Evosep Proteomics / Evotip Pure
Consumable
Evotip Pure™
A high-efficiency disposable trap column that combines desalting with LC-MS sample introduction. One step instead of three — which removes carryover, protects the analytical column, and lets a prepared sample wait 28 days for instrument time without degrading.
1 µg loading capacity
Single use, no carryover
28-day storage
Down to 250 pg
0.06%Carryover of total signal following 50 ng HeLa injections
28 daysStorage on the Evotip with no systematic loss
+20%Recovery from fewer sample transfer steps
~1.25Pipette tips consumed per sample in an automated workflow
250 pgSingle-cell-equivalent loads handled routinely
How it works
Desalting and sample introduction, collapsed into one step
In a conventional workflow, peptides are desalted, dried, resuspended and transferred to a vial before injection. Every one of those steps loses sample to plastic and adds a chance to go wrong.
Evotip Pure replaces them. Peptides are loaded directly onto the tip, where they are desalted and immobilised. The Evosep system then partially elutes them — taking the peptides you want to measure and leaving large, hydrophobic molecules behind on the tip, which is discarded. That single design decision is what produces the three things this page is about: no carryover, a long-lived analytical column, and a sample that can sit on the bench until the mass spectrometer is free.
Loading capacity is 1 µg. Because desalting is integrated with elution, less starting material is needed than in a traditional workflow where offline desalting and elution happen separately.
Evotip Pure integrates peptide purification with sample loading and elution. Source: AN-022D, Figure 1.
No carryover
Single-use trap columns mean the injection system carries nothing from one sample to the next.
Column longevity
Partial elution keeps large, hydrophobic molecules off the analytical column, so it lasts.
Fewer transfer steps
Less exposure of peptides to plastic surfaces, which directly improves recovery.
Decoupled scheduling
Prepare hundreds of samples now, analyse them when the instrument is free.
Carryover and robustness
Nothing survives from one injection to the next
Carryover is the failure mode that quietly ruins a large cohort: a trace of the previous sample turning up in the next one, most damaging exactly when the next sample is small. A disposable trap removes the mechanism.
- 0.06%Carryover of total signal after 50 ng HeLa injections, and 0.2% after 50 ng plasma — measured across 480 injections (AN-022D).
- 0.6%Carryover into a 250 pg single-cell-equivalent sample following 50 ng plasma; 0.02% following 50 ng HeLa (AN-032B).
- <1.7 sRetention time SD for five diagnostic peptides across 190 injections of 50 ng HeLa.
- <1% CVPressure profile across roughly 400 sample injections, with no systematic build-up — the analytical column stays protected.
Why the pressure trace matters
Backpressure creeping upward over a long run is how a column tells you it is collecting material it cannot release. Across close to 500 LC-MS experiments on the 200 SPD method, the pressure stayed consistent — evidence that partial elution is doing its job and large hydrophobic molecules are leaving with the tip rather than accumulating on the column.
At cohort scale. In a separate study of an automated plasma pipeline, carryover stayed below 0.2% across more than 1,100 patient plasma samples — 1,392 injections including controls — analysed in under seven days (AN-041A).
Sources: AN-022D and AN-032B in the literature room.
Sample storage
Preparation stops being tied to instrument availability
The scheduling constraint in most labs is not preparation capacity — it is mass spectrometer time. Loaded Evotips can wait, which lets you prepare in batches that suit the chemistry rather than the queue.
28 days
HeLa digest loaded at 5 ng and 50 ng was analysed immediately and up to 28 days later. Precursor identification rates varied slightly across the period, with no systematic losses over time (AN-022D).
Low input, 48–72 hours
At single-cell-equivalent loads of 250 pg, more than 90% of precursor identifications were preserved after 48 hours of on-tip storage, and close to 75% after 72 hours (AN-032B).
Nine days, automated
In an automated end-to-end workflow with samples stored in 0.1% formic acid at 4 °C, no significant sample loss was seen for up to nine days (AN-040A).
The comparison that makes the case. In a controlled test, a sample was held in a sample plate for a few seconds before Evotip loading — one extra transfer step. Even at a relatively generous 50 ng HeLa load, that step caused significant losses, most pronounced in the middle and hydrophobic part of the gradient where peptides stick to plastic. The tip is not just storage; it is one fewer surface.
