Influence of the physical and chemical properties of magnetic nanoparticles on their performance in a chemiluminescence immunoassay

• We studied the influence of magnetic particle properties on performance of CLIA.
• Magnetic particle with size of 1μm was a good carrier for CLIA.
• The established CLIA system for myoglobin could meet the needs of clinical detection.

ObjectivesMagnetic nanoparticles (MNPs) are important carriers in immunoassays. In this study, we investigated the influence of the physical and chemical properties of MNPs on their performance in a detection process.Design and methodsA comparative study of the properties of two MNPs with sizes of 200 nm and 1 μm (MNP-200 nm and MNP-1 μm, respectively) was conducted using the following four aspects: nonspecific adsorption to proteins (IgG was used as a model protein), influence of magnetic nanoparticles on the chemiluminescence signal, response speed to an external magnetic field, and intensity of the detection signal.ResultsMNP-1 μm exhibited lower nonspecific adsorption to IgG in serum, a weaker interference with the chemiluminescence signal, and a higher response speed to the external magnetic field than the same amount of MNP-200 nm. An automated chemiluminescence immunoassay system based on MNP-1 μm was also established.ConclusionsMNP-1 μm acts as an excellent carrier in an automated chemiluminescence immunoassay system for the analysis of serum samples from clinical patients.