Zinc oxide-gold mediates surface-enhancement in Enzyme-linked immunosorbent assay for high-sensitive diagnosing acute pancreatitis

Acute pancreatitis is the condition of an inflammation in the pancreas, occurring due to trauma, abuse, and alcohol consumption. The level of amylase in the blood is as an established marker, regularly looked by physicians for diagnosing pancreatitis. Enzyme-linked immunosorbent assay (ELISA) can be a ‘gold standard’ method to quantify the α-amylase level in the biological fluids. Improving ELISA is mandatory to enhance the detection of α-amylase, herein, zinc oxide (ZnO) nanomaterial modified ELISA-surface was introduced to detect the level of α-amylase. ZnO was immobilized on the ELISA well through alkalinization followed by 3-Aminopropyltriethoxysilane (APTES)-linkage. Anti-α-amylase monoclonal antibody was added on ZnO-modified ELISA well. On the modified surfaces, amylase was sandwiched using mono- and polyclonal-antibodies conjugated gold nanoparticles. This nanomaterials-modified ELISA detects amylase as low as 0.6 ng/mL on a linear regression with 0.5 to 40 ng/mL in the buffer [y = 0.0797x + 0.0849; R 2 = 0.9746]. The amylase was also detected from the saliva samples without any interference, indicates the specificity of method generated. This modified ELISA quantifies a lower level of α-amylase and helps to diagnose acute pancreatitis and the associated issues.