Novel DNA Extraction and Preservation for Identification of Micro-organisms On-site using Novel Nucleic Acid Extraction Cards for the Oil and Gas Industry

摘要

Traditional microbiological methods based on culturing procedures such as the Most Probable Number (MPN) technique have been used for many years to monitor microbial numbers in oilfield samples. However, such methods are far from ideal as it is estimated that only 0.01-10% of all micro-organisms present in environmental samples are culturable by these methods. In addition, without further extensive procedures being carried out, such methods cannot identify the variety of micro-organisms in the sample. Molecular microbiological methods (MMM) negate such problems, providing information on the majority of micro-organisms present in an environmental sample. However, traditional MMM do have their drawbacks, particularly if employed on offshore oil installations. Such problems include microbial population changes occurring during transportation from the installation to the testing laboratory; additionally, the transportation and use of hazardous chemicals employed in traditional DNA extraction procedures limit the use of these methods on offshore installations. One new technology for the oil and gas industry, described as 'Nucleic Acid Extraction Card' (NAEC), offers a simple and convenient solution to sample transport and on-site DNA extraction problems. The cards are impregnated with chemicals that lyse the cells and preserve the extracted DNA, thus eliminating the need for hazardous DNA extraction/purification chemicals. Hence, the cards 'fix' the DNA onto the card so that the microbial population at the point of sampling is preserved, eradicating concerns of changes in microbial populations occurring during sample transport. The paper will discuss the mode of operation of the NAEC, trials with the cards on oilfield samples, comparisons with traditional DNA extraction procedures and recent developments with the technology. The paper will conclude with an example of how NAEC technology has been used to develop proactive solutions to microbiological problems in the oil & gas industry.