2.3. Time-Resolved Fluorescence

Fluorescence lifetime measurements were performed using a Mini-tau filter-based fluorescence lifetime spectrometer coupled to a Time-Correlated Single Photon Counting (TCSPC) system (Edinburgh Instruments, Livingston, UK). Aliquots of piperine were added in the IL-1β solution at 10 μM. Piperine concentration varied from 0 to 49 μM. Experiments were carried out at 298 K.

The sample was excited at 295 nm using a picosecond pulsed light emitting diode (LED), and fluorescence decay was collected using a 340 nm filter. The fluorescence decay profile (Figure S2) was fitted using multiexponential decay (Equation (3)), where τ_i is the lifetime of each component, and α_i is the contribution of each component to total fluorescence decay. The average lifetime <τ_avg> was calculated using Equation (4) (Table S1).