LS Instruments

For aqueous samples, polystyrene particles are often the best choice. LS Instruments offers monodisperse spherical polystyrene particles specially designed for DWS applications. In particular, the batch does not contain surfactant traces (in contrary to most other suppliers) that could contaminate your sample.

• mean diameter: 460 nm, depending on the batch (hydrodynamic size, measured by DLS and SLS)
• PID: <0.11 (PID=‹d²›/‹d›²
• zeta potential: -80±10 mV (Smoluchowski approximation, in 10 mM phosphate buffer)
• specific gravity: 1.05
• solvent: distilled water
• Quantity: 10 mL with 8.3 wt.% particle concentration
• Price: 210 CHF (excl. shipping cost and taxes that may apply)

The particles are synthesized without surfactant to protect your sample against contamination. The production of the DWS tracer particles is outsourced, hence the average size and concentration may differ from batch to batch. Each batch is characterized separately.

Titanium dioxide particles have excellent optical properties and allow low doping of your sample for a given turbidity. For improved dispersibility, the TiO₂particles are coated with silica. The particles come in powder form and are thus easy to add. Due to the significant particle density, TiO₂ particles are most appropriate for samples with high viscosity or highly structured samples.

• Mean diameter: 360 nm
• Size standard deviation: 200 nm
• Specific gravity: 4.0
• Quantity: 2 g particles in powder form
• Price: 110 CHF (excl. shipping cost and taxes that may apply)