Silicone-Biopolymer Copolymers:

Silicone- Biopolymer Copolymers

Michael A. Brook
Professor

Silicones have many unusual properties, including interesting biochemistry in its own right (for example, in the bioprocessing of silica). Although there has been concern over the safety of silicone in implanted breast prostheses, they remain among the safest polymeric materials for use in biomedical applications such as topical applications. We believe that combining hydrophobic silicones with hydrophilic biopolymers will allow the preparation of new materials for biomedical and other applications. Some of our current interests are listed below.

Silicone-Based Biomaterials

UNDER CONSTRUCTION

Proteins and Silicones: Oral Vaccines (see also Protein-Silicone Emulsions)

Proteins are typically injected for use as vaccines. There are many disadvantages to this and there are many potential advantages to oral vaccines. We have found that silicone-grafted starch protein microspheres (Figure 1) induce antibody production when given orally to mice (Scheme 1).^{47,65,66,71,73,74,77,81,82,87,88} We are trying to establish the chemical nature of the interaction between the silicone and the biopolymers and also trying to develop a model for the bioactivity of the spheres in conjuction with colleagues in the Department of Pathology.

Figure 1

Starch and Cellulose and Silicones: New Materials - New Properties

We are using the technology described above to examine starch-silicone and cellulose-silicone composites. The effectiveness of the hydrophobization is particularly clear with filter paper. The left side shows normal paper - water is rapidly absorbed. In contrast, the water on the silicone modifed paper on the right evaporates before it penetrates the paper.

Wood-Polyethylene Composites

Similarly, we are examining ways to use silicon chemistry to graft polyethylene to wood fibres.

Publications

93. F Bartzoka, V.; McDermott, M. R.; Brook, M. A., Protein-Silicone Interactions at Liquid/Liquid Interfaces, In Emulsions, Foams and Thin Films, Mittal, K. L.; Kumar, P., Eds., Dekker, New York, 2000, Chap. 21, pp. 371-380, Invited manuscript.

92. F Vasiliki Bartzoka, Gladys Chan and Michael A. Brook, Protein-Silicone Synergism at Liquid/Liquid Interfaces, Langmuir 2000, 16, 4589-4593.

87. C M. R. McDermott, M. A. Brook, V. Bartzoka, Adjuvancy effect of different types of silicone gel (Letter to the Editor commenting on the paper by Naim et al. (J. Biomed. Mater. Res. 1997, 37, 5341), J. Biomed. Mater. Res. 1999, 46, 132-133.

82. R Vasiliki Bartzoka, Mark R. McDermott and Michael A. Brook Protein-Silicone Interactions, Advan. Mater. 1999, 11, 257-259, invited manuscript.

81. F Heritage, P. L.; Underdown, B. J.; Brook, M. A.; and McDermott, M. R. Oral Administration of Polymer-Grafted Starch Microparticles Activates Gut-Associated Lymphocytes and Primes Mice for a Subsequent Systemic Antigen Challenge, Vaccine 1998, 16, 2010.

77. F McDermott, M. R.; Heritage, P. L.; Bartzoka, V.; Brook, M. A. Polymer-grafted Starch Microparticles for Oral and Nasal Administration, Immunol. Cell Biol. 1998, 76, 256-262.

74. F Vasiliki Bartzoka, Michael A. Brook, and Mark R. McDermott, Protein-Silicone Interactions: How Compatible Are The Two Species? Langmuir 1998, 14, 1887-1891.

73. F Vasiliki Bartzoka, Michael A. Brook, and Mark R. McDermott, Silicone-Protein Films: Establishing the Strength of the Protein-Silicone Interaction Langmuir1998, 14, 1892-1898.

71. F Heritage, P. L.; Brook, M. A.; Underdown, B. J. and McDermott, M. R.; Oral Intranasal Immunization with Polymer-Grafted Microparticles Activates the Natal-Associated Lymphoid Tissue and Draining Lymph Nodes, Immunology. 1998, 93, 249-256.