Poloxamer Hydrogels for Biomedical Applications

Abstract

This review article focuses on thermoresponsive hydrogels consisting of poloxamers which are of high interest for biomedical application especially in drug delivery for ophthalmic, injectable, transdermal, and vaginal administration. These hydrogels remain fluid at room temperature but become more viscous gel once they are exposed to body temperature. In this way, the gelling system remains at the topical level for a long time and the drug release is controlled and prolonged. Poloxamers are synthetic triblock copolymers of poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) (PEO-PPO-PEO), also commercially known as Pluronics®, Synperonics® or Lutrol®. The different poloxamers cover a range of liquids, pastes, and solids, with molecular weights and ethylene oxide–propylene oxide weight ratios varying from 1100 to 14,000 and 1:9 to 8:2, respectively. Concentrated aqueous solutions of poloxamers form thermoreversible gels. In recent years this type of gel has arouse interest for tissue engineering. Finally, the use of poloxamers as biosurfactants is evaluated since they are able to form micelles in an aqueous environment above a concentration threshold known as critical micelle concentration (CMC). This property is exploited for drug delivery and different therapeutic applications.

Pharmacotechnical Development of a Nasal Drug Delivery Composite Nanosystem Intended for Alzheimer’s Disease Treatment

“…Poloxamers are biodegradable by erosion [57] and biocompatible polymers [58]. Based on these safety data and the information that the manufacturing process can be controlled to limit unwanted impurities, the Cosmetic Ingredient Review Expert Panel concluded that poloxamers are safe as used [59].…”

A convenient approach by using poly‐(HEMA‐co‐NIPAM)/Cu2+ solution sol–gel transition for wound protection and healing

“…Temperature‐responsive hydrogels can respond to external temperature stimuli and alter their structural or other properties depending upon environmental changes; thus, these materials are vastly promising for various applications, such as controlled drug delivery, sensors, and tissue engineering (Russo & Villa, 2019). In addition, temperature‐responsive hydrogels are suitable for biological applications because they can generate a remarkably rapid response to biological temperatures, they are convenient and quick, and they cause minimal damage to biological specimens and living tissues (Klouda, 2015).…”

Chitosan and its Derivatives for Ocular Delivery Formulations: Recent Advances and Developments

“…Poloxamers or Pluronics ® are a class of water-soluble, non-ionic, triblock copolymers, composed of a central poly(propylene oxide) (PPO) block and two terminal poly(ethylene oxide) blocks [181]. A wide range of poloxamers is commercially available with varying block molecular weights.…”

“…Poloxamers can form thermoreversible gels in aqueous solutions, generally around 37 • C, and they have attracted growing interest as carriers for bioactive compounds and other biomedical applications [181]. Nevertheless, the poor mechanical properties are a major drawback of pure poloxamer gels.…”