Skip to main content
. 2021 Jul 17;13(7):499. doi: 10.3390/toxins13070499

Figure 1.

Figure 1

Operating principles of label-free optical immunosensors. (A) Surface plasmon resonance (SPR); (B) optical waveguide lightmode spectroscopy (OWLS); (C) planar waveguide; (D) white light reflectance spectroscopy.