Dextran Hydrogel Rheology and Dextranase Enzyme Activity

1
Dextran- Hydrogel Rheology and Dextranase Enzyme
Activity

• P. Crockett, M. Lee, R. Composto Drexel
  RET-NANO Program, Department of Material Science
  and Engineering

2
Introduction

• Hydrogels are used for a wide array of
  biomaterials applications, such as contact
  lenses, drug delivery vehicles, and tissue
  adhesives.
• The favorable properties of Hydrogels include
  Hydrophilicity, elasticity, and can be modulated
  chemically.
• Dextrans are carbohydrate polymers with
  properties that mimic biological sugars found on
  tissue surfaces.
• Dextran coated surfaces can be used to grow up
  cells to later be cleaved as a sheet via
  Dextranase..

3
Materials and Methods

• The first part of our research focused on how
  Dextran-GMA Hydrogel compliance varies with
  concentration.
• The second part of our research was focused on
  the effect of Dextranase on our Dextran.
• Once the optimal pH and temperature are found, we
  hope to compare and contrast Dextranase activity
  with Dextran and Dextran-GMA Hydrogel.

4
(No Transcript)
5
(No Transcript)
6
(No Transcript)
7
(No Transcript)
8
(No Transcript)
9
Conclusions

• Dextran-GMA Hydrogels were analyzed at various
  concentrations using rheometry. Hydrogel
  compliance increased linearly with concentration.
• A color change assay was produced using optimal
  Maltose concentrations.
• Enzyme activity was found to degrade 2 Dextran
  at close to suppliers specifications.
• Dextranase was found to have negligible activity
  difference at pH 6 and pH 7.
• Enzyme activity proved to be significantly
  enhanced by activator at pH 6 but lost it
  effectiveness at pH 7.

10
(No Transcript)
11
(No Transcript)
12
(No Transcript)
13
(No Transcript)
14
References

• 1. Influence of the degradation mechanism of
  Hydrogels on their elastic and swelling
  properties during degradation
• Meyvis, T.K.L. (Ghent Univ) De Smedt, S.C.
  Demeester, J. Hennink, W.E. Source
  Macromolecules, v 33, n 13, Jun, 2000, p
  4717-4725
• 2.Swelling pressure of Hydrogels that degrade
  through different mechanisms
• Stubbe, B.G. (Lab. Gen. Biochem. and Phys.
  Pharm., Department of Pharmaceutics, Ghent
  University) Hennink, W.E. De Smedt, S.C.
  Demeester, J. Source Macromolecules, v 37, n
  23, Nov 16, 2004, p 8739-8744
• 3.Enzymatic degradation of cross-linked Dextrans
• Franssen, O. (Universiteit Utrecht) van Ooijen,
  R.D. de Boer, D. Maes, R.A.A. Hennink, W.E.
  Source Macromolecules, v 32, n 9, May, 1999, p
  2896-2902

15
Acknowledgments

• I would like to thank Dr. Composto and Dr.
  Boettiger for allowing me the opportunity to
  utilize their laboratory resources. Dr. Mark Lee
  for being an excellent teacher and providing me
  with an exciting project to work on. Drexel
  RET-NANO for allowing this teacher to the
  opportunity to bring cutting edge research back
  to my students.