The collection and preservation of biological material before DNA analysis is critical for inter alia biomedical research, medical diagnostics, forensics and biodiversity conservation. In this study, we evaluate an in-house formulated buffer called the Forensic DNA Laboratory-buffer (FDL-buffer) for preservation of biological material for long term at room temperature. Human saliva stored in the buffer for 8years, human blood stored for 3years and delicate animal tissues from the jellyfish Pelagia noctiluca comb jelly Beroe sp., stored for 4 and 6years respectively consistently produced high-quality DNA. FDL-buffer exhibited compatibility with standard organic, salting out and spin-column extraction methods, making it versatile and applicable to a wide range of applications, including automation.