Enzyme-Linked Immunosorbent Assay-Based Microarray on a Chip for Bioaerosol Sensing: Toward Sensitive and Multiplexed Profiling of Foodborne Allergens

Abstract

Food allergy has become a growing health concern that may impair life quality and even cause life-threatening outcomes. Accidental and continuous exposure to allergenic bioaerosols has a substantially negative impact on the respiratory health of patients. Traditional analytical methodologies for food allergens are restricted by strong reliance on bulk instrumentation and skilled personnel, particularly in low-resource settings. In this study, a fluorescent sensor array based on the enzyme-linked immunosorbent assay performed on a herringbone-shaped microfluidic chip (ELISA-HB-chip) was designed for dynamically sensitive and multiplexed quantification of foodborne allergens in aerosols that originated from liquid food extracts. Due to the high surface area of aerosol particles and sufficient mixing of immunological reagents using a herringbone micromixer, the detection sensitivity was improved by over an order of magnitude compared to traditional allergen detection in the aqueous phase. Through fluorescence imaging of multiple regions on the ELISA-HB-chip, four important foodborne allergens, namely, ovalbumin, ovomucoid, lysozyme, and tropomyosin, could be simultaneously monitored without any cross-reactivity, and the limits of detection for these allergenic species were determined to be 7.8, 1.2, 4.2, and 0.31 ng/mL, respectively. Combining with a 3D printed and portable fluorescence microscope, this platform exhibited an excellent field-deployable capacity for quick and accurate determination of allergens in the aerosol state from spiked buffer solutions, thus displaying the practicality for food safety screening at cooking or food processing sites where patients are potentially under exposure to allergenic bioaerosols that escaped from food matrices or extracts.

Wearable, Biocompatible, and Dual-Emission Ocular Multisensor Patch for Continuous Profiling of Fluoroquinolone Antibiotics in Tears

“…For noninvasive and continuous analysis of antibiotic residues in tears, a smartphone-based fluorescent imager (15.8 × 7.6 × 10.0 cm 3 ) was adapted from our prior prototype for sensing microtube-based solutions, which now allows for imaging paper-based sensor spots on a chip. 51 The UV laser, sample holder, and camera were finely aligned and positioned in the 3D-printed attachment to acquire an optimal imaging performance (Figure 3i,j). An optical filter, with a cutoff wavelength of 420 nm, was employed to reduce the background noise from the excitation light.…”

“…Conventional assays presenting to the hospital fail to reach the goal due to delayed diagnostic feedback or heavy dependence on the central laboratory. For noninvasive and continuous analysis of antibiotic residues in tears, a smartphone-based fluorescent imager (15.8 × 7.6 × 10.0 cm 3 ) was adapted from our prior prototype for sensing microtube-based solutions, which now allows for imaging paper-based sensor spots on a chip . The UV laser, sample holder, and camera were finely aligned and positioned in the 3D-printed attachment to acquire an optimal imaging performance (Figure i,j).…”

Smartphone-Based Fluorescent Profiling of Quaternary MicroRNAs in Urine for Rapid Diagnosis of Urological Cancers Using a Multiplexed Isothermal Exponential Amplification Reaction

“…The analytical performance of the proposed method was assessed by calibrating each miRNA in individual EXPAR alone and then validating it in the homogeneous MEXPAR mixtures. As a supplement to our toolbox for on-site biomarker (including proteins, biogenic amines, and nucleic acids) imaging, we subsequently developed a smartphone-based fluorescent detector for portable quantification of various miRNAs in low-volume urine samples (∼5 μL) and for field diagnosis of urological cancers (Figure S7a). The fluorescence detector consists of a 254 nm ultraviolet lamp, a set of four switchable optical filters (green, yellow, orange, and red), a 3D-printed attachment, and a smartphone reader, for polychromatic fluorescent imaging of quaternary miRNAs in at most eight microtubes simultaneously (Figure S7a).…”

Ratiometric Fluorescence Aptasensor of Allergen Protein Based on Multivalent Aptamer-Encoded DNA Flowers as Fluorescence Resonance Energy Transfer Platform

“…), fish, eggs, nuts, and wheat, are responsible for 90% of food allergic reactions. Therefore, the Food and Agriculture Organization of the United Nations (FAO)/World Health Organization (WHO) defined it as the most common food allergens. − Ara h1, the predominant allergenic protein in peanuts, is specifically acknowledged as a major concern owing to its distinctive trimeric structural configuration and widespread distribution characteristics. , The anaphylaxis triggered by Ara h1 is a typical food allergy reaction, which occurs both in children and adults, and even trace amounts of Ara h1 can cause severe allergic symptoms in allergic individuals. − So far, food allergies still cannot be completely cured, making stringent avoidance of allergen-containing foods is the preferred strategy to safeguard allergic individuals from anaphylaxis. , Thus, it is an urgent need to develop an efficient method to trace analysis of Ara h 1 in food for allergen labeling, dietary guidance, and ultimately preventing allergic incidents. − …”