2 research outputs found
Ultrafast Multiplexed-Allergen Detection through Advanced Fluidic Design and Monolithic Interferometric Silicon Chips
A silicon-based miniaturized sensor chip combined with an advanced microfluidic module for the simultaneous, label-free immunochemical determination of four allergens, bovine milk protein, peanut protein, soy protein, and gliadin, is presented. The sensor chip consists of an array of 10 broad-band Mach-Zehnder interferometers (BB-MZIs) monolithically integrated on silicon, along with their respective broad-band light sources. The BB-MZIs were biofunctionalized with the targeted allergens and their responses during immunoreaction were monitored by multiplexing their transmission spectra through an external miniaturized spectrometer. The assay is performed by running mixtures of calibrators or samples with the antibodies against the four allergens followed by an antispecies specific antibodies solution. Employing a fluidic module of nearly one-dimensional geometry, that provided for uniform delivery of the reagents, CV values <6% were achieved for the responses of the 10 BB-MZIs, allowing for reliable multianalyte determinations. The analysis is completed in 6.5 min, and the detection limits were 0.04 μg/mL for bovine k-casein, 1.0 μg/mL for peanut protein, 0.80 μg/mL for soy protein, and 0.10 μg/mL for gliadin. The assays were accurate (recoveries 88-118%) and repeatable (intra- and interassay CVs <7% for all four allergens). Finally, the sensor was evaluated by analyzing samples from a cleaning in place system (CIP) of a dairy industry and the results obtained were in good agreement with those received by the respective ELISAs. The analytical characteristics of the sensor combined with the short analysis time and the small chip size make the proposed system an ideal tool for on-site multianalyte determinations
Ultrafast Multiplexed-Allergen Detection through Advanced Fluidic Design and Monolithic Interferometric Silicon Chips
A silicon-based
miniaturized sensor chip combined with an advanced
microfluidic module for the simultaneous, label-free immunochemical
determination of four allergens, bovine milk protein, peanut protein,
soy protein, and gliadin, is presented. The sensor chip consists of
an array of 10 broad-band Mach–Zehnder interferometers (BB-MZIs)
monolithically integrated on silicon, along with their respective
broad-band light sources. The BB-MZIs were biofunctionalized with
the targeted allergens and their responses during immunoreaction were
monitored by multiplexing their transmission spectra through an external
miniaturized spectrometer. The assay is performed by running mixtures
of calibrators or samples with the antibodies against the four allergens
followed by an antispecies specific antibodies solution. Employing
a fluidic module of nearly one-dimensional geometry, that provided
for uniform delivery of the reagents, CV values <6% were achieved
for the responses of the 10 BB-MZIs, allowing for reliable multianalyte
determinations. The analysis is completed in 6.5 min, and the detection
limits were 0.04 μg/mL for bovine k-casein, 1.0 μg/mL
for peanut protein, 0.80 μg/mL for soy protein, and 0.10 μg/mL
for gliadin. The assays were accurate (recoveries 88–118%)
and repeatable (intra- and interassay CVs <7% for all four allergens).
Finally, the sensor was evaluated by analyzing samples from a cleaning
in place system (CIP) of a dairy industry and the results obtained
were in good agreement with those received by the respective ELISAs.
The analytical characteristics of the sensor combined with the short
analysis time and the small chip size make the proposed system an
ideal tool for on-site multianalyte determinations