Atherosclerotic cardio-cerebral vascular disease is the most common disease that threatens human health. Many researches indicated that oxidatively modified low-density lipoprotein (ox-LDL) is a key pathogenic factor of atherosclerosis. Here, we report the change of the secondary structure of ox-LDL caused by photoirradiation in an optofluidic resonator. The content ratios of amphipathic α-helices and β-sheets of ox-LDL are changed under laser beam illumination, resulting in an increasing binding rate of ox-LDL and ox-LDL antibodies. Our findings may provide a potential way for clinical atherosclerosis treatment and prompt recovery rate of atherosclerotic cardio-cerebral vascular disease by optical technology and immunotherapy.

A hollow-core metal-cladding waveguide (HCMW) optofluidic resonator that works based on a free-space coupling technique is designed. An HCMW can excite ultra-high-order modes (UOMs) at the coupled angle, which can be used as an optofluidic resonator to detect alterations of the epidermal growth factor receptor (EGFR) concentration. Theoretical analysis shows that the UOMs excited in the HCMW have a highly sensitive response to the refractive index (RI) variation of the guiding layer. An EGFR solution with a 0.2 ng/mL alteration is detected, and the RI variation caused by the concentration alteration is about 2.5×10 3.