Langmuir–Blodgett films of porphyrins and phthalocyanines as chemical sensors

This chapter investigates the application of Langmuir-Blodgett (LB) films based on porphyrins and phthalocyanines for chemical sensing. Due to their thermal, mechanical, and photochemical stability, these tetrapyrrolic compounds are ideal for sensor devices, with properties tunable through central metal substitution or peripheral functionalization. Among transduction techniques, quartz crystal microbalance (QCM) is widely employed to monitor mass variations resulting from interactions between active films and analytes, proving especially effective for volatile organic compounds (VOCs). Spectroscopic approaches such as UV-Vis and SPR highlight the versatility of porphyrins in detecting analytes via optical and conformational interactions. Additionally, electrochemical and biosensor methodologies are described for detecting biologically relevant molecules, such as phenols and catecholamines. The unique properties of LB and LS films offer promising perspectives for advanced chemical sensors and biosensor devices.