Go with the flow: quick tip tips
OK, maybe it’s not the same as picking your “furever” friend…but to make sure that everything runs smoothly, it’s important to put just as much thought into reaching for a pipette tip as you do looking for your furred soulmate.Casting your mind back to those first bewildering days at the bench, you may remember the array of pipettes and liquid transfer tools pointed out to you by a helpful supervisor. There were pipettes for microliters, pipettes for bulk volumes, stepper pipettes that let you dispense seemingly endless 2 mL volumes into a never-ending rack of tubes… but each pipette and each tip was specific to the job, chosen expressly to ensure accuracy and consistency across experimental workflows.
Picking a pipette tip, it turns out, is much like picking a puppy: you want to choose the right one so it doesn’t leak everywhere or spread contamination and is well behaved around the lab (that’s lab as in laboratory).
Dogs come in all sizes and different shapes. There are dogs that love exercise, dogs that are good with kids, and dogs that just love to lie around all day. Whatever your lifestyle or apartment style, there’s a dog that fits the bill. And so it is with pipettes. Not only are there two types of pipette (air-displacement for aqueous solutions; positive displacement for viscous or volatile liquids), but each can be further customized for the job through choice of tip. Instead of activity level, furriness and apartment size, your choice depends on what sample you’re picking up and how you’re dispensing it.
Choose the correct tip for ideal sample recovery
Standard Tips: These are the general-purpose, multi-use lab pipette tips that are suitable for the bulk of pipetting needs, handling a wide variety of samples with ease and precision. Like Labrador Retrievers, they can cope with just about any situation without fuss.
Sterile with filter: These tips come with a guard filter between pipette and sample to stop cross-contamination. If you’re doing forensics, genomics, PCR or radioisotope work, you’ll want one of these guard dogs on duty to stop intruders.
Extended length: Sometimes more reach is better to tackle samples in hard-to-reach places. Shepherds use Border Collies to round up sheep; you can use an extended-length pipette tip to recover samples from long or narrow vessels, or to deliver them precisely into the depths of an agarose gel.
Low retention: Apparently, Afghan Hounds retain very little —annoying for training and discipline, but low retention is a boon for pipetting precious samples. Polymer technology makes sure that pipette tips are hydrophobic to minimize adhesion. Conserve samples by choosing coated pipette tips that minimize cling.
Specialty tips – designed for unique applications
Wide-orifice tips: If you work with genomic material or want to transfer hybridomas and other delicate cells without damage, then you’ll appreciate wide-orifice pipette tips in the same way that hunters favor the soft-mouthed Golden Retriever. At 70% wider than standard (that’s pipette tip, not the dog), wide-orifice tips excel in delicate situations such as transferring fragile cells and pipetting genomic macromolecules. They are also great for viscous samples.—like what?
Gel loading: If you’re handling electrophoresis gels, agarose or acrylamide, a gel-loading pipette tip helps you reach further with precision and speed. Shaped like the long, slender muzzle of a Saluki, these tips gently ‘nose’ small-volume samples right to where they’re needed at the bottom of the well.
Solvent-safe, carbon filtered: Combinatorial chemists should pay attention to the mastiff of the pipette-tip world. Not only resistant to many chemicals, these tips protect pipettes from attack by strong acids, alkalis and aggressive organic solvents to prevent tool failure. Stay safe!
Individually wrapped? These single-serve options for extra-sensitive applications are ideal for fastidious sterility in sensitive situations…or maybe you’re looking for a cat?
Along with tip choices, choosing the right kind of pipette tool can speed up your workflow. Multi-channel and electronic pipettes customizable to a range of plate sizes help with repetitive lab tasks like microplate filling. As well as ensuring consistency and accuracy, options like clip tips help with ergonomics, too. Their design interlocks with the barrel to reduce operator fatigue by reducing hand pressure required to load and unload the pipette with tips.
Efficiency and ergonomics means more walks in the park with your dog. Choose your pipette tips wisely.
Further Reading – Liquid Transfer
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