Fluorescent nanodiamond - hyaluronate conjugates for target-specific molecular imaging

Area of Science:

• Nanotechnology
• Biomedical Imaging
• Materials Science

Background:

• Current molecular imaging agents face limitations in signal-to-background ratio, brightness, photostability, and biocompatibility.
• Fluorescent nanodiamonds (FNDs) offer potential as photostable and biocompatible imaging materials due to their bright red light emission from nitrogen vacancy (NV) centers.

Purpose of the Study:

• To evaluate the feasibility of using FNDs conjugated to hyaluronate (HA) for targeted molecular imaging.
• To assess the biocompatibility, target-specific delivery, and in vivo imaging capabilities of HA-FND conjugates.

Main Methods:

• Conjugation of FNDs with hyaluronate (HA) to create HA-FND conjugates.
• In vitro cell viability and competitive cellular uptake tests using HepG2 cells.
• In vivo fluorescence lifetime (FLT) assessment, in vivo imaging system (IVIS) analysis, and ex vivo biodistribution tests.
• Renal clearance and histological analyses for safety evaluation.

Main Results:

• HA-FND conjugates demonstrated excellent biocompatibility and target-specific intracellular delivery to HepG2 cells.
• In vivo imaging confirmed the liver-targeted delivery of HA-FND conjugates with statistically significant results.
• Renal clearance and histological analyses supported the in vivo biocompatibility and safety of the HA-FND conjugates.

Conclusions:

• HA-FND conjugates are feasible and promising photostable, biocompatible materials for molecular imaging applications.
• The study highlights the potential of FNDs for enhancing molecular imaging by overcoming current limitations.