# Self-Assembled Hydrogel from Pyrene-Modified Peptide as 3D Matrices for Neuronal Cell

## TL;DR

A new pyrene-modified peptide forms stable hydrogels that support neuronal cell growth in 3D culture.

## Contribution

A novel pyrene-modified peptide, Py-L3K3, is shown to form stable and functional hydrogels suitable for neuronal cell culture.

## Key findings

- Py-L3K3 forms stable fluorescent hydrogels at both neutral and basic pH.
- Py-L3K3 hydrogels support neuronal cell viability, attachment, and growth under physiological conditions.
- Molecular dynamics simulations indicate pH-dependent clustering drives hydrogel formation.

## Abstract

Self-assembled hydrogels offer biomimetic platforms for
three-dimensional
(3D) cell culture; yet, achieving stability and functionality under
physiological conditions remains a challenge. Here, we report a series
of pyrene (Py)-modified peptides designed to form hydrogels with tunable
physical and biological properties. Among them, Py-L3K3 uniquely formed stable, fluorescent hydrogels at both neutral
and basic pH, in contrast to Py-K6 and Py-A3K3, which gelled only at basic pH. Molecular dynamics
simulations revealed pH-dependent clustering as a key mechanism driving
hydrogel formation. Structural analysis showed that Py-L3K3 forms nanofibrillar networks with granular surface
morphologies and β-sheet-rich conformations. Rheological studies
demonstrated its solid-like viscoelastic behavior and self-healing
capability, as determined by oscillatory shear measurements. Importantly,
Py-L3K3 supported neuronal cell viability, attachment,
and growth under physiological conditions, highlighting its potential
as a 3D culture scaffold. These findings present Py-L3K3 as a promising candidate for applications in neuronal engineering
and injectable regenerative biomaterials.