Detecting and monitoring of low amounts of DNA is crucial for many biomedical and forensic applications. Improving detection sensitivity becomes then a central goal of DNA-based testing and diagnostics. In this thesis, we look at three approaches (steady state emission, fluorescence lifetime, and advanced multipulse detection) that demonstrates the potential for significant sensitivity enhancement for detecting small amounts of DNA. These methods are straightforward and are used in accompaniment with spectral decomposition using a standard DNA intercalator: Ethidium Bromide (EtBr). The developed techniques can be applied to various other intercalators and ultimately in practical applications. This will allow for better decision-making in clinical medicine, biological and environmental research, and human identification in forensic investigations.