# Incorporating Real World Experiences in an Undergraduate Biochemistry Laboratory CourseDetection of Gluten in Food and Beverages Using an Enzyme-Linked Immunosorbent Assay

## TL;DR

This paper describes a lab experiment for undergraduate biochemistry students to detect gluten in food using ELISA, simulating real-world applications.

## Contribution

The study introduces an optimized ELISA-based lab protocol suitable for time-limited undergraduate settings.

## Key findings

- A direct ELISA method was optimized to detect gluten in food within a 2.5-hour lab session.
- Multiple substrates were tested to identify the most efficient for gluten detection.
- The experiment successfully demonstrated real-world applications of biochemistry techniques.

## Abstract

Celiac disease (CD), an autoimmune disease affecting
1% of the
global population, is caused by the consumption of gluten. Gluten
is a storage protein that is found in wheat, rye, and barley. The
addition of gluten to food products imparts unique viscous and elastic
characteristics in foods such as bread. The only recommended treatment
for celiac disease is a gluten-free diet. The consumption of gluten-free
labeled food products reduces the risk of an autoimmune response and
other symptoms associated with celiac disease, including anemia, dermatitis
herpetiformia, osteoporosis, muscle weakness, ataxia, and coagulopathy.
The Codex Alimentarius and Food and Drug Administration (FDA) state
that gluten-free foods must limit gluten content to 20 ppm. Using
an enzyme-linked immunosorbent assay (ELISA), quantitative studies
can be performed to detect the concentration of gluten present in
gluten-free food products. This work uses a direct ELISA to quantify
the amount of antigen (gluten) present by measuring absorbance in
gluten-containing and gluten-free food products. A color gradient
was observed based on the increasing concentration of gluten present
in each gluten standard. Multiple substrates (o-phenylenediamine,
3,3′,5′-tetramethylbenzidene, aminosalicylic acid, and
2,2′-azino-bis­(3-ethylbenzthiazoline-6-sulfonic-acid)) were
used to determine the most efficient method for incorporating this
technology in an undergraduate biochemistry laboratory experiment
where time is restricted and resources may be limited. This experiment
was optimized to complete this assay within a 2.5 h lab period, thereby
demonstrating a real world application using traditional biochemistry
techniques and enhancing the students’ laboratory skill set
and critical thinking skills.