Small-Volume Concentration of Viruses from Environmental Water Samples

Take virus-spiked tap water to model virus-contaminated environmental water.

Transfer it into a filter assembly containing an electropositive filter membrane.

During filtration, negatively charged viruses adsorb to the electropositive filter. Repeat the filtration step with the remaining tap water. Apply a vacuum to remove residual liquid.

Add the elution solution containing protein-rich beef extract. The negatively charged proteins compete for adsorption sites, displacing the adsorbed viruses into the solution.

Apply a vacuum to collect residual liquid.

Mix the filtrate with negatively charged adsorption particles for further virus concentration.

Add acid to introduce hydrogen ions that neutralize negative charges and reduce electrostatic repulsion, promoting viral adsorption onto the particles.

Filter to retain the virus–particle complexes on a pre-filter membrane. Apply a vacuum to remove excess liquid.

Add a small volume of alkaline elution buffer.

The introduced hydroxide ions restore negative charges and increase electrostatic repulsion, releasing the viruses into the solution.

Apply a vacuum to collect the concentrated virus.

Measure out 100 milliliters of the spiked tap water using a