Negatively-charged supported lipid bilayers regulate neuronal adhesion and outgrowth

Area of Science:

• Neuroscience
• Biomaterials Science
• Bioelectronics

Background:

• Achieving tight coupling between neuronal cells and electronic platforms is crucial for effective electrophysiological recording and stimulation in neuroelectronics.
• Supported lipid bilayers (SLBs) offer a biomimetic approach to improve cell-device integration by mimicking the cell's native plasma membrane.
• Modifying the surface charge of SLBs is a strategy to enhance electrostatic interactions and improve cell adhesion.

Purpose of the Study:

• To synthesize and characterize supported lipid bilayers (SLBs) with varying surface charges for interfacing with primary neurons.
• To investigate the effect of negatively charged SLBs on neuronal adhesion, neurite elongation, and network formation.
• To explore the potential of surface charge modulation as a tool to tune neuronal processes at the neuron-SLB interface.

Main Methods:

• Synthesis of SLBs with modified lipid compositions, including the addition of succinyl-PE to increase negative surface charge via phosphate groups.
• Further functionalization to introduce sulfonate groups, enhancing negative surface charge.
• Interfacing synthesized SLBs with primary neurons and evaluating neuronal adhesion, neurite outgrowth, and network formation.

Main Results:

• Negatively charged SLBs, despite expected electrostatic repulsion, demonstrated a positive influence on neurite elongation and branching.
• The study successfully created functionalized SLBs capable of interacting with neuronal cells.
• Neuronal network formation was observed on the modified SLB platforms.

Conclusions:

• Surface charge modification of SLBs can significantly influence neuronal morphology and network development.
• Negatively charged SLBs present a promising strategy for enhancing neuron-device interfaces in neuroelectronic applications.
• This work highlights the potential of tailoring biomimetic membranes to actively guide neuronal growth and function.