ABSTRACT Laser trapping provides a powerful noncontact approach for manipulating biomolecules and probing protein aggregation processes with high spatial precision. In this study, we demonstrate near‐infrared (NIR) laser trapping‐induced amyloid fibril formation from hen egg white lysozyme (HEWL) under acidic conditions (pH H 2). A 10 mg/mL of HEWL solution in 0.1% HCl was irradiated with an 800 nm continuous‐wave laser at 600 mW for 30 min. Thioflavin T (ThT) fluorescence exhibited a pronounced intensity enhancement and characteristic green emission, confirming the formation of β‐sheet‐rich amyloid structures. Simultaneously, increased light scattering of the trapping laser indicated protein aggregation. Photoluminescence lifetime measurements revealed a transition from sub‐nanosecond to several‐nanosecond lifetimes, further supporting amyloid formation. Transmission microscopy showed ordered fibrillar assemblies following irradiation. These findings highlight the synergistic role of acidic conditions and optical trapping in accelerating amyloid formation, providing a tunable platform to study protein misfolding relevant to neurodegenerative diseases.
Islam et al. (2026) studied this question.