A Smart Skin for Hydrogels That Enables Switchable Solute Release.
ACS Appl Mater Interfaces
; 16(7): 9201-9209, 2024 Feb 21.
Article
em En
| MEDLINE
| ID: mdl-38329464
ABSTRACT
Many applications of hydrogels rely on their ability to deliver encapsulated solutes, such as drugs; however, small hydrophilic solutes rapidly leak out of gels by diffusion. A need exists for a way to regulate solute release out of gelsâto ensure zero release until a desired time (the OFF state) and thereafter for the release to be switched ON at a high rate. This should ideally be a repeatable switch; i.e., the gel should be cyclable repeatedly between the ON and OFF states. Such perfect, cyclical ON-OFF release of solutes from gels is demonstrated for the first time through a "smart skin" that is synthesized rapidly (in â¼10 min) around an entire gel. The thin (â¼100 µm) and transparent polymer skin is endowed with redox-responsive properties through the use of urethane and acrylate monomers, one of which contains a thioether group. Initially, the skin is hydrophobic (water contact angle 102°), and it completely prevents hydrophilic solutes from leaking out of the gel. When contacted with oxidants such as hydrogen peroxide (H2O2), the thioethers are converted to sulfoxides, making the skin hydrophilic (water contact angle 42°) and thereby turning ON the release of solutes. Conversely, solute release can be turned OFF subsequently by adding a reducing agent such as vitamin C that reverts the sulfoxides to thioethers and thus returns the skin to its hydrophobic state. The release rate in the ON state can be tuned via the skin thickness as well as the oxidant concentration. The ability to regulate solute delivery from gels using smart skins is likely to prove significant in areas ranging from separations to agriculture and drug delivery.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Hidrogéis
/
Peróxido de Hidrogênio
Idioma:
En
Revista:
ACS Appl Mater Interfaces
Assunto da revista:
BIOTECNOLOGIA
/
ENGENHARIA BIOMEDICA
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
Estados Unidos
País de publicação:
Estados Unidos