Smartphone instrument for portable enzyme- linked immunosorbent assays

Abstract

We demonstrate the utilization of a smartphone camera as a spectrometer that is capable of measuring Enzyme Linked Immunosorbent Assays (ELISA) at biologically-relevant concentrations with the aid of a custom cradle that aligns a diffraction grating and a collimating lens between a light source and the imaging sensor. Two example biomarkers are assayed using conventional ELISA protocols: IL-6, a protein used diagnostically for several types of cancer, and Ara h 1, one of the principle peanut allergens. In addition to the demonstration of limits of detection at medically-relevant concentrations, a screening of various cookies was completed to measure levels of peanut cross-contamination in local bakeries. The results demonstrate the utility of the instrument for quantitatively performing broad classes of homogeneous colorimetric assays, in which the endpoint readout is the color change of a liquid sample.

Immunosensing procedures for carcinoembryonic antigen using graphene and nanocomposites

“…A compact colorimetric and fluorometric reader (Mudanyali et al, 2012), as well as a CP-based compact EC sensing platform, have been reported (Lillehoj et al, 2013). Indeed, it is feasible for colorimetric readout from a 96-well microtiter plate (MTP) using a CP device (Vashist et al, 2015a, Vashist et al, 2015b and the measurement of a full emission spectrum of any light emitter using a CPbased fluorimeter (Long et al, 2014, Yu et al, 2014. Together with graphene as a sensing interface, the CP-platform doubtlessly provides cost-effective mobile healthcare and personalized medicine with widespread applications for point of care testing (POCT) (Vashist et al, 2015c).…”

Instrumenting smartphones with portable NIRS

“…To this end, custom solutions can be developed and paired with the devices. For instance, an example of a custom sensing solution that can detect protein and allergens is explored by Long et al [11]. Their setup allows the user to extract the physical parameters of a sample and achieve high precision fingerprinting.…”

Mobile Device Based Water Monitoring with Single Reference Image

“…With the help of 3D printers, smartphone spectrometer systems found wide range of colorimetric measurements application for chemical and biological analytes [3]. Some of them are water quality sensing for environment [4,5], leaf color analysis for agriculture [6], pH [7,8] and glucose [9] sensing, and peanut allergen detection [10]. Color data is mostly used in paper based sensors application where parameters from various color spaces, i.e.…”