For weak luminescence, quenching of insensitive luminophores by proximity to a gold film improves signal to noise by suppression of background luminescence of Ru(4,7-diphenyl-1,10-anthroline)3Cl2. Initially it was expected that the effects of gold film quenching and nanoparticle enhanced luminescence could be combined to give a summative improvement, but the increase caused by the nanoparticles generates a larger signal to noise ratio and greater sensitivity of those luminophores to the dynamic quenching by gaseous oxygen. Impressive detection limits were achieved on gold coated glass and plain glass, where detection limit was 0.05% and 0.004% and sensitivity 0.02 and 0.05%, respectively.
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