1. Filter cartridge or straw nozzle

Non-blocking nozzles and blocking nozzles and filter element suction heads are designed for different conditions. The unblocking filter nozzle is designed for routine laboratory work, and if you are removing substances that could contaminate the pipette, such as bacteria, viruses, volatile, corrosive or sticky chemicals, then you need to consider using an unblocking nozzle to protect the pipette and sample.

2. Pipette with filter element suction/pipette with filter element selection

For many insensitive applications, you can use a filter/no barrier or a standard pipette head. Often LABS use these cues to load agarose gels, isolate plasmid DNA, and other similar applications. Easy-to-use filter cartridge suction heads are the backbone of any lab, and as an added bonus, are often a less expensive option.