Atomic force microscopic and electrochemical characterization of the modified screen printed carbon electrode by self assembled deposition of chitosan and activated carbon

Abstract

The surface topographic characteristics generated after a modification of screen printed carbon electrode (SPCE) with either chitosan or activated carbon blending chitosan were closely investigated by atomic force microscopy and a complementary electrochemical techniques. Eighty five percent deacetylation degree chitosan was used at 1% in 1% acetic acid while the activated carbon blending ratio used was 1:1 in chitosan solution. The modification was performed via self assembled deposition directly onto the working electrode surface area. Growth feature of each modified surface was obviously differentiated by all roughness parameters such as an average roughness, root mean square, height different, grain and fractal. The highest roughness value with the least grain was from chitosan modified SPCE. A good correlation result was obtained with electrochemical cyclic voltammetry that a great change in current response was also appeared. Both the modified SPCE by chitosan and activated carbon blending chitosan could produce comparable higher current sensitivity with up to around 0.5 slope value following by their regression coefficient of 0.99. Thus affordable and efficient platforms for a fabrication of desirable pesticide biosensor could be achieved with these modifications as expected.