A pipette is chosen by the range the work sits in, and the tip is chosen by the pipette and the liquid. Above a millilitre the instrument changes character: air displacement becomes harder to hold accurate, and the alternatives are a positive displacement instrument or a serological pipette with a controller.
p20 pipette tips and matching the cone
p20 pipette tips are small enough that the seal on the cone decides the volume delivered, so a tip that almost fits is the commonest hidden error at these volumes. Filtered tips are the default for anything amplified, and a low retention surface changes recovery measurably for detergent free solutions. Rack format matters only for convenience; the taper matters for accuracy.
wide orifice pipette tips and viscous or fragile samples
wide orifice pipette tips have the end cut back so a larger aperture reduces shear and allows a viscous sample or an organoid to pass without damage. The cost is slightly poorer precision, since the wider opening drips and wets differently. For cell suspensions and genomic DNA the trade is worth it, and the tip type belongs in the method rather than in a drawer.
A cell culture pipette and the sterility that defines it
A cell culture pipette is not a different instrument but a different consumable discipline: individually wrapped sterile serological pipettes, filtered tips, and a controller that does not aerosolise. Plugged serological pipettes protect the controller from aspirated medium. What is bought here is the certification and the wrapping rather than any optical or mechanical property.
disposable pipette tips against washing anything
disposable pipette tips are single use because cleaning a tip cannot be validated and carryover at microlitre scale is invisible, so the only real choices are bulk, racked or refill formats and whether they are sterile or filtered. Waste volume is the argument for refill inserts. Autoclaving unsterile racked tips in the laboratory is common practice and its records belong with the rest.
precision pipettes and what the word promises
precision pipettes in a catalogue means an instrument whose accuracy and precision are specified per volume and certified, which every reputable pipette is, so the useful comparison is the published table rather than the adjective. What separates instruments in practice is the consistency of the seal over thousands of cycles and whether a calibration service exists locally.
A p10 pipette and the smallest honest volumes
A p10 pipette covers roughly half a microlitre to ten, and at the bottom of that range the relative error is large enough that a dilution and a larger transfer is usually the better experiment. Evaporation from the tip becomes significant at these volumes too. Reverse pipetting improves consistency for volatile and viscous liquids at this scale.
A p200 pipette as the general workhorse
A p200 pipette covers twenty to two hundred microlitres, which is most reaction setup and plate work, and it is the instrument a laboratory owns most of. Because it is used constantly it drifts first, which is the argument for including it in every verification round rather than only in the annual calibration.
pipette tip manufacturers, and buying outside the instrument's brand
Third party pipette tip manufacturers supply tips for most instrument brands at lower cost, and the question is whether the taper, the length and the stiffness match well enough to hold the published accuracy, which is settled by a gravimetric check rather than by a compatibility chart. Filter quality and the absence of extractables are the other two things worth testing before a bulk order.
Questions people ask about large volume pipette
Why use a wide orifice tip?
To reduce shear on viscous or fragile samples. Precision is slightly worse, which is why the tip type belongs in the method.
Are third party tips safe to use?
Often yes, but check them gravimetrically on your own instrument rather than trusting a compatibility chart.
What is the smallest volume worth pipetting?
At the bottom of a P10's range the relative error is large. A dilution and a larger transfer is usually better.