สารมาตรฐานขนาดและจำนวนอนุภาค Particle Size Standards and Count Controls

Applied Microspheres special formulation ensures a long shelf life and allows for storage at room temperature. The products are presented in 20-mL dropper-tip bottles, manufactured in the EU. They are composed of polystyrene and entirely suitable for the desired application, due to its spectral properties (RI = 1,59 @ 589 nm) and low density (1,05 g/cm3 ). This leads to slow sedimentation during experiments. The concentration is 104107 particles/mL, as such adjusted for direct use or easy dilutions. As a main feature, the particle number concentration is controlled extensively, based on representative quality controls. This results in a benchmark count accuracy with an uncertainty of ±10% only.

The particle diameters are traceable to SI which includes NIST traceability. Calibration is achieved using electron or optical microscopy, electrical sensing zone, single particle optical sizing, laser diffraction and analytical differential centrifugation, using reference materials calibrated by ISO/IEC 17025 certified national institutes as well as NIST Standard Reference Materials (SRM).