Poly(ethylene glycol) and poly(N-vinlypyrrolidone) for improved porcine islet cryopreservation

Dong Xie, Sherly Jules, Yiming Weng, Yuan Zhou, Richard A. Sidner, Mark Pescovitz

Department of Biomedical Engineering, Purdue School of Engineering and Technology, Indiana University-Purdue University, Indianapolis, USA.
Department of Surgery, School of Medicine, Indiana University, Indianapolis, USA.

DOI: 10.4236/jbise.2012.55033                

Abstract

Water-soluble polymers poly(ethylene glycol) (PEG) and poly(N-vinylpyrrolidone) (PVP) were used to study cryopreservation of porcine islets. DMSO was used as control. The effects of polymer purity, molecular weight (MW) and concentration on islet viability were investigated. The results show that both PVP and PEG are good cyroprotectant candidates for islet cryopreservation. The effects of polymer purity and concentration were significant. Increasing concentration significantly increased the islet viability. However, after the concentration reached a certain level, there was no significant difference in viability probably due to increased viscosity of the polymer solution. The effect of polymer MW was not significant. It is concluded that polymers can be a suitable cryoprotectant for porcine islet cryopreservation. The islet viability is polymer concentration-dependent. It seems that PVP is a better cryoprotectant candidate as compared to PEG because the former showed a fast dissolution rate in culture medium and lower viscosity. The polymer concentration at 30% appears to be the optimal for cryopreservation from the viewpoint of islet viability and medium viscosity.

Keywords

Poly (Ethylene Glycol); Poly(N-Vinylpyrrolidone); Porcine Islet; Cryopreservation; Cell Viability; Viscosity

Conflicts of Interest

The authors declare no conflicts of interest.

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