All lenses that were cultured following cleaning yielded no colonies. aeruginosa formed on the lenses by the above methods varied from 10(6)-10(13) cells/mL. The experiments were performed in triplicate. Both the sample lenses after disinfection and the control lenses were immediately placed in LB broth for outgrowth and measured by standard cell-counting methods. Inoculated lenses were then cleaned and disinfected, according to directions for AMO Easy Rub™ and Alcon No Rub™, rubbed and rinsed with saline for contact lenses (the brand made a difference in the experiment), followed by measurement of the effectiveness of the disinfection procedure with the intrinsic fluorescence instrument. Intrinsic fluorescence of Acuvue™ contact lenses (samples and controls) was measured before and after incubation with P. Our aim is to show that intrinsic fluorescence measurements can yield real-time, critical information about the efficacy of contact lens decontamination products and protocols. The disinfection performance of AMO Easy Rub™ and Alcon No Rub™ contact lens solutions was compared with CVS-brand saline for contact lenses on contact lenses contaminated with Pseudomonas aeruginosa (ATCC 10145). This approach is sensitive (10 cells), requires no added reagents or sample contact, and measurements can be made in near real time. We have monitored microbial contamination on surfaces and in fluids by intrinsic fluorescence of microbes and distinguished their metabolic states (viable cells, nonviable cells, and endospores). The efficacy of disinfection of contact lenses is difficult to determine. By using this method, a wide range of microorganisms such as bacteria, protozoa, amoebae, fungi and other microorganisms can be detected These fluorophores include reduced pyridine nucleotides (RPNs), flavins, and cytochromes to distinguish live cells cytochromes for dead cells and calcium dipicolinic acid (DPA) for spores. By monitoring the fluorescence of cellular components of microorganisms, their concentrations and metabolic states (live, dead, spores) can be determined. The detection limit of the instrument designed specifically for this purpose and reported here is ~50 bacterial cells/L. By using intrinsic fluorescence, microbial contamination in water can be monitored in real-time, continuously, without sample collection or contact and at very low concentration. However, our current monitoring methods for drinking water do not provide fast and reliable results to deal with these challenges. In some extreme cases, such as Arizona, the population may have to switch and use recycled toilet water for potable use in the near future. With the rapid increase in global population, geographically changing drought conditions and the ensuing potential water shortage, water quality has become a major concern.
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