Interference caused by endogenous components of the sample

Also natural existing proteins of the specimens can cause interference.
Well-known interfering substances in human sera are: albumins, complement, lysozyme and fibrinogen. Endogenous proteins can bind assay antibodies or target analyte and so mask them. Substances can be demasked by using LowCross-Buffer® as assay buffer.

cross-reactivity with capture and detection antibody
Cross-reactivity with capture and detection antibody. In practice it is an uncommon phenomenon, but possible with antibodies of low specificity. Such interference can be caused by antibodies which are targeted on conserved amino acid sequences of a protein. These conserved amino acid sequences can also be found in other (therefore interfering) proteins.
binding analyte specimen protein
Masking of the analyte by a specimen protein. The capture antibody can not bind the epitope. Binding of analyte is not possible or bad (in case of sterical hindrance). The results are false negative signals.
illustration endogenous components

Assay Defender® - Total HAMA and interference blocker

Assay Defender®  is a ready-to use assay diluent for reduction of interference caused by HAMA (human anti-mouse antibodies), rheumatoid factors, nonspecific binding, cross-reactivities and matrix effects.
Assay Defender® is particularly suitable for human or animal specimens…

Certification EN ISO 13485

Additionally to the EN ISO 9001 certification, CANDOR is now also certified according to EN ISO 13485.