Clinical laboratory automation labeling

A major advance in the automation of specimen identification in the clinical laboratory has been the incorporation of bar coding technology into analytical systems.In practice, a bar coded label (often generated by the laboratory information system and bearing the specimen accession number) is placed onto the specimen container and is subsequently read by one or more bar code readers that have been strategically placed at key positions in the analytical train. The resultant identifying and ancillary information is then transferred to and processed by the system software. 

After amplification, tlie products can be detected by various methods. Simple gel electrophoresis with ethidium bromide staining may suffice. When greater accuracy is required, one of the primers can be fluorescently labeled so that after PCR the fragments are accurately sized on a DNA sequencing device. Alternatively, some form of hybridization assay can be used to verify or analyze the amplified product. Automated methods are always attractive and closed-tube methods are particularly advantageous in the clinical laboratory. Adding a fluorescent dye or probe before amplification allows thermocyclers equipped with optical detection to analyze the reaction as it progresses (real-time PCR) or after the reaction is complete (endpoint measurement) without need to process the sample for a separate analysis step. 

Identification is a major problem in clinical laboratories, and serious untoward events can occur with misidentified specimens. Unambiguous identification is possible today with bar-coding and similar machine-labeling techniques (31). The model discussed here is for testing patient-derived materials in a clinical laboratory the model can, of course, be extended to other applications. A machine-readable label on every specimen is the contemporary standard of modern equipment. Keying in identifiers to an instrument is less desirable owing to the inevitable human errors. In our experience with bar-code readers, they read the label correctly or don t work at all. The topic, automated specimen identifications, is described in more detail in Section 8.2 here (32). 

Future trends in IA reside in several areas, including (a) new labels and improved sensitivity, (b) automation, (c) simultaneous multianalyte assays, and (d) genetic engineering. The trend must be to exploit the current advantages of IAs, which include sensitivity, simplicity, limited cost, and speed. Our goal must be to make the assays faster, better, and more accessible. However, it must be remembered that what is appropriate and acceptable in the clinical chemistry laboratory may not be acceptable or may be much less appropriate in the biopharmaceutical laboratory. Only trends that may apply to the pharmaceutical analyst will be discussed here. 

Radioisotopes have been widely used an indicators in assays that are appropriately referred to as radioimmunoassays (RIA). Yalow won the Nobel Prize for work leading to the development of RIA (15). RIA s typically have a high degree of sensitivity and reproducibility. Additionally, automated instruments have been designed that make it possible to process a large volume of samples. RIAs are also very popular in clinical microbiology laboratories. Drawbacks for RIA s include the need for expensive equipment to read the radioactive signal, short half life of some labels, potential health hazards to personnel, and waste disposal problems. 

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