Application of magnetic nanoparticles in full-automated chemiluminescent enzyme immunoassay

The magnetic nanoparticles (MNPs) Therma-Max (TM) were used as a carrier to develop an automated sandwich chemiluminescent enzyme immunoassay (CLEIA) to detect thyroid-stimulating hormone (TSH) in a sensitive and specific way. The Therma-Max (TM) particles allow for automation because, unlike magnetic microspheres, they are completely dispersed in aqueous solution and allow for accurate automatic handling. Signal intensities detected with MNPs were 8-fold higher than those found with conventional micron-sized magnetic particles. A reproducibility study suggests that these particles allow for a stable detection method, as the coefficient of variation(CV) is less than 6% (n = 10). (C) 2009 Elsevier B.V. All rights reserved.