Abstract: The present invention relates to the field of improving and stabilizing concentrated solutions and in particular to improving and stabilizing concentrated solutions for the extraction of nucleic acids from sample material. Thus, the present invention, further, relates to the field of molecular biology. The present invention describes the use of betaines for stabilizing organic salts or chaotropic agents in solution which is particularly useful in cases where organic salts or chaotropic agents are present at high concentration such as for example chaotropic agents in buffers for the extraction of nucleic acids from sample material. The present invention describes the corresponding buffers and further relates to processes for the extraction of nucleic acids from sample material as well as processes for the analysis of sample material. Moreover, the present invention relates to kits and cartridges comprising at least one container with the corresponding buffer.