Deoxyribonuclease (DNase) is an enzyme that is ubiquitously present in the environment and many biological materials. The presence of DNase poses a threat to many molecular biology experiments, as DNAse can degrade DNA. Detection methods such as PCR rely on plastics, chemicals, and solutions that are free of DNase. Published methods for detecting DNase are often time-consuming, non-quantitative, and have low sensitivity. In contrast, the DNase Alert kit system is a rapid and convenient detection method that can detect DNase contamination in 10 minutes or less.
The DNase Alert kit system includes a unique substrate that is labeled with both a fluorescent reporter and a quencher. Due to the proximity of the fluor and quencher, the un-cleaved substrate emits very little fluorescence. When DNase is present, the bond between the fluor and quencher is severed, resulting in a bright green signal when excited at the appropriate wavelength. The degree of substrate cleavage is proportional to the level of DNase contamination and can be monitored by the increase in fluorescence on a fluorometer.
This kit can be used to detect DNase I and other DNA nucleases that cleave double-stranded DNA, as well as enzymes that cut single-stranded DNA, such as Exonuclease III, mung bean nuclease, micrococcal nuclease, Bal31 nuclease, S1 nuclease, T7 endonuclease, etc. Most reaction buffers and solutions used for DNA can be tested with this kit, but some systems are incompatible, such as (1) Gel Loading buffer and other dark solutions: Dark solutions may interfere with the excitation of fluorescence or block its emission, making them incompatible with the DNase Alert kit detection system; (2) Solutions that inhibit DNase activity: Since DNase must be active to be detected, solutions that inhibit DNase activity cannot yield reliable results in the DNase Alert kit detection system. Known common DNase inhibiting solutions include high ionic strength solutions (such as 5 M NaCl, 20 X SSC, 3 M sodium acetate, etc.), solutions with a pH less than 4 or greater than 9, dispersants, detergents, chelating agents, or any solution that denatures proteins (such as SDS, guanidine thiocyanate, urea, EDTA, etc.); (3) Solutions that cause chemical instability of the DNase Alert substrate: Solutions that chemically degrade the DNase Alert substrate are also not suitable for testing with the DNase Alert kit detection system, as they may produce false positive signals. The DNase Alert substrate is unstable in solutions such as those with a pH greater than 9 and corrosive solutions (strong acids, strong bases, bleach).
The kit (500 T) contains reagents sufficient for 5×96 high-throughput assays, allowing for sensitive detection of DNases in a simple and easy-to-use fluorescence assay, providing real-time results, and enabling the certification of plastics, enzymes, solutions, and other biological materials as free of DNase before DNase-sensitive applications such as PCR.