Polymeric micelle-based bioassay with femtomolar sensitivity.
Target-specific polymeric micelles loaded with fluorescence dye molecules in their hydrophobic cores were made from block copolymer of poly(caprolactones)23-b-poly(ethylene oxide)45. It was found that the micelles are stable against pH changes from pH 2 to 12 and temperature variation up to 65 degrees C. The dye molecules can be released to the solution on exposing the micelles to organic solvents or ultrasound. A rapid and highly sensitive immunoassay based on the above micelles was developed, and the assay can detect specific target proteins in the femtomolar range from complex biological samples such as serum mimics and cell lysate. For example, less than 0.15 U/ml of ovarian cancer-specific antigen 125, equivalent to 7.5 x 10(-15)M, can be reliably detected in solution. We also demonstrated that the assay can detect a cell surface biomarker, stage-specific embryonic antigen 4, from a single human embryonic stem cell.
Mouffouk
Fouzi
F
Department of Obstetrics and Gynecology, Rush University Medical Center, Chicago, IL 60612, USA.
Chishti
Yasmin
Y
Jin
Qiaoling
Q
Rosa
Michelle E
ME
Rivera
Melixa
M
Dasa
Siva
S
Chen
Liaohai
L
D001681:Biological Assay / Q000379:methods; D018394:CA-125 Antigen / Q000032:analysis; D018929:Cell Culture Techniques; D002460:Cell Line; D053595:Embryonic Stem Cells / Q000166:cytology / Q000502:physiology; D005260:Female; D005456:Fluorescent Dyes; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008823:Micelles; D010051:Ovarian Neoplasms / Q000097:blood; D011092:Polyethylene Glycols; D012680:Sensitivity and Specificity
D018394:CA-125 Antigen; D005456:Fluorescent Dyes; D008823:Micelles; D011092:Polyethylene Glycols