Other

Roche Diagnostics Operations, Inc.

Roche Diagnostics Gmbh

Eth Zurich

F. Hoffmann-la Roche Ag

Jürg Dual

Olivier Elsenhans

Sven Panke

Frank May

Vuk Siljegovic

Albrecht Haake

Markus Brunner

Peter Ruppen

Robin Vujanic

Lukas Bestmann

Tobias Brack

Klaus Häusler

Michael Sebastian Gerlt

Vulk Siljegovic

The invention relates to a method for determining the reactive state of a chemical reaction process in a reaction mixture (), in particular an amplification reaction for nucleic acids. The method comprises a viscosity determination, which preferably uses a dynamic viscometer (). The invention also relates to an improved dynamic viscometer () for carrying out said method. The viscometer is characterised by an appropriate choice of material for the resonator () and optimised geometric ratios.

Chemical analysis using dynamic viscometry

A method and a micropipetting apparatus is described for dispensing a liquid volume into a vessel via pipetting needle without any contact between the needle and a liquid contained in the vessel. The method comprises forming a drop at the delivery tip of the pipetting needle, the drop being retained at the tip by adhesion forces, and ejecting the drop from the tip of the pipetting needle by focusing at the tip of the pipetting needle a mechanical excitation wave applied at an excitation point at some distance from the tip of the pipetting needle. The apparatus comprises a pipetting needle, an electromechanical transducer mechanically connected with said pipetting needle for mechanically exciting the pipetting needle with a pulse of mechanical waves that propagate through the needle, and an electrical signal generator for generating an excitation pulse signal and for applying this signal to the electromechanical transducer.

Pipetting needle

The invention covers the field of positioning of small particles () in a fluid (). Disclosed is a method by which small particles () are positioned by a sound field. For generating the sound field an apparatus contains a plate () excited to vibrations by a transducer () and a reflecting body with a rigid surface (). A mounting () holds the vibrating plate () and the transducer (). The particles will be concentrated at predetermined positions either at the rigid surface of the reflecting body () or levitating in the fluid (). Due to the fact that the sound waves are emitted by the vibrating plate particles can be positioned in entire area between the vibrating plate and the reflecting body.

Method for positioning small particles in a fluid

A level sensor apparatus is disclosed for detecting contact of a pipetting needle with a liquid contained in a vessel. The apparatus includes a sensor head made up of a pipetting needle, a needle holder, and an electromechanical transducer. The sensor head also has an associated mechanical resonance frequency. An electrical signal generator is used to generate a driving signal which when applied to the electromechanical transducer causes vibration of the pipetting needle at the resonance frequency. A measurement device is used to measure a parameter of a vibration signal indicative of the mechanical vibration of the pipetting needle when it is driven by the driving signal. An electronic circuit and associated computer software is provided to evaluate variation of the vibration signal with time and thus detect contact of the pipetting needle with a liquid contained in the vessel.

Level sensor apparatus for detecting contact of a pipetting needle with a liquid in a vessel

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Zumikon, Switzerland

Jürg Dual