Mable C J, Fielding L A, Derry M J, Mykhaylyk O O, Chambon P, Armes S P
Department of Chemistry , Uni. of Sheffield , Dainton Building, Brook Hill , Sheffield , South Yorkshire S3 7HF , UK . Email:
School of Materials , Uni. of Manchester , Oxford Rd , Manchester , M13 9PL , UK.
Chem Sci. 2017 Dec 13;9(6):1454-1463. doi: 10.1039/c7sc04788f. eCollection 2018 Feb 14.
A series of pH-responsive all-methacrylic ABC triblock copolymer vesicles were prepared from precursor diblock copolymer vesicles RAFT seeded emulsion polymerisation. Microphase separation between the two hydrophobic membrane-forming B and C blocks produced a distinctive framboidal morphology, for which the mean globule size can be tuned by adjusting the triblock copolymer composition. These vesicles remain intact at neutral pH, but undergo irreversible dissociation on addition of acid as a result of protonation of the tertiary amine groups located within the third block. Small-angle X-ray scattering (SAXS) was utilised to characterise the morphologies formed at pH 8 and pH 3. According to time-resolved SAXS studies, the acid-induced dissociation of these pH-responsive framboidal vesicles involves appreciable membrane swelling within 50 ms and is complete.
通过可逆加成-断裂链转移（RAFT）种子乳液聚合，从前驱体二嵌段共聚物囊泡制备了一系列pH响应性全甲基丙烯酸ABC三嵌段共聚物囊泡。两个形成疏水膜的B和C嵌段之间的微相分离产生了独特的莓球状形态，其平均球粒尺寸可通过调节三嵌段共聚物组成来调整。这些囊泡在中性pH下保持完整，但由于第三嵌段内叔胺基团的质子化，加入酸后会发生不可逆解离。利用小角X射线散射（SAXS）表征在pH 8和pH 3下形成的形态。根据时间分辨SAXS研究，这些pH响应性莓球状囊泡的酸诱导解离在50毫秒内涉及明显的膜膨胀，并且是完全的。
