Publication

Abstract : THC and its metabolites are detectable in body fluids and could be used to detect marijuana use. This research work reveals the possibility of using a carbon nano tube (CNT) based enzyme sensor for the detection of 9-carboxy tetrahydrocannabinol (9 THC-COOH) in urine using a cysteine protease obtained from papaya plant called papain. A comparative study of armchair and zigzag conformation of CNTs with the protein was carried out and the suitable conformer of CNT has been identified. The electrostatic energy variations and the thermodynamic energy differences of CNTs have been computed. A characteristic gradient in electrostatic potential has been identified for the CNT-protein complexes which could be effectively sensed using electrochemical sensors. The computational analysis of CNT-papain interaction supports the possibility of developing a biosensor using papain coated carbon nano tubes for the detection of THC-COOH in urine of the suspected marijuana consumed persons. A comparative analysis of the interaction energies of arm-chair and zig-zag conformations of carbon nano tubes with the cysteine protease enzyme papain has been carried out. The arm chair conformation with configuration index 18, 18 (m, n) has been identified as keeping the highest interaction energy of 45.218 kcal/mol. With this conformer designing of an electrochemical sensor has been suggested.