Flow Injection Determination of Antibacterial Drug Trimethoprim in Pharmaceutical Preparations with Tris(2,2 -Bipyridyl)Ruthenium(III) Chemiluminescence

In the present study, a simple and sensitive chemiluminescence method using tris(2,2 - bipyridyl)ruthenium(lll) with flow injection detection is reported for the analysis of trimethoprim in pharmaceutical preparations. The calibration graph was linear over the concentration range of 0.05- 5.0 μg/mL^-1 with relative standard deviations (n = 4) in the range 1.0 - 2.5%. The limit of detection (3(Sigma) blank) was 0.008 μg /mL^-1 with a sample throughput of 100 h^-1. The effect of some organic compounds, common excipients used in pharmaceutical preparations, cations anions were studied for trimethoprim determination. Ru(bipy)32+ was chemically oxidized to Ru(bipy)33+ online using lead dioxide mini column.