Determination of Meropenem by Spectrophotometric-Application to Pharmaceutical Preparations

.cm 1,Sandellʹs sensitivity index is 0.0161μg.cm 2,The method is precise (relative standard deviation RSD% is better than ±3.32%) and accurate (relative error in the range of -0.97 to-0.60%) depending on the concentration level. The method was applied succefully to the assay of Meropenem in pharmaceutical preparation in the form of injection. 1Introduction Meropenem (MER) Fig. (1) is abroad –spectrum antibacterial agent, with activity against the majority of gram positive, gram negative and anaerobic bacteria, MER is colorless to white crystals. springily soluble in water, very slightly soluble in alcohol. practically insoluble in acetone and in ether [1].MER (t 1⁄2 ,1h) is similar to imipenem but it is stable to renal dihydroperptidase[2]. MER was determined in pure and pharmaceutical formations by formation of dark yellow colored product between MER and 1,2-naphthoquinone-4sulphonic acid measured at 449 nm in basic medium[3].The drug was determined by formation of a color red chromogen with brucine and sodium periodate in acidic medium, the maximum absorption was at 523 nm ,Beer ' s law was obeyed in the range of concentration between(2-12μg/ml)of MER the apparent was 0.07μg.cm 2[4]. The stability of the drug has been studied at two temperatures 4.25 oC and 40oC in both acidic and basic medium using UV spectrophotometric technique at 280 nm. [5]. An ion pair between MER and bromothymol and bromocresol at (420and 418) nm was studied respectively. The method was sensitive but need to extraction steps[6]. Other methods were used for determination of MER based on chromatographic procedures were also reported[7,8,9,10,11]. 2,3-dichloro-5,6-dicyano 1,4-benzoquinon has been used for determination of domperidoe. The formed complex exhibits maximum absorption intensity at 458 nm in acetonitrile and 394nm in chloroform[12]. The present study included determination of MER as a π-electron donor, with 2,3-dichloro 1,4dicyanobenzoquinon as an acceptor, and applied the method to determine MER in pharmaceutical preparations. Chemically MER is 3-[5(dimethylcarbamoyl) pyrrolidin-2-yl] sulfanyl-6-(1hydroxyethyl)-4-methyl-7-oxo-1-azabicyclo[3.2.0] hept-2-ene-2-carboxylic acid with the following structure [13].