title: Aptamer biosensors for label-free colorimetric detection of human IgE based on polydiacetylene (PDA) supramolecules.
abstract: In this study, we demonstrate an aptamer-based biosensor (apta-biosensor) using PDA liposomes for label-free detection of allergy diagnosis by hIgE detection. In order to detect the target hIgE, the surface of PDA liposome were functionalized with hIgE antibody and anti-hIgE aptamer as a receptor, and the target hIgE onto the receptors was detected by the change of fluorescence signal. The hIgE antibody-modified PDA liposome biosensor had a serious problem that the immune reaction between receptor and target could not powerfully affect the change of florescence signal on PDA liposome. In order to solve this problem, the anti-hIgE aptamer which was far smaller than whole antibody was introduced as the receptor for the PDA liposome system. An aptamer-based PDA liposome biosensor was able to measure a quantity of target protein with various concentrations and at this time the detection limit was 141 ng/mL of the hIgE concentration. These results enabled diagnosis of allergy disease by an aptamer-based PDA liposome biosensor because real allergic patients showed high concentration of hIgE in serum (greater than 290 ng/mL). Therefore, we suggest that aptamer-modified PDA supramolecules as promising candidates for development of label-free colorimetric biosensors.
authors.affiliation: Department of Chemical Engineering, Sungkyunkwan University, Suwon 440-746, South Korea.
authors.forename: Jun Pyo
authors.initials: JP
authors.lastname: Kim
authors.forename: Cheol Hee
authors.initials: CH
authors.lastname: Park
authors.forename: Sang Jun
authors.initials: SJ
authors.lastname: Sim
mesh_terms: D052157:Aptamers, Nucleotide; D001483:Base Sequence; D015374:Biosensing Techniques; D003124:Colorimetry / Q000379:methods*; D017931:DNA Primers; D006801:Humans; D007073:Immunoglobulin E / Q000032:analysis*; D000078789:Polyacetylene Polymer; D011108:Polymers / Q000737:chemistry*; D053279:Polyynes / Q000737:chemistry*
chemical_list: D052157:Aptamers, Nucleotide; D017931:DNA Primers; D000078789:Polyacetylene Polymer; D011108:Polymers; D053279:Polyynes; C082361:polydiacetylene; D007073:Immunoglobulin E