Chitosan nanoparticles have been prepared using an ionic gelation method. The effects of freezedrying, cryoprotectant (D-trehalose) utilisation and ultrasonication time on the mean particle size, size distribution and stability of nanoparticles were investigated. The size distribution results indicated that freeze-drying caused the particles to agglomerate. Addition of the cryoprotectant and ul...

Recent studies have shown that L-proline is a natural osmoprotectant and an antioxidant to protect cells from injuries such as that caused by freezing and thawing in many species including plant, ram sperm and human endothelial cells. Nevertheless, this nontoxic cryoprotectant has not yet been applied to mammalian oocyte vitrification. In this study we evaluated the efficiency and safety of the...

A total of 410 goat embryos were divided at random into 9 groups. Cryoprotectants (glycerol, ethylene glycol or dimethylsulfoxide) were added by a 3-step procedure using increasing concentrations of cryoprotectant (0.5 M; 1 M; 1.5 M) in PBS at 10 min intervals. After freezing and thawing, each cryoprotectant was removed by 3 methods: the classic 3-step procedure (cryoprotectant 1 M-10 min; 0.5 ...

The purpose of the present study was to develop stable lyophilized formulation peginterferon alfa-2b which is acquiescent short lyophilization process. evaluates effect buffering components and cryoprotectant(s) on depegylation in combination with Finally, a process identified can produce pharmaceutical form without any during long-term storage. Formulations were analyzed mainly for by HP-size ...

Many plant species can be cryopreserved by treating shoot tips with complex cryoprotectant solutions before rapidly cooling them to liquid nitrogen temperatures. Plant vitrification solution 2 (PVS2), a commonly selected cryoprotectant, can be lethal with extended exposure times. To determine potentially toxic combinations, we have exposed mint shoot tips to one-, two-, three-, and four-compone...

OBJECTIVE To evaluate a cryopreservation technique by vitrification of whole ovaries with their vascular pedicle in sheep, by using two cryoprotectant solutions. DESIGN Animal study. SETTING Fertility clinic in a university teaching hospital. ANIMAL(S) Five to 6-month-old ewes. INTERVENTION(S) Whole sheep ovaries with their vascular pedicles were collected at the slaughterhouse and prep...

23 24 Large articular cartilage defects have proven difficult to treat and often result in 25 osteoarthritis of the affected joint. Cryopreservation of articular cartilage can provide an 26 increased supply of tissues for osteochondral allograft but cryoprotective agents are 27 required; however, few studies have been performed on the toxicity of these agents. This 28 study was designed to dete...

The objective was to test the hypothesis that the optimal cryoprotective agent for cryopreservation of human spermatozoa would be a solute for which cells have the highest plasma membrane permeability, resulting in the least amount of volume excursion during its addition and removal. To test this hypothesis, theoretical simulations were performed using membrane permeability coefficients to pred...