Abstract
The effects of heat, sodium hypochlorite, diethyl ether, and ethyl alcohol on the activity of DNA polymerase (DNAβP) associated with hepatitis B virsus (HBV) in serum were evaluated. The response of DNAβP to heating at 60Β°C for 15, 30, 45, 60, 90, 120, 180, and 240 minutes was studied and the data suggested that there may be two types of DNAβP. The majority of DNAβP was type βaβ, and it showed a one log redution (D60) at 60Β°C in 36 minutes, while the remaining activity was type βbβ that showed a one log reduction (D60) in 340 minutes. Treatment of DNAβP with sodium hypochlorite at concentrations of 250 and 500 parts per million (ppm) of available chlorine resulted in a 20 to 25% reduction in DNAβP activity within one minute. Complete loss in detectable DNAβP activity occurred within one minute when available Clβ was 2500 ppm or greater. Various concentrations of ethyl alcohol (ranging from 10 to 70%) caused gradually increasing inactivation of DNAβP activity in ten minutes at 4Β°C. Ninety percent inactivation occurred with 60% alcohol. Overnight treatment of DNAβPβreactive material with diethyl ether at 4Β°C led to loss of detectable activity. A reduction in the titer of HBsAg was found following treatment with alcohol or ether. The possible use of DNAβP assay as an indicator of the rate of inactivation of HBV is proposed.