SpheroTechnical Notes #14 - Determining PMT Linearity in Flow Cytometers Using the SPHERO™ PMT Quality Control Excel Template

The fluorescence linearity of flow cytometers is affected by optical alignment, laser power, electronical offsets, and amplifier calibration1. In addition, it is important to monitor and validate flow cytometers’ performance due to the nature of the information obtained during diagnostic testing. As a result, it is recommended that the linearity of the flow cytometer is determined on a monthly basis, after instrument repair, and after instrument relocation(2).

The SPHERO™ Calibration Particles and SPHERO™ PMT Quality Control Excel Template (PMT QC Template) are designed for linearity calibration and long term performance tracking of flow cytometers. They will help flow cytometer users verify the operation of their instruments. The PMT QC Template is a valuable tool for determining the linearity of log amplifies. The information acquired from this template should be implemented into flow cytometer calibration documentation. The user can determine a schedule for routine maintenance procedures and tolerance limits of linearity based on instrument trends or malfunctions using this template.

The SPHEROTM Rainbow Calibration Particles (RCPs) and Ultra Rainbow Calibration Particles (URCPs) contain a mixture of similar size particles with different fluorescence intensities.
Select the link below to download the complete SpheroTECHNICAL NOTE. (PDF format)

SpheroTechnical Note #14 will provide the following information:
  • The use of the Rainbow Calibration Particles (RCPs) for the determination of the logarithmic amplifier linearity
  • The use of the PMT QC Template to determine the number of related fluorophores for an unknown sample or other particles
  • References using the RCPs for the stardarization of flow cytometers