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Nitrocellulose Membrane & Test Lines

What it is

The nitrocellulose membrane is where the test and control lines are immobilized — the readout zone of a lateral-flow test.

How it works

A capture antibody is dispensed at the test line and an anti-species (control) antibody at the control line. As the sample–conjugate complex flows past, it binds at the test line (proportional to analyte) and always binds at the control line (confirming the test ran correctly).

Why it matters

The control line validates each device, and test-line intensity reflects analyte level — understanding this is key to reading results and spotting invalid tests.

Key components

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Written by the Progene Bio Technical Team · Last reviewed: 2026-09-12