title: Augmenting protein release from layer-by-layer functionalized agarose hydrogels.
abstract: Recent work demonstrated the efficacy of combining layer-by-layer assembly with hydrogels to provide the controlled delivery of proteins for use in nerve repair scaffolds. In this work, we augmented the protein dose response by controlling and increasing the hydrogel internal surface area. Sucrose was added to agarose during gelation to homogenize the nanopore morphology, resulting in increased surface area per unit volume of hydrogel. The surface area of a range of compositions (1.5-5.0 wt% agarose and 0, 50 and 65 wt% sucrose) was measured. Gels were supercritically dried to preserve porosity enabling detailed pore morphology measurements using nitrogen adsorption and high resolution scanning electron microscopy. The resulting surface area, normalized by superficial gel volume, ranged between 6m(2)/cm(3)gel and 56 m(2)/cm(3)gel. Using the layer-by-layer process to load lysozyme, a neurotrophic factor analog, a relationship was observed between surface area and cumulative dose response ranging from 176 to 2556 μg/mL, which is in the range of clinical relevance for the delivery of growth factors. In this work, we demonstrated that the ability to control porosity is key in tuning drug delivery dose response from layer-by-layer modified hydrogels.
authors: Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA.
authors: Daniel
authors: D
authors: Lynam
authors: Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA.
authors: Chelsea
authors: C
authors: Peterson
authors: Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA.
authors: Ryan
authors: R
authors: Maloney
authors: Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA.
authors: Dena
authors: D
authors: Shahriari
authors: Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA.
authors: Alexa
authors: A
authors: Garrison
authors: Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA.
authors: Sara
authors: S
authors: Saleh
authors: Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA.
authors: Sumit
authors: S
authors: Mehrotra
authors: Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA; Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA.
authors: Christina
authors: C
authors: Chan
authors: Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA. Electronic address: jsakamot@msu.edu.
authors: Jeff
authors: J
authors: Sakamoto
mesh_terms: D020100:Hydrogels / Q000737:chemistry*; D010316:Particle Size; D011506:Proteins / Q000737:chemistry*; D012685:Sepharose / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D020100:Hydrogels; D011506:Proteins; D012685:Sepharose
keywords: Controlled drug release; Hydrogel; Layer-by-layer; Pore refinement; Surface area