Use of a sequential injection technique for mechanistic studies and kinetic determination of bromazepam complexed with iron(II) in hydrochloric acid

For the first time a sequential injection technique has been employed in a full kinetic investigation as well as for a kinetic procedure utilizing the fixed-time method. The complexation reaction of bromazepam with iron(II) in hydrochloric acid was studied using spectrophotometric detection at λ(max) 585 nm for the product formed. A rate law was offered, which was found to be consistent with the postulated reaction mechanism. From the observed kinetics it was found that the fixed-time method utilized at 100 s using 0.0100 mol dm^-3 iron(II) and 0.0115 mol dm^-3 HCl had optimal conditions for the determination of bromazepam in the range 5.0 x 10^-4-1.5 x 10^-3 mol dm^-3. The method was found to be suitable for the determination of bromazepam in drug formulations.