RT Journal Article SR Electronic T1 Freeze-Thaw Studies of a Model Protein, Lactate Dehydrogenase, in the Presence of Cryoprotectants JF PDA Journal of Pharmaceutical Science and Technology JO PDA J Pharm Sci Technol FD Parenteral Drug Association (PDA) SP 76 OP 83 VO 47 IS 2 A1 Nema, Sandeep A1 Kenneth, E. Avis YR 1993 UL http://journal.pda.org/content/47/2/76.abstract AB The objective of this study was to investigate the behavior of lactate dehydrogenase (LDH).upon freezing and thawing, alone or in the presence of several selected cryoprotectants. Also,-the influence of the freezing rate on retainment of LDH activity was investigated. It was observed that fast freezing caused less loss of LDH activity than slow freezing. The probable mechanisms of loss of activity after freeze-thaw cycles were discussed. Selected cryoprotectants were evaluated for their ability to protect LDH during freeze-thaw cycles. Surface tension and pH change measurements upon freezing of the cryoprotectant solutions were carried out. Based on the results of these experiments, a potential mechanism of cryoprotection has been developed.