Background: Gastroesophageal reflux disease (GERD) is a common chronic gastrointestinal
disorder in adults that occurs as the stomach contents reflux and come up into the esophagus
due to a dysfunction in the lower oesophageal sphincter. One approach commonly used to treat
GERD is inhibition of the activity of pepsin enzyme. Carbon nanotubes (CNTs) are nanoparticles of
carbon atoms that possess numerous interesting physical and chemical properties. CTNs functionalization
expands the range of their properties to make them soluble in biological fluids and to confer
the property of carrying drug or biological macromolecules which increase the scope of their applications
in biomedical science.
Objective: This study aims to utilize CNTs as a pepsin inhibitor and as a new medication for the
treatment of GERD.
Methods: The pepsin activity before and after the addition of an exact amount of the CNTs to the reaction
mixture was measured colorimetrically.
Results: The results showed that both Vmax and Km changed after the addition of CNTs to the pepsin
solution indicating a mixed inhibition of pepsin activity. This finding pointed to the ability of
CNTs to bind with the pepsin molecule and pepsin-protein complex, therefore inhibiting the enzyme
Conclusion: The findings also demonstrated a complete inhibition of pepsin activity by CNTs when
increasing the ionic strength of the reaction mixture. It can be inferred that using CNTs at a high concentration
of NaCl at 37°C is the optimal condition for pepsin inhibition.