2025-04-15https://repository.covenantuniversity.edu.ng/handle/123456789/49496The use of corrosion inhibitors is a major practical method for reducing the corrosion of mild steel in corrosive environments. Weight loss, potentiodynamic polarization (electrochemical) measurements and SEM analyses were used to examine the corrosion inhibition behaviour of calf thymus gland DNA (CTGDNA) in 10% sulphamic acid. Weight loss data demonstrated that the highest inhibition efficiency of 82.71% was reached at 303 K and 6 h of immersion with calf thymus DNA at a concentration of 2.5 mg/L. The electrochemical test, with a change in Ecorr < 85 mV seen in potentiodynamic polarisation curves, verified that CTGDNA functions as a mixed inhibitor, by creating a barrier on the mild steel's surface, it inhibited both the anodic dissolution of the metal and the cathodic oxygen reduction. CTGDNA adsorption on mild steel modelled the Langmuir isotherm with a linear regression coefficient of 0.99. The increase in the activation energy from − 37.54 to 52.5 kJ/mol after 2 h immersion; with a similar trend for 4 and 6 h demonstrated that addition of CTGDNA favoured chemisorption. The small and negative value of entropy was an indication that the adsorption of CTGDNA was spontaneous. SEM images demonstrated that the addition of CTGDNA significantly decreased the mild steel surface deterioration in the uninhibited solution. It is the conclusion of this study that CTGDNA is an effective inhibitor of mild steel corrosion in 10% sulphamic acid.application/pdfQ Science (General), T Technology (General), TP Chemical technologyArticle