هیدروژل‌­های پاسخگو به دما: مواد، سازوکارها و کاربردهای زیستی

نوع مقاله: پژوهشی

نویسندگان

تهران، پژوهشگاه پلیمر و پتروشیمی ایران، صندوق پستی 112- 14975

چکیده

در چند دهه اخیر، توجه بسیاری به کاربردهای دارویی و زیست‌­پزشکی پلیمرهایی جلب شده است که محلول­ آبی آن‌ها بتواند در پاسخ به محرک­‌های حاصل از تغییر شرایط محیطی درجا، هیدروژل تشکیل ­دهد. از این میان، محلول‌های پلیمری ژل­‌شونده در اثر دما به ­دلیل سادگی، کاربردی‌بودن و فراوانی نسبی سامانه‌­های پلیمری (طبیعی و سنتزی) ژل‌شونده در پاسخ به تغییر دما بیشتر بررسی و گزارش شده­‌اند. برخلاف هیدروژل‌های مرسوم، هیدروژل­‌هایی که در اثر محرک دما درجا تشکیل می­­‌شوند، در شرایط فیزیولوژی امکان تشکیل دارند و می‌­توانند یکپارچگی توده خود را در دوره زمانی معین حفظ ­کنند. کاربرد چنین موادی توسعه فرمول‌بندی‌­های دارویی با اختلاط محلول پلیمر و دارو را ساده­‌تر می‌­کند و می‌­توان با استفاده از آن‌­ها انحلال داروهای آب‌گریز با وزن مولکولی کم را بهبود داد. به علت آسانی فرمول‌بندی محصولات دارویی با انجام فرایند ساده اختلاط دارو(ها) با این مواد، زیست­‌سازگاری و امکان کاربردهای فراوان می‌­توان از آن‌­ها در زمینه‌­های پزشکی و دارویی با هدف مهندسی بافت، انحلال داروهای کم‌محلول و رهایش کنترل­‌شده داروها و درشت‌مولکول­‌های زیستی مانند پروتئین­‌ها و ژن‌­ها بهره برد. در این مقاله، هیدروژل‌های حساس به دما به لحاظ طبقه‌‌بندی، کاربرد و ترمودینامیک تشکیل مطالعه شده­‌اند. افزون بر این، سازوکار پاسخگویی هیدروژل‌­ها به دما، پلیمرهای ژل‌شونده، پیشرفت‌­های اخیر در طراحی مولکولی، سطوح و هیدروژل و نیز کاربردهای زیستی آن‌­ها بررسی شده است. همچنین، مطالعات اخیر در زمینه میسل‌ها و مزدوج­‌های زیستی هوشمند مرور شده است. در نهایت، محدودیت­‌ها و قابلیت‌­های کاربرد هیدروژل‌­های حساس به دمای تشکیل‌شونده درجا گزارش شده است. اطلاعات گزارش شده در این مقاله برای طراحی و توسعه سامانه­‌های ژلی پاسخگو به دما با کاربرد و خواص مختلف ضروری است.

کلیدواژه‌ها


عنوان مقاله [English]

Temperature-Responsive Hydrogels: Materials, Mechanisms and Biological Applications

نویسندگان [English]

  • Roghayyeh Marefat Seyedlar
  • Mohammad Imani
  • Mohammad Atai
  • Azizollah Nodehi
Iran Polymer and Petrochemical Institute, P.O. Box: 14975-112, Tehran, Iran
چکیده [English]

During the last decades, an increasing attention has been paid to pharmaceutical and biomedical applications of queous polymeric solutions which respond in accordance to the changes in their environmental conditions i.e., stimuli by turning into in situ forming hydrogels. Of all the stimuli-responsive hydrogels, temperature-responsive solutions have been widely investigated due to their simplicity, applicability and relatively high frequency of temperature-responsiveness, in situ gelling polymeric (natural or synthetic) systems. In contrast with the conventional hydrogels, in situ forming temperature-responsive hydrogels can form under physiological conditions and preserve their morphological integrity for a definite time course. Using the materials makes it easier to formulate pharmaceutical formulations by mixing polymer and drug, and also improve the dissolution of hydrophobic drugs with low molecular weight. Due to the simplicity of the pharmaceutical formulation by simple solution mixing, biocompatibility and convenient usage these materials can be used in biomedical and pharmaceutical fields for tissue engineering, solubilizing of sparingly soluble drug molecules, controlled delivery of drugs and biomacromolecules, such as proteins and genes. In this review, temperature-responsive hydrogels are studied regarding their classification, applications and thermodynamics. Moreover, temperature-responsiveness mechanisms, polymeric gels, recent advances in surface, hydrogel and molecular design and biomedical application are investigated. Also, this review focuses on recent investigation based on the designs of temperature-responsive micelles and intelligent bioconjugates. Finally, limitations and potentials of applications of the temperature-responsive in situ forming hydrogels have been reported. The reported information in this paper are necessary to design and develop a desirable temperature-responsive hydrogels with different characteristics and applications.

کلیدواژه‌ها [English]

  • reversible hydrogels
  • in situ gelling
  • critical solution temperature
  • sol-gel transition
  • aqueous polymeric solution
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