Cytiva's Whatman Polycap SPF (Serum Prefilter) Capsule Filters are optimized for prefiltration applications. They are typically used upstream of a Polycap AS or a Polycap TC capsule during enzyme and buffer filtration.

• Three layers of filter media: fine glass microfiber (GMF), ultrafine GMF, and polyethersulfone (PES)
• Suitable for hard-to-filter solutions, particularly sera and protein solutions
• Can be sterilized by autoclaving
• Well suited for serum, viral suspension, nutrient, biological, immunological, enzyme, and buffer filtration

Biological filtration, especially serum filtration, is often difficult because of the high concentration of complex particulates, lipids, triglycerides, and lipoproteins in solution that can clog filters. Single-layer membrane filters clog rapidly without proper prefiltration.

Polycap SPF prefilters are highly suitable for biological filtration, especially serum, buffer, and enzyme filtration, because of the density graded pre-filtration layers they contain. Prefiltration with Whatman Polycap SPF can help extend the life of the final filter.