Bruker Daltonik Gmbh

Imperial Cancer Research Technology, Ltd.

Biopsytec Gmbh

Caisley International Gmbh

Ivo Glynne Gut

Jochen Franzen

Alexander Olek

Arno Heuermann

Thomas Claus Dittmann

Stephan A Beck

Arno Svend Heuermann

The invention relates to a method and device for withdrawing biological samples. The device has a receptacle which can receive one or several covers for sample containers, another receptacle which can receive one or several sample containers, and a mechanism. Said mechanism joins the covers and containers together during a working cycle in which the biological sample is withdrawn either through the cover or the sample container to a test capsule.

Method and device for withdrawing biological samples

The invention referres to a method for the preparation and selective replication of deoxyribonucleic acid (DNA) from biomaterial using PCR (polymerase chain reaction) for the analysis in time-of-flight mass spectrometers (TOF) with matrix-assisted laser desorption and ionization (MALDI) for determining specific genetic features in biomaterial. The invention consists, in a first step, of replicating the selected DNA segments by the PCR method in the usual unmodified fashion, and in a further enzymatic replication process, to replicate the DNA segments using modified substrates (the nucleic acids used for PCR) and specially prepared primers to such DNA analogs as are especially suitable for ionization by MALDI. Preparation of the primers particularly consists of introducing a charged group, which improves the ionization, and modification of the substrates is used to neutralize the negative charge on the phosphoric acid group of the DNA backbone. It is especially practical to immobilize the DNA on a surface for the fmal enzymatic reduplication process, for example on a prepared MALDI layer located on magnetic beads. In the final reduplication process, extremely little reagent is used, thus it is also possible in terms of low cost to use isotope-enriched material here in order to increase the mass resolving power.

Two-step method of DNA amplification for MALDI-TOF measurement

A method of analysing a nucleic acid by mass spectrometry comprising the steps of: (1) preparing a nucleic acid molecule comprising a negatively charged non-phosphate sugar-sugar linkage; (2) eliminating the charge from all, or up to all but ten, of the sugar-sugar linkages of the said nucleic acid molecule; (3) introducing the said nucleic acid molecule in which the charge has been wholly or partly eliminated as said into a mass spectrometer; and (4) determining the mass of the said nucleic acid molecule. Preferably, the nucleic acid has no or one charge. A method of preparing a nucleic acid molecule containing no or up to ten negative charges and no or up to ten positive charges comprising the steps of (1) synthesizing a nucleic acid with a phosphorothioate linkage or a phosphoroselenoate linkage between sugar residues, and (2) reacting the said nucleic acid with an alkylating agent so as to eliminate the charge on the said phosphorothioate linkage or said phosphoroselenoate linkage. The methods are useful for DNA sequencing and mutation analysis, and the nucleic acids are useful to suppress gene expression.

Method of nucleic acid analysis

Growing community of inventors

Berlin, Germany

Ivo Glynne Gut