

Automation at its basic level can be expressed simply with the statement that analyses that were traditionally manually performed are now performed mechanically through computer-controlled robotics or workstations. Designers typically have a strong desire to exactly reproduce the manual process. In reality, minor changes to the manual approach must be made in order to make the automated process reliable and efficient. 

Walk-up capability could be provided for customers by robots which could read procedures and sample designations from bar codes and perform and report the corresponding analyses. 

There are signs that companies are becoming increasingly aware of the industrial market and some attempts have been made to develop a systematic approach to this problem. Whereas in chnical chemistry the matrix is usually blood or urine, in the industrial area there are many varied matrices. The volume of sales for any matrix is often insufficient to justify the development investment required. An alternative philosophy is needed to meet the requirements economically. The Mettler range of automatic instruments provides one example of a systematic approach to automate a range of analysers. More recently the Zymark Corporation (Zymark Center, Hopkinton, Massachusetts, USA), in the introduction of its Benchmate products, has defined procedures which can be tailored to individual laboratory needs by using essentially similar modules. These modules are coordinated with a simphfled robotic arm. Several tailor-made systems have been developed which have a wide appeal and are easily configurable to particular needs. 

Fig. 2.9 The Cobas Fara II robotic centrifugal analyser. Reproduced with permission of Roche Diagnostics.

In an attempt to understand the factors which lead to a successful and acceptable implementation of a robotic system, Molet et al. [2] have described the history of the implementation of a robotic installation in the steel industry in France. TTiey analysed the reactions of the various participants. Most of the difficulties encountered were related to the technological modifications required in the plant to install the robot and its peripheral equipment, and the labour and organizational changes which affected those most directly involved. TTiis experience provides some general lessons about the dos and do nots of rohotization (see also Besson [3] and Guest [4]). 

Robotics has been defined by Zenie [S] as an extension of programmable computers to do physical work, as well as processing data. Instrument systems using robotization and programmable computers are currently being used to improve productivity in scientific laboratories. Analysts need to identify samples, weigh, dilute, concentrate, extract, filter, evaporate, manipulate and analyse them. 

Many automated analytical instruments have been used to reheve laboratory technicians from routine work and thus increase their productivity. These instruments are well suited to hospital and factory laboratories, where the same analyses are performed every day. In more sophisticated laboratories, especially research laboratories, where the day-to-day analyses change, amore versatile instrument is needed. Robots in these laboratories will solve the problems arising from the non-versatility of automated instruments. The ability of a robot to do repetitious or dangerous work, with little or no external intervention, allows almost continuous generation of data and thus increases productivity, while decreasing the costs associated with having a human do the same work. 

The first robotically controlled microwave decomposition system was developed at Kidd Creek Mines in Canada. This first application described by Labrecque [23] was developed for the decomposition of geological samples in order to analyse the matrix and trace elements. 

Lester et al. [24] have described a robotic system for the analysis of arsenic and selenium in human urine samples which demonstrates how robotics has been used to integrate sample preparations and instrument analysis of a biological matrix for trace elements. The robot is used to control the ashing, digestion, sample injection and operation of a hydride system and atomic absorption instrument, including the instrument calibration. The system, which routinely analyses both As and Se at ppb levels, is estimated to require only... 

The quahty of the precision, accuracy, and MDL are comparable for the robotic and manual methods. A greater number of samples can be analysed in a faster turnaround time. Staff have also been freed from the mundane chores associated with these analyses for more demanding and rewarding tasks. 

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