Automatic instruments, development

In an automatic instrument developed by Lidzey and Stockwell [19] for the analysis of ftirftiraldehyde in gas oil, a preliminary separation is performed on a GC column coupled to a specific colorimetric reagent in a continuously flowing hquid stream. A back-flushing... 

The realization of sensitive bioanalytical methods for measuring dmg and metaboUte concentrations in plasma and other biological fluids (see Automatic INSTRUMENTATION BlosENSORs) and the development of biocompatible polymers that can be tailor made with a wide range of predictable physical properties (see Prosthetic and biomedical devices) have revolutionized the development of pharmaceuticals (qv). Such bioanalytical techniques permit the characterization of pharmacokinetics, ie, the fate of a dmg in the plasma and body as a function of time. The pharmacokinetics of a dmg encompass absorption from the physiological site, distribution to the various compartments of the body, metaboHsm (if any), and excretion from the body (ADME). Clearance is the rate of removal of a dmg from the body and is the sum of all rates of clearance including metaboHsm, elimination, and excretion. 

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. 

Besides understanding the philosophy and concepts of automatic instrumentation, it is necessary to make a clear economic assessment of the advantages to he gained from the introduction of automation. There can he no substitute for practical experience in solving such problems. The field is wide, so a complete review is not practical. Some developments are described here to stimulate the reader into deeper research. It is important to evaluate the various developments that have become available through both large and small instrumentation companies. 

Table 1.2 gives some of the reasons for the LGC setting up its automation team. The primary motivation was economic. LGC was often subject to constraints on staffing in parallel with large increases in analytical commitments. The introduction of cost-effective analyses, using mechanical or automatic instruments, reduces staff involvement and allows well qualified people to be released for the development of new analytical requirements. The analysis of beer samples by multi-channel continuous flow analyser [S, 6, 7] and the introduction of a mechanical solvent extraction and identification system to analyse and measure levels of quinizarin in gas oil, both for duty purposes, were prime examples [8], Both systems involved commercially available components and/or instruments integrated with modules designed and built in-house. 

Examples include the development of more sensitive and reliable automatic instrumentation for monitoring chemicals, radiation and biological materials in the environment, of safety-or-environment-related add-on equipment for vehicles, of pollution-control technology and of safety-related equipment for use in industry, mining and the home. 

Other Methods. Marion et al. used a competitive ELISA to measure the specificity of anti-DNA antibodies. Low-affinity, low-avidity antibodies bind to competitor DNAs in solution and thus cannot bind to solid-phase DNA subsequently (M7). A new automatic instrument platform using the immunofluorescence method (EliA ) to detect anti-dsDNA has recently been developed. We found that results from this method correlated well with results from the ELISA method (unpublished). 

An instrumental form of multiple development is referred to as programmed multiple development. The sorbent is heat dried between each development. A instrumental variation is referred to as automatic multiple development. In this case, the mobile phase is removed from the developing chamber and the sorbent dried under vacuum. These techniques have been reviewed recently [27,45]. 

Shikata, Masuzo — (Aug. 10,1895, Tokyo, Japan - May 8, 1964, Kyoto, Japan) In 1920 Shikata graduated from the Department of Agricultural Chemistry of the Imperial University of Tokyo. In 1922 he went to Europe, and the next year joined - Heyrovsky, J. in Prague, Czechoslovakia. In 1924 Heyrovsky and Shikata [i] developed the first - polarograph - the first automatic instrument to record current-potential dependencies of a - dropping mercury electrode. For this invention, Heyrovsky was awarded the Nobel Prize in Chemistry in 1959. In 1924 Shikata was appointed Professor of the Imperial University of Kyoto (presently Kyoto University). In 1942 he was appointed Vice-President of the Research Institute of... 

The schematics of the instrument installation are shown in Fig. 9.13. The RADAIR instrument develops readouts on 4 continuous measuring channels of activity concentrations of artificial a, P, emitters and natural radon in Bq m and of the ambient y dose in pGy h. These activity concentration readouts are divided from countings in 1000 s cycles, of the activity deposited on the filter taken from samples of the surrounding air. The filter automatically advances after remaining 24 hours in front of the stack of two semiconductor detectors. The first detector located above the filter, delivers a net counting rate in proportion to the activity deposited on the filter. The... 

I, and I. Radioimmunoassay combines the specificity of an immunochemical reaction with the sensitivity of isotope analysis (F4, S19) and is currently developing rapidly for the analysis of steroids, peptide hormones, and specific proteins (G9). Enzymes can be determined with labeled substrates (01). The requirements of standardization and dosimetry make it probable that these methods will continue to be based on relatively large automatic instruments. However, the greatest problems are unlikely to be in the counting equipment but in sample handling and processing and in standardization of the system. 

