Member Profile

Dr. Salvatore Marras co-developed molecular beacons, one of the first fluorescent nucleic acid hybridization probe technologies. These probes are used for the real-time monitoring of nucleic acid amplification assays, such as polymerase chain reactions (PCR) and isothermal nucleic acid amplification assays, such as the nucleic acid sequence-based amplification (NASBA) and loop-mediated isothermal amplification (LAMP) assays. Real-time amplification enables the detection and quantitative measurement of rare DNA and RNA targets in clinical samples. Furthermore, these assays can be carried out in sealed reaction tubes, thereby preventing the contamination of untested samples. Since fluorescent nucleic acid hybridization probes remain dark when not hybridized to a target sequence, they also enable the detection of DNA and RNA targets in living cells. His research focuses on the different properties of fluorescent hybridization probes, such as design parameters that affect their specificity, and on the effects of interactions between different fluorophore & quencher pairs. His group also develops novel nucleic acid detection methods, including: self-reporting DNA microarray platforms; highly multiplexed, real-time nucleic acid amplification assays for the detection of infectious agents in clinical samples; and extremely sensitive in situ and in vivo hybridization methods, utilizing organic-based fluorescent reporters and metal-based luminescent compounds. More recently, he co-invented the SuperSelective primer technology, which enables the detection and quantitation of somatic mutations, whose presence relates to cancer diagnosis, prognosis, and therapy, in real-time multiplex PCR assays that can potentially analyze rare DNA fragments present in blood samples (liquid biopsies). However, SuperSelective primer applications are not limited to cancer diagnosis as they can be used to identify and quantify any rare mutant DNA fragment in a large background of wild-type DNA fragments, such as multi-drug resistant bacteria and fungi.