Toxic heavy metals such as mercury have increased in concentration in the environment due to pollution. Inorganic mercury in the environment can be later converted to a more toxic form: methylmercury. Regular consumption of fish containing methylmercury can lead to several cognitive and motor disorders as well as Minamata disease. The current methods used to detect both methylmercury and inorganic mercury in sea life and drinking water involve long sample preparation and cost. In order to more efficiently track this toxic metal in the environment and identify contaminated food and water sources, a cheaper and faster method of detection is required. Fluorescent molecular sensors offer a more affordable alternative to current methods that would allow for detection and quantification of mercury in the environment. We report on fluorescent molecular sensors designed in our lab based on the organic compound thiophene, that have shown a selective response to mercury. The results show that thiophene containing compounds offer selectivity for mercury. Synthetic variations towards the design of effective sensors will be discussed.