Thermoresponsive polymeric nanoparticles based on poly(2‐oxazoline)s and tannic acid

Abstract

Hydrogen bonding is widely present and plays a significant role in material science and supramolecular chemistry. This work reports a straightforward strategy for the preparation of polymeric nanoparticles from neutral poly(2‐oxazoline)s (POx) and tannic acid (TA) driven by their intermolecular hydrogen bonding. Dynamic light scattering (DLS) and scanning electron microscope (SEM) measurements showed that POx bearing different substituents, that is, methyl, ethyl and n‐propyl in the 2‐position all could assemble with TA into stable nanoparticles in water or ethanol. The diameter of the assembled nanoparticles could be manipulated by varying parameters such as molecular weight of POx, concentration and ratio of POx, and TA. Interestingly, POx/TA nanoparticles exhibited upper critical solution temperature (UCST)‐type thermoresponsive properties in ethanol or water depending on the molecular weight and substituent in the 2‐position of POx. Increasing or decreasing the temperature at the transition point resulted in the reversible transformation between assembled nanoparticles and disassembled poly(2‐n‐propyl‐2‐oxazoline) (PnPrOx) and TA. In view of the tailored size of the stable nanoparticles and the biocompatibilities of POx and TA, the prepared thermoresponsive nanoparticles are promising candidates as carriers for medicine toward related biomedical applications. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 1520–1527

Inhaled ciprofloxacin-loaded poly(2-ethyl-2-oxazoline) nanoparticles from dry powder inhaler formulation for the potential treatment of lower respiratory tract infections

“…Blank PEtOx NPs were prepared by a modified coassembly reaction between the neutral PEtOx polymer and TA [ 8 ]. To assemble blank PEtOx NPs, PEtOx was dissolved in 1% w/v deionized water using ultrasonication for 5 minutes to obtain 20 mL PEtOx solution.…”

“…Controlled release of drug using drug-loaded polymer nanoparticles (NPs) has shown promising effects over conventional drug delivery systems including, extended duration of action, enhanced therapeutic effects, limited dose-related complications, and increased patience compliance [ 5 ]. The polymers provide some added benefits to use as potential drug carriers including ease formulation characteristics, manageable particle sizes, protecting the formulated drugs from degradation in unfavourable environments [ 8 ]. Both synthetic and natural polymers have been investigated for lung delivery and showed benefits over drug alone formulations including prolonged drug release, enhanced dispersibility, improved cellular uptake, and bioavailability [ 5 ].…”

Medical Applications Based on Supramolecular Self-Assembled Materials From Tannic Acid

“…Polymer nanoparticles/microparticles based on non-covalent interaction are a kind of soft material that can be used as effective delivery systems with properties of a stimulus response, self-healing, and controlled release, and they are very attractive in biomedical and related applications (Wang et al, 2018a ). Nanoparticles/microparticles based on hydrogen bonding have been widely studied as a delivery system in recent years.…”

“…Supramolecular assembly, which originated from Lehn's groundbreaking work on host–guest self-assembly in 1987 (Lehn, 1988 ), is a process of spontaneous formation of unique nanostructures by dynamic covalent interactions (Wang et al, 2018a ) and non-covalent intermolecular interactions (Caulder and Raymond, 1999 ), including hydrogen bonds, hydrophobic interactions, electrostatic interactions, van der Waals forces, and π-π stacking. It originates from biological systems and is widely applied in the biomedical field (Cui and Xu, 2017 ).…”

Self-assembled poly(2-ethyl-2-oxazoline)/malonic acid hollow fibers in aqueous solutions

“…Physicochemical properties such as solubility in water, crystallinity, temperature-responsiveness, of PAOX polymers depend on the structure and the length of the side chains [33][34][35]. Driven by their biocompatibility together with exceptional physico-chemical properties, POX have recently been much studied especially regarding the utilization of microparticles, microspheres or microbeads, layer-by-layer capsules or films, micelles, polymersomes or nanogels in biological applications [24,[36][37][38]. On the self-assembly side, formation of crystalline nanofibers above the cloud point temperature (Tcl) in aqueous solutions of poly(2-isopropyl-2-oxazoline) (PIPOX) [26,27] and PEOX [28] (Chart 1a) was previously reported.…”