Abstract
Stimuli-responsive polymers have attracted significant interest in the fields of advanced materials and biomaterials. Herein, temperature- and pH-responsive glycopolymers, which are composed of N-isopropylacrylamide, methacrylic acid, and an acrylamide derivative bearing a lactose moiety, were synthesized via radical copolymerization. The series of resulting glycopolymers had different degrees of substitution of the lactose moieties, were responsive to temperatures between 26.6 °C and 47.6 °C, and formed aggregates above the lower critical solution temperature limit in mild acidic aqueous media (pH 4–6). The temperature-responsive behavior was dependent on the prevailing pH conditions, as no aggregation was observed in neutral and basic aqueous media (pH > 7). The aggregates had saccharide moieties on the surface in aqueous media. The number of saccharide moieties on the surface depended on the saccharide-containing unit ratio in the glycopolymer. The ratio was determined via enzymatic hydrolysis of the lactose moieties using β-galactosidase and the subsequent detection of the released galactose.
Highlights
Stimuli-responsive polymers, such as temperature, pH, ion, photo, and magnetic field-responsive polymers, have recently attracted significant interest for their use as films, gels, and vesicles for advanced materials and biomaterial applications [1,2,3,4,5]
NIPAM was used after recrystallization from n-hexane. 2-(Benzylsulfanylthiocarbonylsulfanyl) ethanol (BTSE) [31] and the Lac-bearing acrylamide derivative (LacAAm) [26] were synthesized according to previously published methods. β-Galactosidase from Aspergillus oryzae and the galactose assay kit were purchased from Sigma-Aldrich Co., LLC (MO, USA)
The synthetic route for the glycopolymers composed of NIPAM, methacrylic acid (MAA), and LacAAm is shown in Scheme 1
Summary
Stimuli-responsive polymers, such as temperature-, pH-, ion-, photo-, and magnetic field-responsive polymers, have recently attracted significant interest for their use as films, gels, and vesicles for advanced materials and biomaterial applications [1,2,3,4,5]. PNIPAM aqueous solutions become opaque when the surrounding temperature is above the LCST. This is because dehydration and aggregation processes prevail under these conditions. PH-responsive polymers, such as carboxylic acid group-containing polymers, are popular stimuli-responsive polymers that are of interest to researchers as they are useful for biomedical applications.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
