What Is RNA Capture and When Do You Need It

Team Dynamic Matrices | 25 March 2026

RNA capture refers to selectively isolating target RNA molecules from a complex biological sample, distinct from general RNA extraction, which pulls out all RNA indiscriminately regardless of identity. You need RNA capture specifically when your downstream application depends on enrichment of a particular RNA species, not just extraction of total RNA.

Common scenarios that call for capture

• Depleting unwanted RNA species, such as rRNA, before sequencing, to avoid wasting sequencing depth on material you don't need.
• Enriching low-abundance transcripts that would otherwise be drowned out by far more abundant RNA species in a standard library.
• Isolating viral RNA directly from clinical samples for diagnostic purposes, where speed and specificity both matter.
• Pulling down specific RNA targets for interaction studies with proteins or other RNA molecules.

Matching the method to the application

The right capture method depends on your target's abundance and how much off-target tolerance your downstream assay can handle. High-sensitivity diagnostic applications need capture chemistry with minimal off-target binding, since false signal directly affects clinical interpretation and patient outcomes. Sequencing applications care more about overall depletion completeness than absolute specificity for any single molecule, since the goal there is maximizing usable read depth across the whole library.

Matching these scenarios to riboLASSO and LASSOflex

The two scenarios above split cleanly along product lines. Depleting unwanted rRNA before sequencing is exactly what riboLASSO is built for: a ready-to-run rRNA depletion kit that removes ribosomal RNA from total RNA without beads or enzymes, so it doesn't eat into your sequencing depth. Enriching low-abundance transcripts, isolating viral RNA from clinical samples, or pulling down a specific DNA or RNA target for interaction studies are jobs for LASSOflex, where you swap in a custom catcher strand to capture whatever target you're after. Need a protein or antibody target instead? Contact us. If you're not sure which applies, the deciding question is simple: are you trying to remove something you don't want (riboLASSO), or isolate something you do want (LASSOflex)?

A simple way to decide if you need capture at all

If your downstream analysis would work just as well with total RNA, you likely don't need a dedicated capture step, and adding one only introduces extra processing time and potential sample loss. Capture becomes necessary specifically when the abundance or composition of non-target RNA would otherwise overwhelm your signal of interest.