Near-Infrared Light-Triggered Dissociation of Block Copolymer Micelles Using Upconverting Nanoparticles

Abstract

We demonstrate a novel strategy enabling the use of a continuous-wave diode near-infrared (NIR) laser to disrupt block copolymer (BCP) micelles and trigger the release of their "payloads". By encapsulating NaYF(4):TmYb upconverting nanoparticles (UCNPs) inside micelles of poly(ethylene oxide)-block-poly(4,5-dimethoxy-2-nitrobenzyl methacrylate) and exposing the micellar solution to 980 nm light, photons in the UV region are emitted by the UCNPs, which in turn are absorbed by o-nitrobenzyl groups on the micelle core-forming block, activating the photocleavage reaction and leading to the dissociation of BCP micelles and release of co-loaded hydrophobic species. Our strategy of using UCNPs as an internal UV or visible light source upon NIR light excitation represents a general and efficient method to circumvent the need for UV or visible light excitation that is a common drawback for light-responsive polymeric systems developed for potential biomedical applications.

One-Step Electrodeposition of Self-Assembled Colloidal Particles: A Novel Strategy for Biomedical Coating

“…A similar diameter-decreasing phenomenon has also been obtained in other coumarincontaining self-assembled systems. 45,46 It is believed that this photo-cross-linking property of the particles can also affect the properties of coating systems. As reported in previous work, 47 UV cross-linking of colloidal particles at the oil−water interface can make a dense shell of colloidosomes and lock the interfacial particles in a Pickering or Mickering emulsion.…”

Lanthanide‐Doped Upconversion Nanoparticles: Emerging Intelligent Light‐Activated Drug Delivery Systems

“…UV‐sensitive BCP comprising of hydrophilic poly (ethylene oxide) (PEO) and a hydrophobic polymethacrylate bearing photocleavable o ‐nitrobenzyl (PNBMA) groups which its absorption overlaps with the 350 nm anti‐Stokes emission from UCNPs under 980 nm illumination (5 W cm –2 , 4 h) ( Figure 5 ). 125 …”

Recent advances in the optimization and functionalization of upconversion nanomaterials for in vivo bioapplications

“…Branda and Zhao and coworkers 82 reported on an upconversion phototriggered micelle system composed of poly(ethylene oxide)-block-poly(4,5-dimethoxy-2-nitrobenzyl methacrylate) and NaYF 4 :Yb,Tm@NaYF 4 UCNPs. The mechanism behind this system involves UCNPs converting the 980 nm excitation radiation to UV upconversion emissions and transferring the energy to the onitrobenzyl group on the micelle core-forming block that induces a photo-cleavage reaction and destroys the micelle structure.…”