title: Evaluation on the use of reactive dye-modified polylysine as the biomarker in immunochromatographic test application.
abstract: An improved dye immunochromatographic test (DICT) using polylysine (PL) as conjugate spacer loading dye molecules to enhance chromophor color intensity with the potential of a simultaneous multicolored assay has been developed. To construct this new effective chromophor, a dyeing process coupling a reactive dye, Procion Blue MX-7RX (PB7RX), with PL of different molecular weights was performed. The optimal conjugate condition between PB7RX and PL was studied. It showed that under the optimized dyeing conditions, a PL molecular weight of 189.4 kDa and a molar ratio (mol dye/mol amine group in PL) of 1.5 were obtained. The resulting dyed PL chromophor, used as both a spacer and a color intensifier, was further labeled to a model antibody, anti-human serum albumin (anti-HSA), to build a PB7RX-PL-anti-HSA (PPA) conjugate. The PPA obtained in this way generated the highest color intensity of 19,455 assayed by immunochromatographic test strip under densitometer scanning. A competitive DICT for determination of HSA was carried out. A linear range between 0 and 18.77 μg/ml with a detection limit of 0.49 μg/ml was observed. A test for using dyed PL chromophors as biomarkers was also performed to demonstrate the feasibility of a multianalyte immunoassay.
authors.affiliation: Department of Chemical Engineering, National Chung Hsing University, Taichung 402, Taiwan.
authors.forename: Wei-Feng
authors.initials: WF
authors.lastname: Chang
authors.forename: Shwu-Jinng
authors.initials: SJ
authors.lastname: Wang
authors.forename: Sin-Fang
authors.initials: SF
authors.lastname: Lai
authors.forename: Chwen-Jen
authors.initials: CJ
authors.lastname: Shieh
authors.forename: Kuang-Pin
authors.initials: KP
authors.lastname: Hsiung
authors.forename: Yung-Chuan
authors.initials: YC
authors.lastname: Liu
mesh_terms: D000906:Antibodies / Q000737:chemistry / Q000276:immunology; D015415:Biomarkers / Q000737:chemistry; D004396:Coloring Agents / Q000737:chemistry*; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D011107:Polylysine / Q000737:chemistry*; D012709:Serum Albumin / Q000032:analysis* / Q000276:immunology; D014227:Triazines / Q000737:chemistry*
chemical_list: D000906:Antibodies; D015415:Biomarkers; D004396:Coloring Agents; D012709:Serum Albumin; D014227:Triazines; C036598:procion blue MX-R; D011107:Polylysine