title: Competitive inhibition assay for the detection of progesterone in dairy milk using a fiber optic SPR biosensor.
abstract: Analytical methods that are often used for the quantification of progesterone in bovine milk include immunoassays and chromatographic techniques. Depending on the selected method, the main disadvantages are the cost, time-to-result, labor intensity and usability as an automated at-line device. This paper reports for the first time on a robust and practical method to quantify small molecules, such as progesterone, in complex biological samples using an automated fiber optic surface plasmon resonance (FO-SPR) biosensor. A FO-SPR competitive inhibition assay was developed to determine biologically relevant concentrations of progesterone in bovine milk (1-10 ng/mL), after optimizing the immobilization of progesterone-bovine serum albumin (P4-BSA) conjugate, the specific detection with anti-progesterone antibody and the signal amplification with goat anti-mouse gold nanoparticles (GAM-Au NPs). The progesterone was detected in a bovine milk sample with minimal sample preparation, namely ½ dilution of the sample. Furthermore, the developed bioassay was benchmarked against a commercially available ELISA, showing excellent agreement (R2= 0.95). Therefore, it is concluded that the automated FO-SPR platform can combine the advantages of the different existing methods for quantification of progesterone: sensitivity, accuracy, cost, time-to-result and ease-of-use.
authors.affiliation: BIOSYST-MeBioS, KU Leuven, Willem de Croylaan 42, B-3001, Leuven, Belgium.
authors.forename: D
authors.initials: D
authors.lastname: Daems
authors.affiliation: BIOSYST-MeBioS, KU Leuven, Willem de Croylaan 42, B-3001, Leuven, Belgium.
authors.forename: J
authors.initials: J
authors.lastname: Lu
authors.affiliation: FOx Diagnostics BVBA, Temse, Belgium.
authors.forename: F
authors.initials: F
authors.lastname: Delport
authors.affiliation: BIOSYST-MeBioS, KU Leuven, Willem de Croylaan 42, B-3001, Leuven, Belgium.
authors.forename: N
authors.initials: N
authors.lastname: Mariën
authors.affiliation: BIOSYST-MeBioS, KU Leuven, Willem de Croylaan 42, B-3001, Leuven, Belgium.
authors.forename: L
authors.initials: L
authors.lastname: Orbie
authors.affiliation: BIOSYST-MeBioS, KU Leuven, Kasteelpark Arenberg 30, B-3001, Leuven, Belgium; Department of Microbial and Molecular Systems - Cluster for Bioengineering Technology, Campus Geel, KU Leuven, Kleinhoefstraat 4, B-2440, Geel, Belgium.
authors.forename: B
authors.initials: B
authors.lastname: Aernouts
authors.affiliation: BIOSYST-MeBioS, KU Leuven, Kasteelpark Arenberg 30, B-3001, Leuven, Belgium.
authors.forename: I
authors.initials: I
authors.lastname: Adriaens
authors.affiliation: BIOSYST-MeBioS, KU Leuven, Kasteelpark Arenberg 30, B-3001, Leuven, Belgium.
authors.forename: T
authors.initials: T
authors.lastname: Huybrechts
authors.affiliation: BIOSYST-MeBioS, KU Leuven, Kasteelpark Arenberg 30, B-3001, Leuven, Belgium.
authors.forename: W
authors.initials: W
authors.lastname: Saeys
authors.affiliation: FOx Diagnostics BVBA, Temse, Belgium.
authors.forename: D
authors.initials: D
authors.lastname: Spasic
authors.affiliation: BIOSYST-MeBioS, KU Leuven, Willem de Croylaan 42, B-3001, Leuven, Belgium. Electronic address: jeroen.lammertyn@kuleuven.be.
authors.forename: J
authors.initials: J
authors.lastname: Lammertyn
mesh_terms: D000818:Animals; D015374:Biosensing Techniques; D002417:Cattle; D006046:Gold; D053768:Metal Nanoparticles; D008892:Milk / Q000737:chemistry*; D011374:Progesterone / Q000032:analysis*; D020349:Surface Plasmon Resonance
chemical_list: D011374:Progesterone; D006046:Gold
keywords: Biosensor; Competitive inhibition assay; Fiber optics; Progesterone; Surface plasmon resonance