Yadid-Pecht, OrlyTurner, Raymond J.Kuri Martinez, Juan Carlos2022-09-262022-09-262022-09-22Kuri Martinez, J. C. (2022). Methodological analysis of an improved gluten quantitation aptamer-based biosensor (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca.http://hdl.handle.net/1880/115284https://dx.doi.org/10.11575/PRISM/40290Fluorescence resonance energy transfer based aptamer are currently being studied in many research groups due to their potential contribution as an alternative gluten standard for gluten- quantitation. The current gold standard withholds critical limitations due to the nature of the system, hence this aptamer-based sensor (or aptasensor for short) application represents one of the alternatives; yet, drawbacks such as low signal-to-noise ratio and reliability are in the scope of research groups aiming to overcome them. In this study, multiple variations of the protocol are assessed based on correctly classifying food samples as their actual concentration of gluten, this is coined as the accuracy of the biosensor. The study also aims to overcome the current limitation of the gold standard in fermented samples by including soy sauce and malt vinegar in the tests. And different additives aiming to help overcoming the limitation were implemented into the protocol and assessed. This approach allowed the biosensor to classify the products with 98.28% of accuracy, and 0% of error in classifying gluten-rich products (false-negatives) within the first 3 days of bioassay preparation; yet, this bioassay needs to be studied further as only 18 different off-the-shelf products were tested (over 800 tests in total). Additionally, after the first week, false-negatives increased to around 5% and remained that way until the end of the first month. The cause of this relies mostly on the decomposition of the conjugate reduced graphene oxide and polyethylene glycol that are implemented in the system. This implies that further research aiming solely at additives or alternative reagents that increase the lifespan or stability of the conjugate would augment the overall performance.engUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.AptamerFluorescenceFRETGluten sensor33-mer peptideAptasensorGraphene oxideELISAEducation--HealthEducation--TechnologyFood Science and TechnologyBiochemistryEngineering--BiomedicalEngineering--Chemicalmaster thesis