• Development of a Cu-MOF hydrogel RLS sensor for vancomycin detection in EBC • Achievement of good sensitivity with a 0.05–2.3 μg·mL -1 linear range and 0.009 μg·mL -1 detection limit. • Successful application to patient samples demonstrating repeatability and selectivity for clinical use. In this study, a Rayleigh light scattering (RLS) sensing platform was developed based on a copper- benzene-1,3,5-tricarboxylic acid metal–organic framework integrated into an agarose hydrogel matrix (Cu-MOF hydrogel) for the quantification of vancomycin in exhaled breath condensate (EBC). The interaction of vancomycin with the Cu-MOF hydrogel induced measurable changes in the RLS intensity, enabling a sensitive and straightforward analytical response. Under the optimized conditions, the method exhibited a linear response to vancomycin within the range of 0.05-2.3 μg.mL -1 and a low limit of detection of 0.009 μg.mL -1 . The probe demonstrated good repeatability (RSD <2.9) and acceptable selectivity in the presence of common co-administered drugs. Finally, the developed method was successfully applied to patient’s EBC samples, confirming its potential for non-invasive determination of vancomycin exposure using a rapid, and low-cost analytical strategy.
Behboudi et al. (2026) studied this question.