Surfactant Free particles are specially made for applications that cannot tolerate the presence of surfactant. Our surfactant free particles are sold as both unmodified and carboxylated. The products listed below with a diameter larger than 0.7µm are essentially surfactant-free. For particles smaller than 0.7µm, a small percentage of surfactant is present (<0.05%). For these particles, the smaller the diameter, the higher the percentage of surfactant.Product specifications:Concentration: aqueous suspension of 10% w/vaverage diameter tolerance will be within 10% of each specified catalog numberavailable for order in 5mL, 15mL, and 100mL quantities