Polymer films having a printed self-assembling monolayer

The present invention comprises methods of contact printing of patterned, self-assembling monolayers of alkanethiolates, carboxylic acids, hydroxamic acids, and phosphonic acids on thermoplastic films metallized with an alloy such as nickel/gold, the compositions produced thereby, and the use of these compositions. Patterned self-assembling monolayers allow for the controlled placement of fluids thereon which contain a chemically reactive, indicator functionality. The optical sensing devices produced thereby when the film is exposed to an analyte and light, can produce optical diffraction patterns which differ depending on the reaction of the self-assembling monolayer with the analyte of interest. The light can be in the visible spectrum, and be either reflected from the film, or transmitted through it, and the analyte can be any compound reacting with the fluid on the self-assembling monolayer. The present invention also provides a flexible support for a self-assembling monolayer on a metal alloy.