Batch analysers without final transfer

In these DAAs, ail operations —signal measurement included— are carried out in the same vessel. There are a large number of commercially available analysers of this type. A comprehensive description of them is beyond the scope of this book, so only three representative muiti-parameter, non-specific examples are commented on here. 

It is significant that Technicon, the pioneering and virtually exclusive developers of continuous automatic analysers, have recently devoted their production efforts to batch models. Probably, their RA-1000 model was created to compete with the centrifugal analysers introduced by other firms and which were gradually displacing continuous-flow AutoAnaiyzers, widely used until a decade or so. 

The RA-1000 is a compact, computer-controlled analyser consisting of three discs (Fig.8.8a)  

The system uses high-precision Hamilton pipettes to transfer samples (3-20 pl ) and reagents (300 pL) to the central reaction tray. Some inert fluid TRAF, the instrument s most significant innovation, is used to avoid carryover. Each parameter is measured In a single cuvette thus, if five parameters per sample are to be determined, the instrument capacity will be 20 

The microprocessor exerts control over (a) the number of parameters determined per sample (b) the type of analysis to be applied In each instance 

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A typical example of batch analyser without final transfer using ordinary cuvettes is the Technicon Model RA-1000. As can be seen from Fig. 8.10, it consists of a central unit with 100 disposable cuvettes receiving samples and reagents from two additional trays. A computer controls all the instrument functions, acquires data and presents the final results once processed. This analyser is suitable for both kinetic and end-point measurements and can perform emergency analyses without significantly altering Its functioning. 

There are batch analysers without final transfer suitable for Immunoassays, such as the ELISA Processor II and the Behring Analyser Nephelometer, both manufactured by Behrlngwerke. 

The work is organized in two parts in the first part kinetics is presented focusing on the reaction rates, the influence of different variables and the determination of specific rate parameters for different reactions both homogeneous and heterogeneous. This section is complemented with the classical kinetic theory and in particular with many examples and exercises. The second part introduces students to the distinction between ideal and non-ideal reactors and presents the basic equations of batch and continuous ideal reactors, as well as specih c isothermal and non-isothermal systems. The main emphasis however is on both qualitative and quantitative interpretation by comparing and combining reactors with and without diffusion and mass transfer effects, complemented with several examples and exercises. Finally, non-ideal and multiphase systems are presented, as well as specific topics of biomass thermal processes and heterogeneous reactor analyses. The work closes with a unique section on the application of theory in laboratory practice with kinetic and reactor experiments. 

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