sample. These are usually meant to measure one analyte at a time, but many samples
may be measured rapidly.
Batch Analyzer In batch analyzer, one batch of a specific test is performed at a time
automatically by the analyzer. In these instruments, reagent mixture is prepared and
fed automatically, and one reagent is stored in the machine for running a test.
Random Access Autoanalyzers In such analyzers, more than one reagent is stored
at a time. The samples are placed in the machine, and it can perform any number of
specific tests on each sample (Figs.4.1 and 4.2).
The steps followed for analysis of sample on the automated systems:1.Identification of sample: The tubes containing blood or otherfluid samples for
analysis are labelled at collection center. On reaching the lab, the description of
sample is recorded in computers, and then they are processed.
2.Bar coding: The technology of bar coding is used by many clinical laboratories
for the identification of sample. Several analytical systems are equipped with bar
coding facility. A bar reader present in such systems reads and records the sample
information which is transferred to the system and processed by software.
3.Preparation and transport of sample: The sample is prepared before the analysis
is performed. Various steps like blood clotting, centrifugation of sample, and
Fig. 4.1Semi-autoanalyzers
14 4 Automation in Clinical Laboratory