SILWET L-7600 is a polyalkyleneoxide-modified polydimethylsiloxane silicone surfactant that combines the strong hydrophobicity of organosilicon with the hydrophilicity of polyethers. It achieves ultra-low surface tension (as low as 20–25 mN/m) in both aqueous and organic solvent systems. Its unique molecular structure provides exceptional wetting capabilities (even on superhydrophobic surfaces like PTFE), along with anticoagulant, anti-hemolytic, and anti-static properties, making it a key functional additive in the development of solid-phase whole blood diagnostic reagents.Mechanism of Action

•Superior Wetting Ability: The siloxane segments rapidly adsorb onto hydrophobic interfaces (e.g., PTFE, nitrocellulose membranes), reducing the contact angle and promoting uniform liquid spreading.

•Anti-Red Blood Cell Interference: Inhibits nonspecific binding between red blood cells in high hematocrit (HCT) samples and solid-phase carriers, eliminating detection bias (e.g., false positives in coagulation tests).

•Non-Hemolytic Property: Acts gently on red blood cell membranes, preventing hemolysis and the release of hemoglobin, which can interfere with optical detection (e.g., colorimetric or fluorescent methods).

•Enhanced Penetration and Leveling: Accelerates reagent diffusion in dense matrices (e.g., blood clots, viscous samples), improving reaction homogeneity.

•Anti-Static Property: Reduces aggregation of particles (e.g., latex microspheres) caused by electrostatic adsorption, ensuring signal stability.

Application Scenarios

•Direct Whole Blood Detection Reagents: Added to solid-phase reaction plates or test strips (0.05%-0.2%) to block red blood cell adhesion and improve detection accuracy (e.g., CRP, D-dimer tests).

•Microfluidic Chips: Pre-coated onto hydrophobic microchannels (e.g., PDMS, PTFE) to optimize whole blood/plasma separation efficiency and reduce cell clogging.

•Lateral Flow Immunoassay Strips: Incorporated into sample pad treatment solutions (0.1%-0.3%) to accelerate whole blood penetration and inhibit red blood cell retention on the conjugate pad.

•Cell Lysis Enhancer: Combined with detergents (e.g., Triton X-100) at 0.05%-0.1% to enhance gentle lysis of blood/tissue cells.

•Optical Detection Anti-Interference: Used in colorimetric/fluorescence detection systems (0.05%-0.15%) to reduce light signal scattering caused by blood cell fragments.

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