This book is based on practical experience and is therefore written as a prac­ tical manual. The fore-runners of the book were the manuals of the first and second EMBO-Courses on "Micromethods in Molecular Biology" which were held in G6ttingen in the spring of 1970 and the autumn of 1971. This book may serve as a manual not only for the participants of the third EMBO-Course to be held in G6ttingen in autumn 1973, but also for all experimenters who are interested in using micromethods. It must be emphasized from the outset that this book is conceived as a "cook book" and not as a monograph which attempts to revue the literature on micromethods critically. The methods described here in detail are performed routinely in the authors' laboratories and include all the practical details necessary for the successful appli­ cation of the micromethods. There are many other sensitive and excellent micro­ methods which are not included in this book, because the authors feel that in a "cook book" only methods for which they have personal experience and profi­ ciency should be described. Some readers may feel that the title promises more than the present contents of this book; however, if sufficient interest is shown in this volume, it may be possible to remedy such deficiencies in future editions.

1 Micro-Electrophoresis on Polyacrylamide Gels.- Micro-Disc Electrophoresis.- Microanalysis of DNA-Dependent DNA-Polymerase.- Microanalysis of DNA-Dependent RNA-Polymerase.- Quantitative Assay for Dehydrogenases.- Micro Isoelectric Focusing.- Micro-Electrophoresis on Gradient Gels.- Concluding Remarks.- Literature.- 2 Micro-Determination of Amino Acids and Related Compounds with Dansyl Chloride.- Dansylation Reaction.- Preparation of the Stock Solution of Dansyl Chloride.- Dependence of the Dansyl Reaction on pH.- Dependence of the Dansyl Reaction on the Incubation Time.- Practical Procedure.- Identification of Dansyl Derivatives.- Characterization of tRNA.- Determination of C- and N-Terminal Amino Acids.- Determination of Amino Acids from Biological Material.- Determination of Mono-Amines.- Concluding Remarks.- Literature.- 3 Micro-Determination of Phospholipids.- General Remarks.- Calibration Curves.- Analysis of Biological Material.- Biological Applications.- Literature.- 4 Micro-Diffusion Techniques.- Two-Dimensional Micro-Immunodiffusion.- Characterization of a Polymerase-Template Complex by Two-Dimensional Micro-Diffusion.- Radial Micro-Diffusion.- Micro Antigen-Antibody Crossed Electrophoresis.- One-Dimensional Multi-Stage Micro-Immunoelectrophoresis.- Literature.- 5 Capillary Centrifugation.- Preparative Capillary Centrifugation.- Analytical Capillary Centrifugation.- Literature.- 6 Micro-Electrophoresis for RNA and DNA Base Analysis.- Biological Material.- Procedure for the Measurement of a Volume.- Extraction of Nucleic Acids.- Medium for Electrophoresis.- Biological Applications.- Literature.- 7 Determination of the Dry Mass of Small Biological Objects by Quantitative Electron Microscopy.- Prerequisites.- From Sample to Result.- Preparing an Object for Quantitative Electron Microscopy.- Summary.- Literature.- 8 The Construction and Use of Quartz Fiber Fish Pole Balances.- Optical Measurements.- The Choice and Manufacture of Suitable Quartz Fibers.- Making the Fiber.- Balance Cases and Final Assembly.- Mounting the Balance.- Weighing.- Calibration.- Weight Correction for Adsorption of Gases and Moisture in Tissues.- 9 Microphotometry.- Preface.- Photometry.- Photometers.- Microphotometry.- Microphotometers.- Spot Measurements.- Line Scanning.- Area Scanning.- Addendum.- Literature.- 10 Cytofluorometry.- Description of Instrument.- Fluorescence Standard.- Use of Instrument.- Some Applications.- Analysis and Evaluation of Data.- Literature.- 11 Quantitative Autoradiography at the Cellular Level.- Biochemical Aspects.- The Nuclear Emulsion.- The Autoradiograph.- Preparing the Samples.- Quantitative Determination of Substances.- Manual and Automatic Methods of Grain Counting.- Application. The Rate of Synthesis of DNA in Individual Cells.- Literature.- 12 Micro-Dialysis.- Micro-Dialysis Chamber.- Micro-Electrodialysis.- Equilibrium Dialysis.- Literature.- 13 Micro-Homogenisation.- Literature.- 14 Wet Weight Determination in the Lower Milligram Range.- Literature.- 15 Micro-Magnetic Stirrer.- 16 Production of Capillary Pipettes.- Literature.