Purpose: To investigate the potential of zeolite granules in large-scale concentration of hepatitis A virus from seawater.
Methods: Hepatitis A virus strain HM175/18f was inoculated into 500 ml of artificial seawater and filtered through 2 g of zeolite granules contained in a layer of cheesecloth. The zeolite granules were immediately dried and incubated with 1 ml of eluent for 0.5 h at 42°C to elute the virus. RNA was extracted from 140 µl of the pre-filtered and post-filtered water and the eluate. qRT- PCR was conducted to determine the recovery rate.
Results: Zeolite granules (2g) were able to remove 99.9% of the viruses (5-6 logs) from 50 ml seawater , and 90%~96% of the viruses (7-8 logs) from 500 ml seawater. A variety of eluents were tested for their abilities to elute the virus. Results showed that sodium chloride (0.6M-5.8M, pH 2.6-10.6); calcium chloride (0.1%, 2%, 10%); EDTA disodium (0.1%, 0.4%, 1%, 10%); 0.1M glycine (pH 2 and 9); 0.5M phosphate buffer (pH 1-13); protein denaturants of various types (pepsin, trypsin, proteinase K, urea, and guanidine thiocyanate); ammonium salts (ammonium sulfate, ammonium acetate, ammonium phosphate); surfactants Triton X-100 and Tween-80 all failed in eluting the virus. However, sodium dodecyl sulfate proved to be rather successful; 1 ml of 5% SDS in 0.5M phosphate buffer (pH 12) could elute 5 logs of viruses from zeolite.
Significance: Zeolite can absorb up to 8 logs of hepatitis A virus from 500 ml of seawater in less than 1 minute and has the potential to be developed into a rapid concentration and detection method for hepatitis A virus in seawater.