Development of an electrochemical biosensor for detection of the BCM-7 opioid peptide from milk protein A1

• Grant number: 25/05727-3
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: January 01, 2026
• End date: December 31, 2028
• Field of knowledge: Biological Sciences - Biophysics - Molecular Biophysics
• Principal Investigator: Eduardo Festozo Vicente
• Grantee: Lorenza Eivazian Vianna Nogueira Brandão
• Host Institution: Faculdade de Ciências e Engenharia. Universidade Estadual Paulista (UNESP). Campus de Tupã. Tupã , SP, Brazil
• Associated research grant: 21/06706-9 - Antimicrobial peptides: expanding the horizons for animal production performance optimization, AP.JP2

Abstract

Brazil is the fourth largest milk producer in the world, and in 2023 the country produced around 24.52 billion liters of raw cow's milk. However, the consumer market for this food is increasingly demanding due to the high incidence of dietary restrictions. Around 40% of the tends to develop lactose intolerance (CID E73) in Brazil, and this causes the demand for medicines that contain the lactase enzyme to increase more and more. However, in some cases, the symptoms do not stop even after taking the medication. Given this, studies have shown that the peptide ¿-casomorphin-7 (BCM-7), released during the ingestion of the A1 ¿-casein protein present in the milk of cows with the A1A1 or A1A2 genotype, can lead to effects that favor inflammation and gastrointestinal motility. In addition, in some individuals, BCM-7 activates the neuropeptide/µ-opioid receptor called ¿-endorphin, found in the gastrointestinal tract, and causes effects similar to the use of narcotics. Therefore, the present study will initially aim to synthesize the A1 and A2 proteins in vitro using the Solid Phase Peptide Synthesis (SPFS) technique. Next, the A1 protein will undergo enzymatic digestion with the enzyme elastase, responsible for the site-specific cleavage that produces the BCM-7 peptide, to be identified in milk samples and dairy products. The next step will be to develop an electrochemical biosensor capable of detecting the A1 protein in cow's milk. Furthermore, it will be verified whether the biosensor can identify BCM-7 in milk after enzymatic digestion. Validation of the study will include individual tests with genotyped cows (A1A1, A1A2 and A2A2) and through sensitivity tests using serially diluted samples of A1 milk in A2 milk and A1 and A2 proteins synthesized in the laboratory. Sensitivity tests will also be carried out on samples of dairy products, such as cheese and yogurt. Finally, the sensitivity of the biosensor will be evaluated in comparison to DNA-based tests. (AU)