A new, fast, simple and cost-effective sensing device for monitoring H(2)S has been developed. Proof-of-principle results showing that a commercial and cheap Myoglobin (Mb) can be successfully used as a biological probe for a fluorescence biosensor for H(2)S detection are reported. The two different commercial labels Cy3 and Atto620 were selected for this study. A high selectivity for detecting H(2)S against other thiols was found. The applicability of the proposed sensing system was successfully explored not only in solution but also when applied in the form of a solid state device.