In silico investigation of BC₅₉ nanocage for furan adsorption and single-use detection potential

Furan is a hazardous environmental and food-processing contaminant for which rapid and accessible detection methods are needed. In this theoretical density functional theory study, pristine C₆₀ and its B- and N-substituted derivatives, BC₅₉ and NC₅₉, were evaluated as candidate materials for furan adsorption and sensing-related applications using the B97D and ωB97X-D functionals. The two functionals produced consistent qualitative rankings for the calculated properties, with Pearson correlation coefficients greater than 0.97 and Spearman coefficients of 1.00. Among the investigated systems, BC₅₉ exhibited the strongest calculated adsorption, with adsorption energies ranging from -34.61 to -49.44 kcal.mol^-1, together with the largest adsorption-induced conductivity change and a pronounced reduction in the HOMO-LUMO energy gap. NBO analysis indicated stronger donor-acceptor stabilization in BC₅₉@Furan, with E⁽²⁾ values of up to 61.81 kcal.mol^-1. QTAIM, NCI, RDG, ELF, and LOL analyses also suggested a stronger and more localized interaction at the BC₅₉@furan interface than in the C₆₀@Furan and NC₅₉@Furan complexes. However, the exceptionally long predicted desorption times indicate that BC₅₉ would not be suitable for rapidly reusable sensing applications at room temperature. Instead, it may be considered a candidate permanent adsorbent or a theoretically proposed single-use detection platform. These computational predictions represent a pre-synthesis screening step and require experimental validation before practical application.