title: Gold-coated capillary based 2,4-dichlorophenoxyacetic acid chemi-luminescent assays: possibilities towards multianalysis.
abstract: The application of gold-coated glass capillaries for the design of a sensitive chemiluminescent immunoassay for 2,4-dichlorophenoxyacetic acid (2,4-D) is reported. The gold coating on the glass capillaries has been partially characterized and its effect on enhancing the signal intensity has been measured. A simple photo-multiplier tube-based photon detector is used for this purpose. At least three times improvement in the signal intensity is observed compared to uncoated glass capillaries, with a consequent improvement in the sensitivity of detection. Using such gold-coated glass capillaries, 2,4-D in the range 10(-9) to 10(-13) mol/l is detectable at a precision of +/-15% (CV%) and a limit of detection of 10(-15) mol/l is achievable. The possibility of using such gold-coated capillaries with a portable multianalytical set-up for field studies is also demonstrated.
authors.affiliation: Department of Pure and Applied Biochemistry, Box 124, Center for Chemistry and Chemical Engineering, Lund University, S-22100, Lund, Sweden.
authors.forename: Kumaran
authors.initials: K
authors.lastname: Ramanathan
authors.forename: Anatoli
authors.initials: A
authors.lastname: Dzgoev
authors.forename: Juraj
authors.initials: J
authors.lastname: Svitel
authors.forename: Birgitta
authors.initials: B
authors.lastname: Rees Jonsson
authors.forename: Bengt
authors.initials: B
authors.lastname: Danielsson
mesh_terms: D015084:2,4-Dichlorophenoxyacetic Acid / Q000032:analysis*; D004867:Equipment Design; D006046:Gold / Q000737:chemistry*; D006540:Herbicides / Q000032:analysis*; D007118:Immunoassay / Q000295:instrumentation* / Q000379:methods*; D008163:Luminescent Measurements; D012680:Sensitivity and Specificity
chemical_list: D006540:Herbicides; D015084:2,4-Dichlorophenoxyacetic Acid; D006046:Gold