The stability of C-phycocyanin doped silica biomaterials in UV irradiation

Abstract

The synthesized C-phycocyanins (C-PCs) doped silica biomaterials were characterized by the SEM and BET surface area analysis measurement. The morphology of C-PCs doped silica biomaterials indicates that the surface of the silica cluster is formed by a great number of silica particles with an average size of between 30 and 40 nm. Silica itself is a porous structure with the average pore diameter of 2.95 nm. Pores with their diameter less than 5 nm account for 84.07%. In addition, the C-PCs can be utilized as a fluorescent protein probe to monitor influence of the protein encapsulation and to study matrix and protein interaction and stability of protein in silica matrix. Application of protein encapsulation silica materials requires biomolecules to keep bioactivity and stability on potentially unfavorable industrial conditions. The C-PCs in solution or in silicate matrix irradiated by ultraviolet ray can result in photobleaching, whereas the protein in the silica is less affected. The measured photodamage rate constant of C-PCs in buffer solution is 25 times faster than that of C-PCs in silica matrix. However, the lifetime of C-PCs in silica matrix or phosphate buffer is unaffected. These studies suggest that entrapment of C-PCs into silica matrixes not only can maintain their biological activity but also noticeably improve their photostability.

Keywords

C-phycocyanins / silica biomaterials / characterization / stability

References

[1] Glazer A. N. Phycobiliproteins—A Family of Valuable Widely Used Fluorophores[J]. J. Appl. Phycol., 1994, 6: 105-112.

[2] Miyasaka T., Koyama K., Itoh I. Quantum Conversion and Image Detection by a Bacteriorhodopsin-based Artificial Photoreceptor[J]. Science, 1992, 255: 342-347.

[3] Jin W., Brennan J. D. Properties and Applications of Proteins Encapsulated within Sol-gel Derived Materials[J]. Anal. Chim. Acta., 2002, 461: 1-12.

[4] Chen Z., Samuelson L. A., Akkara J., . Sol-Gel Encapsulated Light Transducing Protein Phycoerythrin: A New Biomaterial[J]. Chem. Mater., 1995, 7: 1779-1783.

[5] Stadnichuk I. N. Phycobiliproteins: Determination of Chromophore Composition and Content[J]. Phytochem. Anal., 1995, 6: 281-289.

[6] Gray B. H., Cosner J., Gantt E. Phycocyanins with Maxima Absorption at 637 nm and 623 nm from Agmenellum Quadruplicatum[J]. Photochem. Photobiol., 1976, 24: 299-303.

[7] Li Y., Yip W. T. Liposomes as Protective Capsules for Active Silica Sol-gel Biocomposite Synthesis[J]. J. Am. Chem. Soc., 2005, 127: 12756-12757.

[8] Apt K. E., Collier J. L., Grossman A. R. Evolution of Phycobiliproteins[J]. J. Mol. Biol., 1995, 248: 79-96.

[9] Swanson R. V., Zhou J., Learyll J. A., . Characterization of Phycocyanin Produced by cpcE and cpcF Mutants and Identification of an Intergenic Suppressor of the Defect in Bilin Attachment[J]. J. Biol. Chem., 1992, 267: 16146-16150.

[10] Lao K., Glazer A. N. Ultraviolet-B Photodestruction of a Light-harvesting Complex[J]. Proc. Natl. Acad. Sci., USA, 1996, 93: 258-264.

[11] Glazer A. N. Light Harvesting by Phycobilisomes[J]. Ann. Rev. Biophys. Biophys. Chem., 1985, 14: 47-77.

[12] Fischer M., Eider D. P. UV Effects on Photosynthesis and Phycobiliprotein Composition in the Flagellate Cyanophora Paradoxa[J]. FEMS Microbial. Ecol., 1992, 101: 121-131.

[13] Bhattacharya D., Basu S., Mandal P. C. UV Radiation Effects on Flavocytochrome b2 in Dilute Aqueous Solution[J]. J. Photochem. Photobiol. B. Bio., 2000, 59: 54-59.

[14] Viteri C. R., Gilliland J. W., Yip W. T. Probing the Dynamic Guest-host Interactions in Sol-Gel Films Using Single Molecule Spectroscopy[J]. J. Am. Chem. Soc., 2003, 125: 1980-1989.

[15] Xia A., Zhu J., Wu H., . Time-resolved Polarized Absorption of C-phycocyanins from Cyanobacterium Westiellopsis Prolifica. J. Photochem. Photobiol. B. Biol., 1993, 19: 111-117.

[16] Chirico G., Cannone F., Beretta S. Dynamics of Green Fluorescent Protein Mutant2 in Solution, on spin-coated Glasses and Encapsulated in Nanoporous Silica Gels[J]. Protein Sci., 2002, 11: 1152-1158.