# Tailoring the Design of Dendritic Thermogels Through Carbosilane and Polyglycerol Crosslinkers

## TL;DR

This study compares two types of dendritic crosslinkers in thermogels to improve control over their properties for biomedical applications like drug delivery.

## Contribution

A comparative analysis of carbosilane and polyglycerol dendrimers as crosslinkers in Pluronic L35 thermogels for biomedical applications.

## Key findings

- CBS hydrogels showed sustained doxorubicin release over one week due to network swelling.
- dPG hydrogels exhibited a burst release of doxorubicin within 4–24 hours due to strong interactions with the scaffold.
- Dendritic crosslinkers provided better control over swelling, mechanical properties, and degradation.

## Abstract

Background/Objectives: The development of stimuli-responsive hydrogels for biomedical uses is an intense field of research. The use of dendritic crosslinkers can enhance the control over the structure and properties of the networks. This work presents a comparative study on the design and evaluation of Pluronic L35 thermogels, incorporating either hydrophobic carbosilane dendrimers (CBS, generations 1 to 3) or hydrophilic dendritic polyglycerols (dPG, 10 k) as crosslinkers. Methods: The thermogels were synthesized via UV-initiated thiol–ene click chemistry. Additionally, they were characterized through swelling studies, mechanical properties, degradation kinetics as well as loading and release studies of the antitumor drug doxorubicin as poorly soluble model cargo. Results: The incorporation of dendritic crosslinkers allowed higher control over the crosslinking process, while the amphiphilic polymer imparted temperature-responsive properties to the resulting networks. Remarkable differences were observed in swelling behavior, mechanical properties and degradation kinetics, depending on the nature of the dendritic crosslinker. Additionally, regarding doxorubicin loading and release in water, CBS hydrogels produced a sustained release over one week, led by network swelling, while dPG hydrogels exhibited a burst release in 4–24 h but were limited by the stronger interaction of DOX with the dPG scaffold. Conclusions: The study provided useful insight for the tailoring of dendritic thermogels for specific biomedical uses such as controlled drug delivery.