IOSR Journal of Pharmacy (IOSRPHR), www.iosrphr.org

IOSR Journal of Pharmacy

Vol. 2, Issue 1, Jan-Feb.2012, pp. 072-073

IOSR

Preparation of Chitosan Scaffolds for Tissue Engineering
using Freeze drying Technology

Tarun Garg, Arsh Chanana, Ravi Joshi

Seth G.L.Bihani S.D. college of technical education, Sri Ganganagar

INTRODUCTION

Chitosan has been processed in several forms to be used in tissue engineering applications, namely, membranes, particles,
fibers and 3-D fiber meshes. Chitosan may also be used as a drug delivery carrier, able to carry active agents or biomolecules
and growth factors. The preparation of these systems normally envolves freeze drying or lyophilizing a chitosan gel solution
[1].

MATERIALS AND METHODS

FREEZE-DRYING METHOD

Porous chitosan scaffold formulation was fabricated using freeze- drying method. Briefly chitosan was dissolved in 0.2 M
glacial acetic acid and solution was stored for 1 day at room temperature. After 1 day, solution was poured into stainless steel
mould and mould was stored in deep freezer at - 70°C for 5 days. After 5 days, mould was placed in lyophiliser (Martin
Christ alpha 1-2 LD plus, Germany) for 3 days. In the lyophiliser, preparation faced three phases. The first phase was
freezing phase - sample was exposed upto (- 40°C, vacuum 6.4mbar) for 10 min. The second phase was warm up vacuum
pump phase - sample was exposed upto (- 15°C, vacuum 1.4mbar) for 20 min. The third phase was main drying phase -
sample was exposed upto (30°C, vacuum 0.98 mbar) for 3 days and after 3 days, blank porous chitosan scaffold was prepared
[2].

SCAFFOLD CHARACTERIZATION

Scanning Electron Microscopy - SEM: The morphology and size of the scaffold formulations were examined using scanning
electron microscopy (SEM) (Jeol EVO-50, Japan). SEM figures of these scaffold formulations were taken after gold coating.
The sample was placed on the grid and the grid was allowed to dry at ambient temperature and samples were viewed under
scanning electron microscope and photographs were taken at suitable magnification [3].

RESULTS AND DISCUSSION

Chitosan scaffold formulations were white in the dry form, smooth, soft, sponge-like, flexible and strong enough to handle in
dry conditions without deformation. The photographs and SEM micrographs of scaffold formulation was shown in Fig. 1.
The SEM images show that 3D pore microstructures in all chitosan scaffolds were heterogeneous, with well interconnected
pores. The mean diameter of pores on scaffold formulation was found in the range of 10-20 urn.

Fig.l. Characterization of chitosan porous matrix scaffold formulation. Photographs of top and SEM views of scaffold

formulation respectively.

porous chitosan scaffold formulations were successfully prepared by the freeze-drying method. Freeze-drying method allow a
faster preparation, highly porous structure with high pore inter-connectivity. Main advantage of this technique is that, it
neither requires high temperature nor separate leaching step. The pore size can be controlled by optimizing the freezing rate
and pH; a fast freezing rate produces smaller pores. Freezing temperature, vacuum pressure and time period are very
important factors which effect the formation of porous scaffold.

ISSN: 2250-3013

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72 I P a g e

IOSR Journal of Pharmacy

Vol. 2, Issue 1, Jan-Feb.2012, pp. 072-073

IOSR

CONCLUSIONS

In this work we evaluate the feasibility of processing chitosan 3D scaffolds for tissue engineering applications using freeze
drying technology. Freeze drying technology was used to precipitate chitosan from acetic acid solutions and used
successfully as a drug delivery carrier, able to carry active agents or biomolecules and growth factors.

REFERENCES

[1]. T. C. Santos, A. P. Marques, S. S. Silva, J. M. Oliveira, J. F. Mano, A. G. Castro, R. L. Reis, Journal of

Biotechnology, 132,2007,218-226.

[2]. S.V. Madihally, H.W.T. Matthew, Porous chitosan scaffolds for tissue engineering, Biomaterials, 20,

1999,1133-1142.

[3]. H.W. Kim, J.C. Knowles, H. Kim, Hydroxyapatite/poly(e-caprolactone) composite coatings on

hydroxyapatite porous bone scaffold for drug delivery, Biomaterials, 25, 2004, 1279-1287.

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