Hollow Core−Porous Shell Structure Poly(acrylic acid) Nanogels with a Superhigh Capacity of Drug Loading

Abstract

Poly(acrylic acid) (PAA) nanogels with a hollow core-porous shell structure were prepared by the direct polymerization of an acrylic acid monomer in the presence of hydroxypropylcellulose (HPC) and a cross-linking agent, N,N-methylenebisacrylamide, followed by removal of HPC from the generated HPC-PAA nanoparticles in a basic environment. The properties of PAA nanogel were characterized by dynamic light scattering, FT-IR, transmission electron microscopy, and atomic force microscopy. It is found that the nanogels have a hollow core-porous shell structure. Protein, bovine serum albumin (BSA), and an antitumor agent, doxorubicin hydrochloride, were used as model drugs to investigate their loading abilities as versatile drug-delivery vehicles. The nanogel exhibits surprisingly high loading ability to both protein and small molecular drugs. For example, the maximum BSA loading capacity of PAA nanogel can reach as high as 800% (i.e., 1 mg of nanogel can load about 8.0 mg of BSA). This high loading capacity may be related with the hollow core-porous shell structure of PAA nanogels. PAA nanogels have also shown sustained drug release properties and can cross biological barriers to deliver loaded cargo inside cells. Considering the high stability of the materials, simple and mild preparation procedure, high loading capacity, sustained-release property, and ability to protect biological agents from denaturation, PAA nanogels should be promising drug-delivery carriers for drug-delivery systems.

Polymeric Hydrogel Nanocapsules: A Thermo and pH Dual-responsive Carrier for Sustained Drug Release

“…7(b). It could be observed that the cytotoxicity of Dox-loaded hydrogel capsules was almost equivalent to that of free Dox, implying that the drug efficacy released from the hydrogel capsules was scarcely influenced by the process of drug loading, which was in agreement with our previous work [32,34]. LCSM characterization was used to further examine cellular uptakes of PAA-PNIPAm hydrogel capsules.…”

“…Kozlovskaya group developed a series of weak polyacid based cross-linked capsules by hydrogen-bonded selfassembly as drug carriers [29][30][31]. In our previous work, various poly (acrylic acid) (PAA)-based micro/nanogels were prepared by using the precipitation polymerization method [32][33][34]. The obtained nanogels showed a high drug loading capacity and a sustained release feature for water-soluble drug molecules.…”

Photoluminescent PEG based comacromers as excitation dependent fluorophores for biomedical applications

“…The observed total intracellular distribution of PLM-NG was consistent with that of polyacrylic acid based nanogels which are believed to overcome cellular barriers and enter intracellular regions due to optimal size and bending of the plasma membrane. [38]. Taken together, these results…”

Degradable Thermoresponsive Nanogels for Protein Encapsulation and Controlled Release

“…Nanocarriers have shown very high drug loading capacity (sometimes as high as 800%, i.e., 1 mg of nanogel can load about 8.0 mg of BSA). 15 The success of using such nanocarriers relies on their ability for a controlled release of encapsulated drugs. Nanogels have been synthesized using various approaches: physical self-assembly, covalent cross-linking of preformed polymers, and template supported nanofabrication.…”