Discipline: Chemistry and Chemical Sciences
Subcategory: Biochemistry (not Cell and Molecular Biology and Genetics)
Yasmeen Solano - California State University, Los Angeles
Co-Author(s): Tatsuhiro Kodama, School of Aeronautics and Astronautics, Purdue University; Alina Alexeenko, School of Aeronautics and Astronautics, Purdue University; Evgenyi Shalaev, Allergan, Inc. 2525 Dupont Dr, Irvine, CA 92612; Xin Wen, Department of Chemistry and Biochemistry, California State University, Los Angeles
Crystallization of excipients during freeze- drying is often undesirable, it could lead to distribution of water in the matrix of the freeze- dried product resulting in destabilization of the freeze-dried products and/or cause vial breakage.Antifreeze proteins (AFPs) are found in many organisms including bacteria, fish, plants, and insects and are well-known for their ability to bind to ice crystals and inhibit ice growth. New roles for AFPs in controlling carbohydrate crystallization have been recently reported by Dr. Xin Wen?s lab at California State University, Los Angeles, where AFPs have been demonstrated to inhibit the solute crystallization highly effectively. In this study, we investigated the effects of AFP’s on the crystallization of mannitol during freeze-drying and analyzed the resulting freeze-dried solids using polarized microscopy and powder X-ray diffractometer. The results suggest that the presence of AFPs at micro-molar alters the temperature of ice nucleation and inhibits the crystallization of mannitol during freeze-drying. In addition, the powder X-ray diffraction (PXRD) data suggests that AFPs inhibit the mannitol crystals and alters the forms of mannitol crystals. The effects of AFPs on mannitol crystallization during freeze-drying is concentration dependent and are more significant when there is an additional component in the system, such as lactate dehydrogenase. The mechanistic details for these effects by AFPs are currently being studied. These studies are important to further understand the novel properties and mechanisms of AFPs and suggest potential applications for AFPs in freeze-drying process to eliminate deterioration of industrial samples due to excipients crystallization.
Funder Acknowledgement(s): The general supports from the grants NIH GM086249 and NSF1644917 to X.W. The general supports from Advanced Lyophilization Technology Hub (LyoHub)
Faculty Advisor: Dr. Xin Wen, email@example.com
Role: I took part in the purification process of the antifreeze protein at California State University, Los Angeles. In addition, I conducted studies at Purdue University where I made , tested and analyzed samples.