Biomedical researchers at Binghamton
University in the USA, have developed a mechanism for drug-carrying liposomes
that can be activated in the eye using near-infrared light.
The remotely triggered on-demand liposomal
delivery system has been studied to treat glaucomatous neurodegeneration in
mice.
The researchers overcame some difficulties
in their drug delivery mechanism. “The first problem we found is that most
pharmacological compounds are hydrophobic, which means they have low water
solubility,” Wang said. “The second problem is using a thermal effect to
trigger the release — how do we do that without affecting a patient’s comfort
or having side effects?”
The scientists utilized the localized
surface plasmon resonance (LSPR) effect of gold nanorods (AuNRs) under
near-infrared (NIR) light (808 nm) to control the release of
cyclodextrin-encapsulated melatonin from thermally responsive liposomal
nanocarriers in the vitreous humor.
The liposomes—which are small, spherical,
artificial vesicles that can deliver drugs and other molecules to specific
sites in the body—have the gold nanorods embedded on their fatty surface. The
gold heats up under a specific near-infrared wavelength and breaks down the
membrane to release the needed medication, which is mixed with cyclodextrin to
aid its absorption into the eye.
By enhancing the drug's solubility and
stability through cyclodextrin encapsulation, this remotely activated
melatonin/HPβCD AuNRs liposomes delivery system can decrease intraocular
pressure (IOP) elevation by (24 ± 7)%, enhance the survival rate of RGCs by (77
± 6)%, and decrease glial fibrillary acidic protein (GFAP) activation by (75 ±
6)% at depth in an acute experimental glaucoma model.
This NIR-triggered drug delivery system
presents the potential of a promising minimally photo-triggered therapeutic
option for glaucoma treatment.
The scientists call it a minimally-invasive
procedure, as they claim that the patient will need only a one-time injection
that will be sufficient to lower the IOP.
REFERENCE:
Matuwana D, Hong
E, Huang S, Xu X, Jang G, Xiao R, Rao S, Wang Q. Near-infrared activated
liposomes for neuroprotection in glaucoma. J Mater Chem B. 2024 Oct
30;12(42):10902-10914. doi: 10.1039/d4tb00745j. PMID: 39355895.
