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45it may be attributed to the reduction of -C=O- centre. Based on thehigh adsorptive character of PB onto the mercury elec trode, a validateddirect square-wave cathodic adsorptive stripping voltam metricand differential pulse cathodic adsorptive stripping voltammetricprocedure has been developed for the determination of drug in bulkform and pharmaceutical formulations. The proposed SWCAdS andDPCAdS voltammetric methods allow quantitation over the range100 ng mL –1 –72 µg mL –1 and 1–80 µg mL –1 with detection limit of20.7 and 32.3 ng mL –1 , respectively. The procedure was applied tothe assay of the drug in tablets form with mean percentage recoveriesof 100.1% with SWCAdSV and 99.99% with DPCAdSV. Precisionand accuracy were also checked and were within the limits. Thepeak current was linear with the drug concentration and percentagerecovery was found to be good.Journal of Electroanalytical Chemistry 648 (2010) 20–27Literature references on stability measurementsEvaluation of the oxidative stability of diacylglycerolenrichedsoybean oil and palm olein under Rancimatacceleratedoxidation conditionsYong Wang, Mouming Zhao, Shuze Tang, Keke Song, Xue Han andShiyi OuThe oxidative stability of diacylglycerol (DAG)-enriched soybeanoil and palm olein produced by partial hydrolysis using phospholipaseA1 (Lecitase Ultra) and molecular distillation was investigated at 110°C by the Rancimat method with and without addition of syntheticantioxidants. Compared with triacylglycerol oils, the DAG-enrichedoils displayed lower oxidative stability due to a higher content ofunsaturated fatty acids and a lower level of tocopherols. With theaddition (50–200 mg/kg) of tert-butylhydroquinone (TBHQ) or ascorbylpalmitate (AP), the oxidative stability indicated by induction period(IP) of these DAG-enriched oils under the Rancimat conditions wasimproved. The IP of the diacylglycerol-enriched soybean oil in creasedfrom 4.21 ± 0.09 to 12.64 ± 0.42 h when 200 mg/kg of TBHQ wasadded, whereas the IP of the diacylglycerol-enriched palm oleinincreased from 5.35 ± 0.21 to 16.24 ± 0.55 h when the same levelof AP was added. Addition of TBHQ, alone and in combination withAP resulted in a significant (p ≤ 0.05) increase in oxidative sta bilityof diacylglycerol-enriched soybean oil. AP had a positive synergisticeffect when used with TBHQ.Journal of the American Oil Chemists’ Society 87 (2010) 483–491Evaluation of the oxidation stability of diesel/biodieselblendsGeorge Karavalakis, Stamoulis Stournas and Dimitrios KaronisBiodiesel is an alternative fuel derived from vegetable oils, animalfats and used frying oils. Due to its chemical structure, it is moresusceptible to oxidation or autoxidation during long-term storagecompared to petroleum diesel fuel. One of the major technical issuesregarding the biodiesel blends with diesel fuel is the oxidation sta bilityof the final blend, which is, nowadays, of particularly high concerndue to the introduction of ultra low sulphur diesel, in most parts ofthe EU. This study examined the factors influencing the stability ofseveral biodiesel blends with low and ultra low sulphur automotivediesel fuels. The aim of this paper was to evaluate the impact ofbiodiesel source material and biodiesel concentration in diesel fuel,on the stability of the final blend. Moreover, the effects of certaincharacteristics of the base diesels, such as sulphur content and thepresence of cracked stocks, on the oxidation stability are discussed.Fuel 89 (2010) 2483–2489INFORMATION | 2 | 2010-11