title: Electrostatic surface modifications to improve gene delivery.
abstract: BACKGROUND
  Gene therapy has the potential to treat a wide variety of diseases, including genetic diseases and cancer.
  
  
  METHODS
  This review introduces biomaterials used for gene delivery and then focuses on the use of electrostatic surface modifications to improve gene delivery materials. These modifications have been used to stabilize therapeutics in vivo, add cell-specific targeting ligands, and promote controlled release. Coatings of nanoparticles and microparticles as well as non-particulate surface coatings are covered in this review. Electrostatic principles are crucial for the development of multilayer delivery structures fabricated by the layer-by-layer method.
  
  
  RESULTS
  The reader will gain knowledge about the composition of biomaterials used for surface modifications and how these coatings and multilayers can be utilized to improve spatial control and efficiency of delivery. Examples are shown for the delivery of nucleic acids, including DNA and siRNA, to in vitro and in vivo systems.
  
  
  CONCLUSIONS
  The versatile and powerful approach of electrostatic coatings and multilayers will lead to the development of enhanced gene therapies.
authors.affiliation: Johns Hopkins University School of Medicine, Department of Biomedical Engineering, 400 N. Broadway, Smith Building 5017, Baltimore, MD 21231, USA.
authors.forename: Ron B
authors.initials: RB
authors.lastname: Shmueli
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Anderson
authors.forename: Jordan J
authors.initials: JJ
authors.lastname: Green
mesh_terms: D001672:Biocompatible Materials; D018014:Gene Transfer Techniques; D053758:Nanoparticles; D009696:Nucleic Acids / Q000008:administration & dosage*; D055672:Static Electricity
chemical_list: D001672:Biocompatible Materials; D009696:Nucleic Acids