Low input and single cell
Concentrating dilute samples instead of diluting them further
Most autosamplers rely on a sample loop, which sets a floor on how small a volume can be injected sensibly. Evotip Pure works the other way round: dilute samples are concentrated onto the tip as they load.
- 250 pgSingle-cell-equivalent HeLa digest loaded, analysed and stored routinely.
- <7%Median CVs for both 50 ng plasma and 50 ng HeLa in a mixed sequence designed to provoke carryover.
- 2 sAverage retention time SD across 340 runs at 250 pg on the Whisper Zoom 120 SPD method.
- DDMAdding n-dodecyl-β-D-maltoside increases precursor identifications and quantitative precision at low loads, without affecting storage.
Evotip Pure addresses the analytical challenges specific to high-sensitivity workflows — capture, recovery and storage of very small peptide amounts. Source: AN-032B, Figure 1.
End-to-end automation
Loading the tip inside the digestion workflow, not after it
Conventional liquid handling automates digestion well but stalls at post-digestion processing. Loading Evotips directly on the liquid handler closes that gap — digestion, clean-up and storage become one hands-free process.
What direct loading changes
In a controlled comparison, half the samples from a PAC digestion were loaded straight onto Evotips from the sample plate; the other half were dried in a vacuum centrifuge and resuspended in 0.1% formic acid first — the traditional route.
Directly loaded samples showed higher summed precursor intensities. The difference was most pronounced for hydrophobic peptides eluting late in the gradient, which is precisely where adsorption to plastic does its damage. Notably, direct loading at 10% of the digest outperformed reconstituted samples at 20%.
Supported liquid handlers
Automated Evotip loading protocols are published for the platforms most labs already own, each with its own application note in the literature room:
Opentrons OT-2 — up to 288 tips per run
Agilent AssayMAP Bravo — 96 tips in ~4 minutes
Beckman Coulter Biomek i5 / i7 — up to 576 samples per run
Evosep Lupo — Evokit workflows, up to 384 samples
Step-by-step protocols and scripts for each platform are published by Evosep at evosep.com/support/automation.
Specifications and ordering
Evotip Pure
Specifications
| Format | Single-use disposable trap column, supplied in boxes of 96 |
| Loading capacity | 1 µg |
| Function | Integrated desalting and LC-MS sample introduction, with partial elution |
| Storage window | Up to 28 days loaded, with no systematic loss |
| Recommended storage | Submerged in solvent A, or in 0.1% formic acid at 4 °C |
| Low-input range | Demonstrated down to 250 pg single-cell-equivalent loads |
| Compatibility | Evosep One and Evosep Eno; on-deck loading on OT-2, AssayMAP Bravo and Biomek i5/i7 |
Ordering information
| Part number | Pack size | Tips |
|---|---|---|
| EV2011 | 1 box | 96 tips |
| EV2013 | 10 boxes | 960 tips |
| EV2015 | 50 boxes | 4,800 tips |
| EV2018 | 100 boxes | 9,600 tips |
Evotips are included in Evokit sample preparation kits for Evosep Lupo. Contact us for pricing and availability.
Go deeper
The studies behind these numbers
Application note · AN-022D
Highly efficient disposable trap column with no carry-over
Carryover, quantitative reproducibility, retention time stability and 28-day storage recovery across 480 injections of HeLa and plasma digest.
Open in the literature room → Application note · AN-032BEvotip Pure is the key to accelerate scalable single-cell proteomics
Loading volume, DDM, carryover into single-cell-equivalent samples, and stability across 340 runs and three days of on-tip storage.
Open in the literature room → Application note · AN-040AEvotip Pure for end-to-end workflows
Direct loading versus dried and reconstituted samples, plus the tip, reagent and recovery consequences of removing transfer steps.
Open in the literature room →
Product page
Evosep Eno™ — LC separation platform
Where the Evotip goes next: ten standardized methods, performance data and technical specifications.
Explore Evosep Eno → Product pageEvosep Lupo™ — sample preparation system
Evokit workflows that end with a loaded, ready-to-analyse Evotip and a full traceability record.
Explore Evosep Lupo →Get started
Take the transfer steps out of your workflow
Talk to a specialist about how Evotip Pure fits your sample types, your liquid handler and your throughput.