Manganese tetraarylthiosubstituted phthalocyanines (complexes 1-5) have been deposited on Au electrode surfaces through the self assembled monolayer (SAM) technique. SAM characteristics reported in this work are: ion barrier factor (similar to 1); interfacial capacitance (303-539 mu F cm(-2)) and surface coverage (1.06 x 10(-10)-2.80 x 10(-10) mol cm(-2)). Atomic force microscopy was employed in characterizing a SAM. SAMs of complexes 1-5 were employed to detect L-cysteine (with limit of detection ranging from 2.83 x 10(-7) to 3.14 x 10(-7) M at potentials of 0.68-0.75 V vs. Ag vertical bar AgCl) and nitrite (limit of detection ranging from 1.78 x 10(-7) to 3.02 x 10(-7) M at potentials of 0.69-0.76 V vs. Ag vertical bar AgCl). (C) 2009 Elsevier Ltd. All rights reserved.