A study of the complex interaction between poly allylamine hydrochloride and negatively charged poly(N-isopropylacrylamide-co-methacrylic acid) microgels

Abstract

We studied the complex interaction between polyNIPAm-based microgels and a positively charged polyelectrolyte. Also, the microgels were loaded with doxorubicin and its release was evaluated as a function of the polyelectrolyte molecular weight.

Thermodynamic Theory of Multiresponsive Microgel Swelling

“…We consider microgels with N seg = 10 7 segments and n ch = 50, 100, and 200, having either x MAA = 0.1, 0.35, or 0.5. Our goal is to evaluate the effect of increasing or reducing the amount of the acidic monomer with respect to poly­(NIPAm- co -MAA) microgels having 35% MAA, which are typically synthesized in our lab. , These microgels are labeled MG n ch - p MAA , where p MAA is the percentage of MAA. For example, MG100-10 is the microgel with n ch = 100 and x MAA = 0.1.…”

“…Culver et al have used functionalized poly­(NIPAm- co -MAA) nanogels for the binding and sensing of different proteins. Devices based on poly­(NIPAm- co -MAA) microgels have been recently investigated for the encapsulation/release of the chemotherapeutic drug doxorubicin (Doxo). − …”

“…The behavior of poly­(NIPAm- co -MAA) microgels, including their VPT and interaction with oppositely charged polymers, has been described using a variety of experimental techniques. − ,,− Theory and coarse grained molecular simulations have also been applied to investigate the behavior of stimuli-responsive polymer microgels. − These works have mainly focused on the swelling and other properties of particles having a permanently charged polymer network, − and some have addressed the effect of temperature and solvent quality. ,,,,, Recently, simulation studies have considered the pH response of microgels composed of charge-regulating polymers. − Only a few theoretical works, however, have investigated the properties of multiresponsive microgels as a function of temperature, pH, and salt concentration. , …”

Finding the sweet spot: a library of hydrogels with tunable degradation for tissue model development

“…PAA is a polycationic polymer of allylamine, which has several biomedical applications, including drug delivery, 22 protein, and nucleic acid delivery by forming complexes known as polyplexes. 23 It is also used as a component of transfection agents 24 and in the synthesis of microgels 25 and anti-microbial coatings. 26 PAA can be modified to promote mucoadhesion which is ideal for drug delivery systems and in vitro models.…”

Phosphonium versus Ammonium Compact Polyelectrolyte Complex Networks with Alginate—Comparing Their Properties and Cargo Encapsulation

“…Many different polycation/polyanion pairs have been explored for the creation of ionic networks. − Processes such as ultracentrifugation or extrusion were shown to transform the initial weak, fluid-like complexes into compacted PEC (CoPEC) networks with higher elasticity and tensile strength . These properties depend on network hydration, and the presence of salt was shown to result in a dynamic exchange between the ions, resulting in self-healing properties. − In polyion complex networks, ammonium-based polycations such as poly­(allylamine hydrochloride) − and poly­(diallyldimethylammonium chloride) − have been most thoroughly studied, while their analogous phosphonium polymers have been less explored. Ionically cross-linked polymer networks prepared from poly­(acrylic acid) and poly­(triethyl­(4-vinylbenzyl)­phosphonium chloride) were recently reported to self-heal in physiologically relevant salt concentrations .…”