A standalone notification system, including a notification server which generates electronic messages for alerting customers of potentially fraudulent activity on one or more of their financial accounts. At least one parameter affecting user terminals within a cell is adjusted such that the cell boundary is modified, such that interference in the network is reduced. Capture of the analyte in the pores of the polymer results in a change in the spatial relation of the nanoparticles layered on the polymer, which in turn causes the photochromic optical switch molecules coated thereon to undergo a change in energy state corresponding to a visible change in the optical spectra of the photochromic optical switch molecules. A registry is generated at the first application.