biostudies-literatureYoshikawa HNakatani Foundation for Advancement of Measuring Technologies in Biomedical EngineeringJapan Society for the Promotion of Science14510-14514https://www.ebi.ac.uk/biostudies/studies/S-EPMC9082109biostudies-literatureUnknown8(26)We evaluated optical pickup ELISA with an original microfluidic disk that contains eight radially arranged channels, which enable semi-automatic sample loading and washing. This disk-shaped chip composed of acrylic plates was fabricated by CO₂ laser machining and capture antibodies were immobilized in the channels. After the immunoreaction with antigens and enzyme-linked secondary antibodies, an enzyme-catalyzed nanoaggregation of <i>o</i>-phenylenediamine was detected by measuring the reflectivity change of a laser beam focused in the channel. The assay of C-reactive protein (CRP) was successfully performed in a short amount of time (approximately 20 min from CRP loading). The limit of detection was determined to be 2 ng mL^-1, which is more sensitive as compared withRSC advancesAn optical pickup enzyme-linked immunosorbent assay (ELISA) with a microfluidic disk.PMC908210915H05769Yoshikawa HYoshinaga MTamiya EfalseAn optical pickup enzyme-linked immunosorbent assay (ELISA) with a microfluidic disk.We evaluated optical pickup ELISA with an original microfluidic disk that contains eight radially arranged channels, which enable semi-automatic sample loading and washing. This disk-shaped chip composed of acrylic plates was fabricated by CO₂ laser machining and capture antibodies were immobilized in the channels. After the immunoreaction with antigens and enzyme-linked secondary antibodies, an enzyme-catalyzed nanoaggregation of <i>o</i>-phenylenediamine was detected by measuring the reflectivity change of a laser beam focused in the channel. The assay of C-reactive protein (CRP) was successfully performed in a short amount of time (approximately 20 min from CRP loading). The limit of detection was determined to be 2 ng mL^-1, which is more sensitive as compared with2018-01-01T00:00:00Z2018 Apr2025-04-05T13:24:08.55Z2025-04-05T13:24:08.55ZS-EPMC90821093554076410.1039/c8ra01149d