Researchers from Ecole Polytechnique Fédérale de Lausanne in Switzerland have developed new nanoparticles for theranostic (therapeutic and diagnostic) applications. Their work describes the synthesis of these particles and demonstrates that by stimulating at a long, safe wavelength, the nanoparticles can cleave bonds that hold onto drugs and release them into the body. This is an exciting development for the field of nanomedicine, and may one day lead to improved detection and treatment of many diseases, including cancer.
Nanoparticles have been developed in the past for theranostic applications, but they tended to rely on UV light, which is potentially dangerous and does not penetrate far into the body. To overcome this, the researchers utilized a new class of nanoparticles, called “harmonic nanoparticles,” which are sensitive to UV as well as safer, longer wavelength light, such as red and near infrared.
The way the technology works is the near infrared light stimulates the harmonic nanoparticle, which produces light at shorter wavelengths. The shorter wavelength can then break photo-sensitive bonds, which keep drugs attached to the particle. When those bonds are broken, the drugs are released.
In a proof of concept study, the authors synthesized bismuth ferrite harmonic nanoparticles (BFO HNPs). The HNPs were stimulated with light at 790 nm wavelength, which resulted in a release of light at 395 nm. That light then caused at photosensitive bond to be cleaved, releasing a molecule from the nanoparticles. The team quantified nanoparticle release using ultrahigh-performance liquid chromatography-mass spectrometry (UHPLC-MS). They found that without near-infrared stimulation the drug was not released, but upon stimulation the drug was released over time, demonstrating the particle behaves as desired.
The authors state that “this work is an important step in the development of nanocarrier platforms allowing decoupled imaging in tissue depth and on-demand release of therapeutics.”
The publication in ACS Applied Materials and Interfaces: Two-photon triggered photorelease of caged compounds from multifunctional harmonic nanoparticles