John M. S. Bartlett.pdf - Bio-Nica.info

16 McDonagh
Fig. 1. Unidirectional flow in a PCR laboratory.
blocks, often with a heated lid, and a basic repertoire of cycling capabilities. If high
throughput using many different protocols is required in a diagnostic setting, then a
multiblock system with the advantage of adding satellite units may be appropriate.
More specialized machines with gradient blocks suitable for rapid optimization studies
or with specialized blocks for in situ PCR are also available.
Advances in technology have resulted in the development of real-time PCR systems,
which allow rapid cycling (50 cycles in less than 30 min). These systems are expensive
but provide benefits, including rapid throughput, efficient optimization, and further
reducing the risk of contamination with reactions and product analysis occurring in
a single tube.
2.2. Additional Equipment
Dedicated equipment for each area of the laboratory can be purchased from regular
laboratory suppliers. Contamination can often arise from breaks and spills in equipment,
such as centrifuges and waterbaths (4); therefore, important considerations include
the purchase of equipment that can be easily taken apart for decontamination (see
Note 1).
All areas require dedicated pipets (1). Plugged tips used with traditional pipets are
generally cheaper and easier to use than positive displacement pipets (see Note 2).
Storage space at 4°C and –20°C should be available in each area, along with access
to –70°C freezer facilities.
Laminar hoods are not always recommended, except at the sample extraction stage,
where they are required to protect the worker. Using individual workstations with