Comparison Of Dna Extraction Methods

Purified bacterial DNA is required for many procedures in modern molecular biology, but clinical microbiology now routinely utilizes DNA for the laboratory confirmation of various infections.[4,8,12] The infections requiring a laboratory diagnosis are primarily of bacterial, viral, or parasite etiology. As such, infections of public health importance are now often diagnosed by PCR, and even typing information is provided on the organism causing infection. One such example is meningococcal disease. For this infection, rapid, sensitive, and specific methods are required so that case contacts can be managed appropriately. Bacterial DNA can be amplified from clinical samples by PCR to characterize the infecting bacteri-um.[13-17] As well as dedicated DNA extraction robot systems, a number of commercially available DNA extraction kits can be automated[4,18] and can be modified appropriately to various platforms. Overall efficiency of such methods can be determined by throughput time, DNA yield, and labor intensity.[4] All three main methods of DNA extraction can be automated, but their overall efficiency differs according to manufacturer. Some commercial kits, such as the 96-well plate format of the Promega SV96 kit, allow easy adaptation for use on a liquid handling robot. A large number of samples can then be processed with little or no manual intervention. Such kits are extremely simple to use and can extract up to 96 samples in under 20 min. The kits based on the use of metallic beads are also very simple to automate. Some magnetic bead kits are very efficient and can rapidly extract high-quality DNA from a large number of samples automatically. Some kits produce more DNA per reaction than others although these may not necessarily be the best for automation and test specificity. Overall, it is difficult to compare methods and decide on the best because it depends on the sample type, downstream method required, and the assay type being performed. However, kits have been compared and automated for the extraction of bacterial genomic DNA from whole blood samples and the sensitivity, specificity, and efficiency of the kits compared. In that study, the Bilatest Beads DNA 2 kit and the Promega Wizard SV96 kit were the most successful kits in all areas[4] and have subsequently been used successfully for the laboratory confirmation of septicemia and meningitis caused by Neisseria meningitidis, Streptococcus pneumoniae, and Heamophilus influenzae.[18] Ultimately, the choice of kit depends on the needs of users, often whether they prefer a 96-well plate format or a metallic bead system.

Getting Started With Dumbbells

Getting Started With Dumbbells

The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.

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