Custom NULISAqPCR assay development

If no panel covers your protein, we can build the assay. We conjugate your antibody pair (or help you find one) to NULISA DNA barcodes, qualify the assay, and run your samples on the ARGO HT at fg/mL sensitivity. Up to four targets can go into one assay.

Trained by Alamar, Sept 2025 fg/mL sensitivity Up to 4 targets per assay Your antibodies or ours Small sample input

Why build a custom assay

The proteins panels leave out

Every fixed panel is somebody else's list. A custom NULISAqPCR assay gives you NULISA sensitivity on the protein you actually need, whether that's a novel target, a therapeutic, or a marker from a species nobody has made a panel for.

Sensitivity in the fg/mL range

The same two-antibody, DNA-barcoded chemistry as the NULISAseq panels, with a qPCR readout. Targets that sit below the floor of an ELISA become measurable in plasma, serum or CSF.

Small sample input

Input is measured in microliters. That matters for pediatric samples, CSF, rodent bleeds and biobank aliquots that can't be spent on a titration series.

Up to four targets together

Several antibody pairs can be conjugated and read in the same reaction, so a small custom panel is possible without running each protein separately.

We've done the training

Our team completed Alamar's NULISAqPCR custom assay development program in September 2025. We follow their conjugation and qualification workflow and know where the pitfalls are.

How it works

Your antibodies, NULISA chemistry

NULISAqPCR takes a matched pair of antibodies against your protein and attaches a short DNA oligo to each. When both antibodies bind the same molecule, the oligos are joined and the product is counted by qPCR. Two capture-and-release steps remove the sample background before amplification, which is where the sensitivity comes from.

You can supply your own validated antibody pair, or we can help identify candidates from commercial suppliers. We'll tell you early if a pair isn't likely to work, rather than after the conjugation.

About 100 µg of antibody per target for conjugation and qualification

Antibody pairs from you, or sourced with our help

Qualification report covering sensitivity, dynamic range, linearity and reproducibility

Samples run on the ARGO HT; data delivered normalized and QC-checked

Works in plasma, serum, CSF, tissue lysate, cell culture supernatant and aqueous humor

Discuss a target

Where it gets used

Following up a discovery hitYour Olink or NULISAseq run pointed at a protein that no targeted panel covers. We build the assay to confirm it in more samples.

Drug levels and PD markersQuantify a therapeutic antibody or a pharmacodynamic marker in clinical samples at concentrations a ligand-binding assay can't reach.

CNS and other scarce targetsLow-abundance neurological proteins in CSF or blood, where both the concentration and the sample volume are small.

Animal modelsMouse or rat targets that don't appear on any commercial panel, built once and reused across studies.

Assays headed toward diagnosticsEarly development work for companion diagnostic or IVD programs that need a quantitative, reproducible readout.

The process

From antibody to data in six steps

This is Alamar's NULISAqPCR workflow as we run it. Most of the calendar time is in the first three steps.

Step 1

Curate

Pick the antibody pair. You may already have one that works in a sandwich format; if not, we go through commercial options with you and flag pairs that are unlikely to perform.

Step 2

Conjugate

Each antibody is conjugated to its barcoded oligonucleotide using Alamar's chemistry. About 100 µg of antibody is needed per target.

Step 3

Qualify

The conjugated pair is tested for sensitivity, dynamic range, linearity and reproducibility. You get the qualification data before any study samples are touched.

Step 4

Load

Study samples are plated alongside calibrators and controls. Sample preparation is minimal.

Step 5

Run

The ARGO HT runs the immunoassay and the capture-and-release steps automatically; the qPCR readout follows.

Step 6

Analyze

Results are normalized and QC-checked, then delivered with the QC metrics so you can see how the numbers were derived.

Who asks for this

Typical requests

Academic groups

Working on a novel target, a rare disease or a newly described marker that no commercial panel includes, and wanting NULISA sensitivity on it.

Pharma and biotech

Programs that need to quantify a biologic, a PD marker or a safety marker at very low concentrations in trial samples.

Biomarker teams

Groups moving from a discovery dataset to a focused, quantitative assay they can run across a cohort, often bridging from Olink or NULISAseq results.

Preclinical scientists

Mouse or rat studies where the target of interest has no validated panel, and the same assay will be needed again next study.

Custom assay or an existing panel?

A custom assay takes longer and costs more up front than running a panel that already exists. It's worth it when the target isn't on any panel, or when you need a quantitative assay you'll run repeatedly. Here's how we think about it; if you're unsure, ask and we'll give you a straight answer.

Use an existing panel when

Your targets are already on a NULISAseq or Olink panel, you want broad coverage for discovery, or the study timeline doesn't leave room for assay development.

Build a custom assay when

The protein isn't on any commercial panel, you need fg/mL sensitivity on a specific target, you already have a validated antibody pair, or the assay will feed a diagnostic program.