Date of Award
The detection and quantification of explosive compounds is extremely important in global security, antiterrorist, and forensic activity. While there are sensitive and reliable methods for detection, the development of electrochemical techniques is used here because they are simple, affordable, and can be made for field use. In this investigation, chlorogenic acid (CGA) modified glassy carbon electrode (GCE) was used to detect hydrazine in concentrations as low as 0.05mM; aspartic acid modified GCE was used to detect both nitrobenzene and 4-nitrotoluene in concentrations as low as 3.3Î¼M and 1.3Î¼M, respectively; and finally phenol red coated GCE was used to detect nitrobenzene in concentrations as low as 3.3Î¼M. The CGA modified GCE showed high redox activity at a pH of 7.5 and could detect hydrazine at scan rates as high as 100mV/s. The aspartic acid coated electrode showed high redox activity between a pH of 5.01 and 6.84 and could detect the nitrobenzene and 4-nitrotoluene at scan rates as high as 100mV/s. The phenol red coated electrode was effective between pH of 5-6 and could detect the nitrobenzene at scan rates as high as 130mV/s. Effects of surfactants such as SDS, DTAB, and DTAC were studied on analytes and their electrochemical activities observed. Overall, the surfactants showed a decrease effect in the current density. The durability of these films on electrodes was also studied. Both the CGA and aspartic acid films showed an immediate and steady decrease in function as successive scans were carried out. This decrease in function could be attributed to degeneration of thin coatings of the film with time. Phenol red coated GCE showed good stability for 15 scans.
D, Hollis Rachial, "The Electrochemical Detection Of Explosive Compounds Using Polymer And Chemically Modified Electrodes" (2014). Theses. 194.