Biological applications of weal polyelectrolyte multilayers

This thesis research focused on biological applications of ultra-thin weak polyelectrolyte multilayers with specific emphasis on cell patterning, drug delivery, and antibacterial coatings. All of these very different applications were studied using three different polymers - polyacrylic acid (PAA), poly(allylamine hydrochloride) (PAH), polyacrylamide (PAAm). The first part of this thesis focuses on patterning polyelectrolyte multilayers found to resist mammalian cell adhesion, with ligands that promote specific interactions for adhesion. It was found that by patterning PAH on polyelectrolyte multilayers, the patterned functional group density and thickness could be tuned through ink pH adjustment. By changing the surface density of amine groups in the PAH patterns, the ligand density could also be altered using specific chemistry to attach peptides containing the tri-peptide sequence, RGD, which is known to promote cell adhesion in a number of cell types. The RGD density in the patterned regions determined the number of cells attached and the amount of cytoskeletal protein organization. The second part is an evaluation of porous polyelectrolyte multilayers as a delivery system for controlled release of small molecule drugs. The loading and releasing properties of porous PAH/PAA multilayers were investigated using the two drugs, ketoprofen and cytochalasin D. It was determined that the amount of drug released was proportional to the number of porous layers. Nanoporous films showed zero-order release, whereas microporous films displayed Fickian diffusion. The efficacy of the released drugs was checked by monitoring the effect of released cytochalasin D on fibroblasts' division.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Chemical Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2005

Author dc:creator

• Berg, Michael C., Ph. D. Massachusetts Institute of Technology

Advisor dc:contributor.advisor

• Paula T. Hammond and Michael F. Rubner.

• Chemical Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/33599

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/33599