Adenosine triphosphate, or ATP, is an enzyme that is found in all living cells and the various test systems that have been developed to detect it have found widespread applications both in the field of medicine and the food industry in particular. The molecule plays a critical role in the transfer of energy within the cell and the intimate association of this molecule with the phenomenon of life means that it serves as a unique marker for the detection of living organism of all kinds. The means to detect and quantitate live cells has become a vital tool in such fields as infection control and the quality control of food and beverages. Although there are a number of alternative approaches still in the research stage, the most common technology that is currently applied to the detection of this enzyme makes use of a naturally-occurring chemical reaction known as Bioluminescence. ATP test systems make use of the fact that, when exposed, under suitable conditions, to the enzyme luciferase (the same enzyme responsible for the firefly’s brilliant display), any Adenosine triphosphate molecules that may be present will react by emitting energy in the form of light.

This alone provides an investigator or a quality control technician with qualitative proof that there are viable cells present in the sample of material under test. In practice, the total intensity of the light produced as a result of this reaction is proportional to the number of cells present. Consequently, it can also serve as a means to quantitate the concentration of organisms in a sample. With the aid of an instrument known as a luminometer, the intensity may be extrapolated, for instance, to provide a count of the total or specific viable bacteria in the material under investigation.

Prior to the introduction of these modern ATP test systems, it was always necessary to carry out microscopic examinations and to incubate samples in culture media overnight to eliminate the presence of live organisms. Additional plating, incubation and biochemical testing would also have been required to identify the contaminant and to approximate its concentration by means of a colony count. Although such procedures continue to remain an invaluable tool in pathology and public health labs, today, these convenient kits serve as a highly reliable indicator of both viability and concentration. While these kits all work faster than the conventional methods, some are actually able to produce results in a matter of seconds. The precise nature of the kits varies according to their designated purpose. While some are essentially generic, reacting to the presence of all viable cells indiscriminately, others incorporate specialised substrates are more specific in their action allowing individual species such as Listeria and E. Coli to be detected and quantified within the same day.

Despite their speedy performance, the sensitivity provided by ATP test systems is quite remarkable. The combination of meticulously prepared reagents and high quality instrumentation has made it possible to detect adenosine triphosphate under various conditions in concentrations as low as 1 x 10-18 moles. The applications for this technology appear endless. It is used as a means to detect surface contamination in areas where food is prepared, in laboratories to test the efficiency of bactericidal agents and numerous studies have validated these procedures as suitable for use in hospitals to determine the efficiency of hand-washing facilities and other aspects of sanitation. The inclusion of test organisms within contaminated loads to monitor sterilisation procedures no longer requires lengthy microbiological examination. These kits can establish viability or the lack of it in a fraction of the time allowing sterilised items to be recycled with less delay. At water purification plants too, ATP test systems can save many hours over the use of conventional testing procedures.

In South Africa, IEPSA is a leading supplier of a wide range of diagnostic reagents and equipment with both in-depth knowledge and lengthy experience of the many varied fields in which this invaluable technology is now being applied worldwide. Every product that you purchase from us will have been sourced from leading international sources and guaranteed to be of the finest quality. It will have been stored in accordance with the manufacturer’s specifications to ensure optimal performance. The IEPSA team is constantly updating its knowledge of products and their application and is happy to offer expert support to all of those who make use of our biomedical and other products including these versatile, sensitive and reliable ATP test systems.

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