Molecular diagnosis of Pseudomonas aeruginosa contamination in ophthalmic viscosurgical devices

Abstract

Polymerase chain reaction (PCR) was performed to verify the utility of this technique in detecting low levels of microbial contamination in quality control of ophthalmic viscosurgical devices (OVDs). Universal and specific primers (oprL) were applied to identify Pseudomonas aeruginosa as one of the objectionable microorganisms in pharmaceutical products. Samples of hydoxypropylmethylcellulose, sodium hyaluronate inoculated with defined number of Pseudomonas aeruginosa cells and subsequently exposed to boiling for 15 minutes for releasing DNA materials from the contaminants. The treated samples were subjected to PCR amplification. Agarose gel electrophoresis revealed amplified fragments as predicted, with no interference from the products and other environmental bacterial and fungal strains included in the study. The minimum detection limit of Pseudomonas aeruginosa DNA was 2.1 ng. In contrast to conventional culturing methods that require mean of 5 – 6 days for identification of Pseudomonas aeruginosa, the entire mentioned PCR assay lasted about 4 – 5 hours.