A hydrogel is a network of polymer chains that are hydrophilic, meaning they are attracted to water. They are often used as matrices for tissue engineering or drug delivery because they can mimic the extracellular matrix. Hydrogels are also being investigated for their potential use in nanotechnology.
Hydrogels are made up of cross-linked polymers. The degree of crosslinking determines the properties of the hydrogel. For example, more highly cross-linked hydrogels will be less permeable to molecules than those that are less cross-linked. The degree of crosslinking can also affect the mechanical properties of the hydrogel; more highly cross-linked gels will be stiffer and stronger than those that are less cross-linked.
Hydrogels can be synthesized from a variety of monomers including acrylamide, vinyl pyrrolidone, and ethylene glycol dimethacrylate. The choice of monomer will determine the properties of the resulting hydrogel. For example, acrylamide based gels are typically transparent while vinyl pyrrolidone based gels tend to be opaque.
Hydrogels have a number of applications in medicine and biotechnology. They have been used as contact lenses, wound dressings, and blood substitutes. Hydrogels can also be used to deliver drugs or other therapeutic agents directly to specific tissues or organs via implantation or injection. This targeted delivery allows for higher concentrations of the drug at the site where it is needed while minimizing side effects elsewhere in the body.
The unique combination of high water content and three dimensional structure makes hydrogels an ideal environment for cell culture studies. Cells grown on or within hydrogels retain many characteristics of cells grown in vivo including morphology, gene expression patterns, and responses to stimuli such as growth factors and cytokines . This has led to their use in a variety models ranging from simple 2D cultures to complex 3D organoids . In addition, because they closely resemble native tissue environments,hydrogELS ARE BEING INVESTIGATED FOR USE IN TISSUE ENGINEERING APPLICATIONS SUCH AS THE REPAIR OF DAMAGED OR DEGENERATING TISSUES .
While historically most research on hydogles has focused on their biomedical applications there is an increasing amount exploration into their potential use in nanotechnology . One area nanofabrication where they hold promise is self-assembly . Self-assembly is a process by which complex structures spontaneously form from simpler components following specific instructions encoded within them . Because they already exist in a preassembled state ,hydorgles could potentially provide a scaffold onto which other nano objects could be assembled leading to new methods for fabricating devices with desired functions .