Metal-Organic Frameworks in Surface Enhanced Raman Spectroscopy - based Analysis of Volatile Organic Compounds

Volatile Organic Compounds (VOCs) represent health and environmental hazardous compounds but also play crucial roles in other fields including early disease diagnostics and organoleptic perception of aliments important in food production. Accurate VOCs analysis is essential, and require innovative analytical methods for rapid on-site detection without complex sample preparation. Surface-enhanced Raman spectroscopy (SERS) is a versatile analytical platform ideal for detecting chemical species. It relies on optical probing metallic nanostructures endowing tightly confined electromagnetic fields associated with resonant coupling to surface plasmons, then boosting the efficiency of Raman scattering to sensitivity at even single molecule detection. Nonetheless, SERS faces limitations, especially analytes that do not bond with noble metals. This limitation can be circumvented by interfacing the sensor surface with Metal-Organic Frameworks (MOFs). Known for their chemical and structural versatility, MOFs efficiently pre-concentrate low molecular weight species in their porous structure. This review presents recent developments in MOF-based SERS substrates emphasizing design rules for maximizing analytical performance. An overview of the status of the detection of harmful VOC is discussed in the context of industrial and environmental monitoring. In addition, a survey of VOC analysis for medical diagnosis and emerging applications in aroma and flavor profiling is included.