Abstract: A porous hollow silica particle with an interpolymer complex immobilized thereon is provided. The interpolymer complex comprises a first polymer immobilized to a surface of the silica particle, and a second polymer complexed with the first polymer. Pharmaceutical compositions comprising the silica particle, and methods of forming the silica particle are also provided.

Abstract: A porous hollow silica particle with an interpolymer complex immobilized thereon is provided. The interpolymer complex comprises a first polymer immobilized to a surface of the silica particle, and a second polymer complexed with the first polymer. Pharmaceutical compositions comprising the silica particle, and methods of forming the silica particle are also provided.

Abstract: A porous hollow silica particle with an interpolymer complex immobilized thereon is provided. The interpolymer complex comprises a first polymer immobilized to a surface of the silica particle, and a second polymer complexed with the first polymer. Pharmaceutical compositions comprising the silica particle, and methods of forming the silica particle are also provided.

Abstract: A porous hollow silica particle with an interpolymer complex immobilized thereon is provided. The interpolymer complex comprises a first polymer immobilized to a surface of the silica particle, and a second polymer complexed with the first polymer. Pharmaceutical compositions comprising the silica particle, and methods of forming the silica particle are also provided.

Abstract: In a process for forming a hydrogel, a precursor crosslinkable through disulfide bonds for forming the hydrogel is provided in a solution. The precursor comprises a branched molecular structure, which comprises a plurality of branches. At least three of the branches each comprises a disulfide bond. The pH in the solution is adjusted to initiate thiol-disulfide exchange in the precursor, thus crosslinking the precursor through disulfide bonds formed by thiol-disulfide exchange. After the precursor is sufficiently crosslinked to form a hydrogel, the pH in the solution is adjusted to inhibit further thiol-disulfide exchange in the hydrogel. Further, a hydrogel matrix may comprise a polymer substantially crosslinked through disulfide bonds. The polymer may comprise a hydrophobic poly(amido amine) core and an amino-functionalized hydrophilic shell.

Abstract: The present invention provides a porous hollow silica micro- or nanoparticle with a polymer grafted thereon, wherein the polymer is selected from poly(methacrylic acid) and copolymers thereof. The polymer may be covalently linked to the silica particle via a bridging group. Provided is also a method of covalently coupling a poly(methacrylic acid) to a silica surface of a hollow silica particle. The method comprises contacting a silica surface of a hollow silica particle that carries amino functional or halogen functional groups with a poly(methacrylic acid) or a copolymer or a respective monomer thereof. The method further comprises allowing the carboxyl group of the monomer or the poly(methacrylic acid) and an amino functional group or a halogen functional group on the silica surface to undergo a coupling reaction, thereby covalently coupling the polymer to the silica surface.

Abstract: In a process for forming a hydrogel, a precursor crosslinkable through disulfide bonds for forming the hydrogel is provided in a solution. The precursor comprises a branched molecular structure, which comprises a plurality of branches. At least three of the branches each comprises a disulfide bond. The pH in the solution is adjusted to initiate thiol-disulfide exchange in the precursor, thus crosslinking the precursor through disulfide bonds formed by thiol-disulfide exchange. After the precursor is sufficiently crosslinked to form a hydrogel, the pH in the solution is adjusted to inhibit further thiol-disulfide exchange in the hydrogel. Further, a hydrogel matrix may comprise a polymer substantially crosslinked through disulfide bonds. The polymer may comprise a hydrophobic poly(amido amine) core and an amino-functionalized hydrophilic shell.