# Conjugate Pad Treatment Buffer Optimization for Whole Blood POCT Assays
## Abstract
**POCT manufacturers** developing **lateral flow strips** for whole blood samples must optimize conjugate pad treatment to prevent matrix interference. This note details buffer formulation strategies for **IVD Reagents OEM/ODM** projects.
## Introduction
Whole blood contains cells, proteins, and lipids that can interfere with lateral flow assay performance. Proper conjugate pad treatment buffer formulation is critical for hemolysis prevention, red blood cell filtration, and target analyte release.
## Materials Required
– Buffer salts (Tris, Borate, PBS)
– Surfactants (Tween-20, Triton X-100, Brij-35)
– Blocking agents (BSA, Casein, PVP)
– pH meter and conductivity meter
## Step-by-Step Protocol
1. **Base Buffer Selection**: Choose 10-50 mM Tris or Borate buffer (pH 8.0-8.5) for optimal antibody stability.
2. **Surfactant Addition**: Add 0.05-0.5% Tween-20 to reduce non-specific binding; test 0.1%, 0.25%, 0.5% concentrations.
3. **Protein Blocking**: Include 1-5% BSA or 0.5-2% Casein to prevent matrix protein adsorption.
4. **Hemolysis Prevention**: Add 0.1-1% chelating agent (EDTA) to minimize red blood cell lysis.
5. **Validation**: Test treated pads with 10 whole blood samples; evaluate background and test line clarity.
## Troubleshooting
**Q: High background with whole blood samples?**
A: Increase surfactant concentration (0.25% → 0.5% Tween-20). Add 0.5% PVP for additional blocking.
**Q: Weak test line intensity?**
A: Reduce protein blocker concentration; verify conjugate activity after buffer treatment.
## Conclusion & OEM/ODM CTA
Conjugate pad optimization enables robust whole blood **lateral flow strips** performance. Due Bio, established in 1987, offers comprehensive **IVD Reagents OEM/ODM** development. Contact: medtiger@foxmail.com