Pipette Tip Selection Guide: How to Choose the Right Tips

Choosing the wrong pipette tips is one of the most common — and most overlooked — sources of pipetting error in the lab. The right tip affects volume accuracy, contamination risk, sample loss, and even ergonomic fatigue over a full day of pipetting. We've seen labs lose entire experiments to aerosol contamination simply because they grabbed unfiltered tips for an RNA workflow. This guide gives you the framework to pick the right tip for every application, every time.

Why Pipette Tip Selection Matters More Than Most Labs Realize

A pipette tip is not a commodity. It's the final interface between your instrument and your sample. Poor tip-to-pipette fit creates air gaps that directly compromise the calibrated seal — and that means inaccurate volumes even from a perfectly calibrated pipette.

ISO 8655 governs the performance of piston-operated pipettes, and it's worth noting: tip selection is explicitly part of that standard. If you're running a GMP lab or any regulated workflow, you can't treat tips as an afterthought.

Beyond accuracy, tips affect:

• Contamination control — aerosols, carryover, cross-contamination
• Sample loss — especially with viscous or low-volume samples
• Tip ejection force — repetitive strain injury risk over high-throughput days
• Cost — bulk tips cost a fraction of racked tips, but aren't right for every workflow

Filtered vs. Unfiltered Pipette Tips: The Baseline Decision

This is the first fork in the road. Get it right before worrying about anything else.

Filtered tips (also called aerosol barrier tips) contain a hydrophobic polyethylene filter that stops liquid and aerosol from entering the pipette shaft. They are non-negotiable for:

• PCR and qPCR workflows
• RNA work (RNase contamination is permanent)
• Any application where cross-contamination between samples is a risk
• Clinical diagnostics

Unfiltered tips are appropriate for:

• Routine liquid transfers with non-hazardous reagents
• Cell culture media additions
• Colorimetric assays where carryover is not a concern
• High-throughput applications where cost per tip matters

If your lab runs mixed workflows, default to filtered. The cost difference per tip is small relative to the cost of a ruined experiment.

Universal Fit vs. OEM Tips: What the Research Actually Shows

This is where labs lose money in two opposite directions — overpaying for OEM tips when universal tips work fine, or using poorly fitting universals that compromise accuracy.

OEM (Original Equipment Manufacturer) tips are designed and validated specifically for one pipette brand. If you're running calibrated instruments in a regulated environment or high-stakes quantitative work, OEM tips eliminate fit-related variables entirely.

Universal tips are engineered to fit multiple pipette brands. Quality varies significantly by manufacturer. We've seen customers switch to Globe Scientific PosiStop tips from knockoff universals and immediately tighten their CV% on serial dilutions.

Workflow	Fit Recommendation
GMP / FDA-regulated	OEM or validated universal
ISO-accredited testing	OEM or validated universal
PCR / genomics	Filtered universal (Globe Scientific) works well
Routine transfers, cell culture	Universal unfiltered, bulk bag
Teaching labs / education	Bulk universal, cost priority

The Globe Scientific PosiStop line is engineered with a positive stop feature that provides a tactile and audible confirmation of full tip seating — which eliminates inconsistent seating as a variable. As an authorized dealer for Globe Scientific, we work directly with their engineering teams and can help you spec the right product for your application. Reach out at support@labsupplies.com.

Browse our pipette tips collection to compare Globe Scientific options by volume, format, and filter type →

Low Retention Tips: When You Need Them and When You Don't

Low retention tips have a hydrophobic surface treatment that minimizes sample adhesion to the inner tip wall. They matter most when:

• You're pipetting viscous solutions (glycerol-based buffers, BSA, serum)
• You're working with very small volumes (≤10µL) where even 0.5µL of residue represents significant error
• You're handling expensive reagents — enzymes, antibodies, oligonucleotides
• You need to minimize dead volume

For aqueous buffers at volumes above 20µL, standard tips work fine. Low retention tips cost roughly 2–3× more than standard tips. Don't use them as a default — use them where they earn their price.

Volume Range: Matching Tips to Your Pipette

Every tip is rated for a maximum volume. Using a 200µL tip on a 1000µL pipette — even if it physically fits — creates inaccurate transfers and risks tip blowout during dispensing.

