Closed-Perfusion Transretinal ERG Setup for Preclinical Drug and Nanostructure Testing

Area of Science:

• Neuroscience
• Pharmacology
• Biomedical Engineering

Background:

• The isolated mammalian retina is a potential biosensor for preclinical drug evaluation.
• Challenges exist in maintaining retinal viability for extended testing periods with limited perfusate.

Purpose of the Study:

• To develop a closed-perfusion transretinal electroretinography (tERG) setup for efficient preclinical drug testing.
• To enable testing with minimal drug molecules or nanostructures.

Main Methods:

• Ex vivo tERG was performed on mouse retinas (WT C57BL/6J).
• Retinas were perfused at 5-6 ml/min in a closed-circulation system requiring ~50 ml of perfusate.
• Rod and cone responses were assessed using light flashes, with Penicillin-Streptomycin used for long recordings.

Main Results:

• Rod responses remained stable for over 42 hours, and rod/cone bipolar cell responses for up to 12 hours.
• The setup was validated using IBMX (a PDE inhibitor).
• Tested materials, poly(sulfobetaine methacrylate) (PSMBA) and its monomer SBMA, showed no adverse effects on rod and bipolar cell function.

Conclusions:

• The developed closed-perfusion tERG setup facilitates extended experiments with minimal perfusate.
• This method is suitable for drug functionality, biocompatibility, and toxicity assessments of novel molecules and nanostructures.