For characterization, Fourier Transform Infrared Spectroscopy (FTIR) analysis was performed using an ATR-FTIR (Agilent Cary 630 FTIR) instrument following calibration procedures. The instrument parameters included a sample scan of 30 and a background scan of 16, operating over a range from 4000 cm⁻¹ to 650 cm⁻¹ with a resolution set at 8. After placing a small amount of the sample onto the ATR crystal surface and ensuring direct contact, infrared spectra were collected. This method enabled the identification of functional groups within the P. longifolia extract and the synthesized nanoparticles, respectively .