In order to eliminate the disadvantage, automatic devices have been developed for slit-beam densitometers which can scan a track several times 25,26). Distance and number of scan courses as well as the distance of the sample tracks are entered into the automatic instrument in advance. The highest value derived from scanning a track repeatedly is adopted as measuring value for each spot. This method of scanning is, unfortunately, time consuming. 

The first fully automated instrument for chemical analysis (the Technicon Auto Analyzer ) appeared on the market in 1957. This instrument was designed to fulfill the needs of clinical laboratories, where blood and urine samples are routinely analyzed for a dozen or more chemical species. The number of such analyses demanded by modern medicine is enormous, so it is necessary to keep their cost at a reasonable level. These two considerations motivated the development of analytical. systems that perform several analyses simultaneously with a minimum input of human labor. The use of automatic instruments has spread from clinical laboratories to laboratories for the control of industrial processes and the routine determination of a wide spectrum of species in air, water, soils, and pharmaceutical and... 

Evaluation of the performance of a method or an instrument represents the largest use of CRMs. Examples are widely reported in the literature. One could even say that the development of a new method or instrument without evaluation of the performances with (a) CRM(s) is an incomplete task. Besides these research tasks, CRMs for calibration or validation are also used to assess the performance of instruments by the manufacturer himself to demonstrate the possibilities of his instrument or by the customer who wishes to evaluate the proposed instrument before purchasing it. CRMs produced by independent official or regulatory bodies to validate instrument performance or calibration sets have been under development for several years. They have in particular allowed the solution of inaccuracy problems in the biomedical sector where calibration test kits of automatic instrument manufacturers were not comparable and even led to different results between countries such arguments supported many BCR projects for... 

The on-line instrumentation development needs can be divided along the traditional lines of quality control and process control instrumentation The interrelationship between the two and the proposed mode of interaction are shown in Figure 9 The quality control instruments, in an operational and a practical sense, are located outside the preparation plant As a result of data obtained on product quality, the quality control instrument interacts with the plant feed and the process control instrumentation to optimize the use of raw material consistent with the desired product specifications This feedback loop can be automatic however, current practice places the preparation plant superintendent or engineer in the loop and the quality control measurement in a remote laboratory, resulting in manual control scheme with a long time delay The process control instrumentation controls a single unit operation and the instrumentation is unique to each unit operation Their set points are established by the output from the quality control Instruments ... 

A further type of fast automatic ellipsometer for electrochemical investigations has been described [933] and an experimental approach to observe fast transients with ellipsometry was reported [934]. In the photometric mode, the intensity of the reflected light is measured as a function of the position of polarizer and sometimes compensator in the incoming beam for further details and an overview, see [934]. A general overview of instrumental developments has been provided [935]. 

Immunochemical methods are routinely used in the clinical laboratory on account of their special features, particularly their high selectivity and the commercial availability of automatic instrumentation for their implementation. Since the earliest immunoassay involving radioisotopes was reported, a large variety of alternative immunoassays have been developed to circumvent the shortcomings of radioimmunoassay, many of them using fluorescence detection. Some fluoroimmunoassays (FIAs) developed with this purpose, such as fluorescence-quenching... 

Automated multiple development (AMD), providing automatic chromatogram development and drying, is a novel form of the PMD technique. Automated multiple development as an instrumental technique can be used to perform normal-phase chromatography with solvent gradients on HPTLC plates. Most of the AMD applications use typical gradients Starting with a very polar solvent, the polarity is varied by means of base solvent of medium polarity to a... 

The electronic age was marked by the advent of the vacuum tube. This enabled the construction of highly accurate and versatile automatic instruments. Perhaps the first impact was on potentiometric methods, especially to pH measurements using the glass electrode. Although the glass electrode was known as early as 1909 it was only after the development of vacuum tube voltmeters around 1935 that it was used for practical pH measurements ( ). 

There are now several types of automatic osmometers that operate with essentially zero flow and that reach equilibrium very rapidly, usually within minutes. Osmotic equilibrium depends on an equal and opposite pressure being developed. The critical part of their design relates to the method of automatic adjustment of the osmotic pressure of the solution side so that the activity of the two sides is equal. Since several concentrations usually need to be run, the time required to determine a molecular weight by osmometry has been reduced from a week to a few hours by these automatic instruments. 

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