Pipette Volume Range	Recommended Tip Volume
0.1 – 2µL (specialty)	10µL tips
0.5 – 10µL	10µL tips
2 – 20µL	20µL or 10µL tips
20 – 200µL	200µL tips
100 – 1000µL	1000µL tips
1 – 5mL (repeat pipettors)	Combitip or serological

The Globe Scientific PosiStop 20µL tip (Cat #154005) is a strong choice for low-volume genomics work — graduated, DNase/RNase-free, human DNA-free, and pyrogen-free. It ships from our USA warehouse in bulk bags of 1,000, which significantly reduces per-tip cost without sacrificing quality.

Racked, Bulk Bag, or Reloaded: Choosing Your Format

Tip format is a workflow and ergonomics decision as much as a cost decision.

Racked tips come pre-arranged in a tray, ready to load into a multichannel pipette or simply to grab one at a time without touching adjacent tips. They cost more but reduce contamination risk from manual handling and are essential for 8- or 12-channel multichannel work.

Bulk bags are the cost-efficient format for single-channel work where you'll load your own racks or use a tip box. The Globe Scientific 20µL PosiStop tips come in a 1,000-tip bulk bag — ideal for labs doing high-volume transfers or looking to minimize consumable costs.

Reload inserts sit between racked and bulk: you buy a base rack once and purchase inexpensive refill inserts. Good for labs with high tip volume that want to reduce plastic waste.

If you're autoclaving tips for sterile work, confirm the tip is rated for autoclave cycles — most quality tips handle 121°C/15 psi/20 min, but confirm before you run your first cycle.

DNase-Free, RNase-Free, Pyrogen-Free: Decoding the Claims

These certifications matter for specific workflows — but not all of them matter for every application.

• DNase/RNase-free: Required for nucleic acid work. Cross-contamination from residual nucleases destroys RNA instantly and can produce false PCR results.
• Human DNA-free: Required for forensic applications and any diagnostic testing where human DNA contamination creates false positives.
• Pyrogen-free: Required for any work involving cell-based assays sensitive to endotoxins, or pharmaceutical manufacturing.
• PCR inhibitor-free: Required for PCR/qPCR. Residual mold-release chemicals from tip manufacturing can inhibit polymerase activity.

Unless you have a specific reason to downgrade, defaulting to tips certified for all 4 is low-risk insurance. Globe Scientific's PosiStop line carries all 4 certifications as standard.

For a broader overview of liquid handling best practices, see our liquid handling guide.

Frequently Asked Questions

Do I need different tips for each pipette brand?

Not necessarily. High-quality universal tips with tight manufacturing tolerances — like Globe Scientific PosiStop tips — perform accurately across most major pipette brands. For regulated workflows, validate your universal tip against your specific pipette model and document the result. OEM tips eliminate that validation step but cost more.

What is the difference between filtered and unfiltered pipette tips?

Filtered tips contain a hydrophobic barrier that prevents aerosol and liquid from entering the pipette body. Use them for PCR, RNA work, and any application requiring contamination control. Unfiltered tips are lower cost and appropriate for general liquid transfers where cross-contamination is not a risk.

Can I autoclave pipette tips?

Most quality polypropylene tips — including Globe Scientific PosiStop tips — are autoclavable at 121°C for standard sterilization cycles. Always confirm with the manufacturer's spec sheet. Tips that have been autoclaved should be allowed to cool completely before use to avoid thermal expansion affecting tip fit.

What does "low retention" mean on pipette tips?

Low retention tips have a treated inner surface that reduces sample adhesion. They reduce dead volume and improve accuracy with viscous liquids, protein solutions, and very small volumes (≤10µL). For standard aqueous reagents at volumes above 20µL, they provide minimal benefit over standard tips.

How do I know if a tip fits my pipette correctly?

A correctly seated tip requires a firm press-on (one motion, no twisting) and creates an audible or tactile seal. There should be no visible gap at the tip-to-cone junction. Tips that require excessive force to seat or eject indicate poor fit and should not be used for accurate pipetting. The Globe Scientific PosiStop design includes an engineered stop that confirms full seating every time.

---

Starting a new lab? Get 15% off everything for 12 months with our LaunchLab program →

Shop Pipette Tips at LabSupplies.com — authorized dealer pricing, Globe Scientific certified tips, ships from the USA. →

---

— By the LabSupplies.com Technical Team