Multiplexed, rapid, point of care device to quantify allergen-specific IgE

Allergy is a disorder of the immune system characterized by a maladaptive immune response to harmless environmental antigens (“allergens”). Allergy affects nearly 40–50 million people in the US, with total estimated costs attributable to asthma care at $19.7B [1,2]. Phadia AB is the market leader in allergy in vitro diagnostics with the ImmunoCAP ISAC chip (not current FDA approved in the US). We have identified two specific shortcomings with this IVD technology. First, the ISAC “biochip is a solid substrate built from a glass plate” which reduces the fluorescence yield of the labels used in sensing, whereas significant signal enhancement is readily available by utilizing simple and inexpensive layered surfaces. The missed opportunity of increasing the signal by more than an order of magnitude results in requiring sophisticated fluorescent readers. Second, the measurements are not quantitative — the allergen spots are not calibrated and have very high variability in mass of spotted protein, which affects specific IgE capture and quantization. Thus, a need exists for a calibrated, sensitive allergy microarray platform that is combined with enhanced detection techniques for a rapid, point-of-care instrument.