title: Crosslinking to enhance colloidal stability and redispersity of layered double hydroxide nanoparticles.
abstract: This article introduces a strategy for stabilizing and redispersing layered double hydroxide (LDH) nanoparticles by crosslinking bovine serum albumin (BSA) coated onto the surface. The strategy involves optimization of the amount of the crosslinking agent glutaraldehyde (GTA) to achieve minimal aggregation and ready redispersion. LDH nanoparticles were prepared by co-precipitation and hydrothermal treatment, with subsequent BSA coating at the BSA/LDH mass ratio of 5:2. BSA coated onto LDH nanoparticles was crosslinked with different amounts of GTA. Aggregation studies using dilution assays, dynamic light scattering, and zeta potential analysis indicated that severe aggregation at lower LDH nanoparticle concentrations can be prevented by proper crosslinking of BSA with GTA. The GTA-crosslinked BSA-coated nanoparticles showed excellent redispersity compared to the non-crosslinked nanoparticles. In vitro cytotoxicity and cell uptake were found to be minimally affected by GTA-crosslinking. The new strategy therefore provides a much more effective method for the prevention of LDH nanoparticle aggregation and improved LDH nanoparticle redispersion for use in a wide variety of bio-applications in vitro and in vivo.
authors.affiliation: Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD 4072, Australia.
authors.forename: Huali
authors.initials: H
authors.lastname: Zuo
authors.affiliation: Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD 4072, Australia. Electronic address: z.gu@uq.edu.au.
authors.forename: Zi
authors.initials: Z
authors.lastname: Gu
authors.affiliation: The Queensland Brain Institute, The University of Queensland, Queensland 4072, Australia.
authors.forename: Helen
authors.initials: H
authors.lastname: Cooper
authors.affiliation: Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD 4072, Australia. Electronic address: gordonxu@uq.edu.au.
authors.forename: Zhi Ping
authors.initials: ZP
authors.lastname: Xu
mesh_terms: D000818:Animals; D002417:Cattle; D003102:Colloids / Q000737:chemistry; D005976:Glutaral / Q000737:chemistry*; D006878:Hydroxides; D053758:Nanoparticles / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000737:chemistry*
chemical_list: D003102:Colloids; D006878:Hydroxides; D012710:Serum Albumin, Bovine; D005976:Glutaral
keywords: Bovine serum albumin (BSA); Crosslinking; Layered double hydroxide (LDH); Nanoparticle aggregation; Stabilisation