Optically Modulated Theranostic Nanoparticles

Abstract

Nanoparticles are rapidly advancing as drug carriers for directing therapies in a spatio-temporally controlled manner. By virtue of their size ranging from tens to hundreds of nanometers, nanoparticles can preferentially trap in tumors and aberrant vascular interstitium, and can be targeted to specific molecular pathologies. Theranostic nanoparticles is an umbrella term designating the carriers, which combine both the drug/therapy transport with an imaging contrast. With suitable targeting, theranostic nanoparticles can be used for molecular imaging, and potentially for monitoring therapy response.1 To enhance therapy specificity to the disease site and reduce off-target effects, external and direct spatial-temporal control on therapy delivery is desirable. 2Multiple approaches for modulating theranostic nanoparticles have been reported, viz. magnetic fields, sonic energy, and optical radiation. Optical modulation in the range of visible and near infrared (NIR) wavelengths is a valuable tool for theranostic nanoparticle modulation because of its non-ionizing and safe nature, tissue penetration of multiple centimeters, easy multiplexing by including multiple interrogation wavelengths/ multiple fluorophores, low-cost, and advances in miniaturization of