Volume 7 No. 2 March – April, 2002 ROMANIAN BIOTECHNOLOGICAL LETTERS – an international journal – CONTENTS 1.G. DAVID, M. DIACONU, G. L. RADU, V. DAVIDInvestigation of the Some Electron Transfer Bioprocesses by Voltammetric Techniques ……………6032.CIUCU, C. CIUCU, R. P. BALDWINOrganic Phase Potentiometric Biosensor for Detection of Pesticides ……………6253.S. FLESCHIN, M. SCRIPCARIU, A.A.BUNACIUA Dynamic Kinetic Model of the Artificial Activated Sludge Process ……………631 4.E. IORGA, N. BELC, A. STANCOV, GH. CAMPEANUImprovement of Falling Number on Romanian Wheat Flours ……………6355.A.A. BUNACIU, S. FLESCHIN, H.Y. ABOUL – ENEINAnalysis Improvement of Drugs Using Modern Methods ……………6476.L. VLĂDESCU, I. BADEA, D. MOJADetermination of Vitamin H1 by the Potentiometric Titration …………… 6557.M. SCRIPCARIU, S. FLESCHIN,V. MAGEARUDetermination of Michaelis Constants for b- Lactamase Reaction by Spectrophotometric Methods ……………6618.A. CIUCU, C. CIUCUOrganic Phase Amperometric Biosensor for Detection of Pesticides ……………6679.M. SCRIPCARIU, S. FLESCHIN, A.A. BUNACIU, V. MAGEARUAnalytical Measurements in Metabolic Changes of Bacterial Medium ……………677 10.I. CAPLANUSElectrical Properties of Some New l-Asparagic Derivatives in Thin-Films ……………681 11.Diary of Events ……………685 Cover: The Bucharest University Building