Temperature and pH dual responsive 2-(dimethylamino)ethanethiol modified starch derivatives via a thiol-yne reaction for drug delivery
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In this study, a novel type of temperature/pH dual responsive polymer PyHES- DMAET ((2-hydroxy-3-(2-propynyloxy) propyl hydroxyethyl starch (PyHES))-2-(dimethylamino) ethanethiol (DMAET)) was synthesized. First, the temperature-responsive polymer PyHES was prepared via hydrophobic modification of hydroxyl groups in hydroxyethyl starch (HES) with propynylglycidyl ether (PGE) subsequently; pH-responsive tertiary amine group was connected to the propynyl group via a thiol-yne click reaction. Because PyHES-DMAET has pH-responsive amino groups and hydrophobic thioether groups, its aqueous solution exhibits excellent temperature/pH dual sensitivity, i.e., a good transference between the hydrophobic (or self-assembly) and hydrophilic (or swelling) state along as a result of changing temperature/pH values; these properties can be exploited, for hydrophobic drug release. The drug release reached 96% at 37 °C and a pH of 6.5. The drug loading capacity of PyHES-DMAET was increased by increasing the degree of substitution (DS) of the hydrophobic propynyl groups in the PyHES. The highest drug loading capacity for doxorubicin (DOX) achieved in this study was 33 wt%.
KeywordsHydroxyethyl starch 2-(dimethylamino)ethanethiol Temperature/pH dual responsive Drug release Thiol-yne reaction
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Conflict of interest
The authors declare that they have no competing interests.
- 4.Bogomolova A, Kaberov L, Sedlacek O, Filippov SK, Stepanek P, Král V, Wang XY, Liu SL, Ye XD, Hruby M (2016) Double stimuli-responsive polymer systems: how to use crosstalk between pH- and thermosensitivity for drug depots. Eur Polym J 84:54–64. https://doi.org/10.1016/j.eurpolymj.2016.09.010 CrossRefGoogle Scholar
- 6.Eggers S, Lauterbach F, Abetz V (2016) Synthesis and self-assembly of high molecular weight polystyrene-block-poly[2-(N-morpholino)ethyl methacrylate]: a story about microphase separation, amphiphilicity, and stimuli-responsivity. Polymer 107:357–367. https://doi.org/10.1016/j.polymer.2016.04.066 CrossRefGoogle Scholar
- 14.Bai Y, Zhang Z, Zhang A, Chen L, He C, Zhuang X, Chen X (2012) Novel thermo- and pH-responsive hydroxypropyl cellulose- and poly (l-glutamicacid)-based microgels for oral insulin controlled release. Carbohydr Polym 89(4):1207–1121. https://doi.org/10.1016/j.carbpol.2012.03.095 CrossRefGoogle Scholar
- 19.Carreira AS, Gonçalves FAMM, Mendonça PV, Gil MH, Coelho JFJ (2010) Temperature and pH responsive polymers based on chitosan: applications and new graft copolymerization strategies based on living radical polymerization. Carbohydr Polym 80(3):618–630. https://doi.org/10.1016/j.carbpol.2009.12.047 CrossRefGoogle Scholar
- 24.Wang Y, Heinze T, Zhang K (2016) Stimuli-responsive nanoparticles from ionic cellulose derivatives. Nano 8:648–657Google Scholar