Determining an unknown quantity of target molecule species, comprises contacting the target molecules with a defined quantity of reporter group-free aptamer molecules

摘要

Determining an unknown quantity of target molecules comprising contacting the target molecules with a defined quantity of reporter group-free aptamer molecules, is new. The aptamer molecules form aptamer/target molecule complexes with the target molecules, and/or are determined quantitatively in aptamer-target molecule-complexes. Determining an unknown quantity of target molecules comprising contacting the target molecules with a defined quantity of reporter group-free aptamer molecules, is new. Quantitative determination of aptamer molecules is effected using a quantitative amplification process, especially real-time PCR. A system containing a defined quantity of marked target molecules of the target molecule species, and an unknown quantity of non-marked target molecules of the same target molecule species, is contacted with a defined quantity of aptamer molecules specific to the target molecule species. Through binding of the aptamer molecules to the target molecules, aptamer/non-marked target molecule complexes, and aptamer/marked target molecule complexes are formed. A distribution is set up between the quantity of non-bound aptamer molecules, aptamer/non-marked target molecule complexes and aptamer/marked target molecule-complexes. The aptamer/marked target molecule complexes are separated from non-bound aptamer molecules and aptamer/non-marked target molecule-complexes. The quantity of non-bound aptamer molecules is determined quantitatively and/or the aptamer/marked target molecule complexes are dissociated and the quantity of aptamer molecules released from the complexes is quantitatively determined. Values obtained, are input into a standard curve. This is obtained through repeated execution of the foregoing stages under the same conditions, but using different defined quantities of target molecules. By input of the values obtained into the standard curve, the unknown quantity of non-marked target molecules is obtained. The aptamer/target molecule-complexes, marked and/or non-marked, are separated from non-bound aptamer molecules using molecular weight-specific, separation processes. Marking of the target molecules is selected from: binding to a solid phase, especially to an immobile solid phase or to mobile particles, binding to an anchor group for immobilization onto a solid phase, or binding to a selection group for a physical and/or physical-chemical separation process. An independent claim is included for the corresponding test system.