{"title":"Viscoelastic properties of decellularized and freeze-dried human dermis between i909c and 40cC.","authors":"Q P Jia, S L Huang, Y T Tang, W Q Sun","doi":"","DOIUrl":null,"url":null,"abstract":"<p><strong>Background: </strong>Human donor skin is processed to make the acellular dermis matrix (ADM) for tissue repair and regeneration. There is no data on the viscoelastic properties of ADM at room and subzero temperatures.</p><p><strong>Objective: </strong>The work evaluated the temperature dependence of viscoelastic properties of freeze-dried ADM.</p><p><strong>Materials and methods: </strong>Donor skin was de-epidermized, de-cellularized and freeze-dried with trehalose as the lyo-protectant. Glass transition of freeze-dried ADM was measured by differential scanning calorimeter (DSC), and viscoelastic properties were examined by dynamic mechanical analyzer (DMA).</p><p><strong>Results: </strong>At the low moisture range (1.4 +/- 0.5%), the glass transition temperature (Tg) of freeze-dried ADM was 90 degree C to 100 degree C. As the moisture content increased, the Tg decreased steadily. At the high moisture range (10.8 +/- 2.9%), the Tg was 40 degree C to 60 degree C. There were large donor-to-donor variations in viscoelastic properties of freeze-dried ADM as demonstrated by the changes in storage modulus (G'), loss modulus (G\") and damping factor tan delta (G\"/G'). However, the trends of the temperature dependence for G', G\" and tan delta were similar among all 8 donors. For each donor, changes in G' and G\" were relatively small between -90 degree C and 40 degree C, and G' was at least one order of magnitude greater than G\". Two viscoelastic relaxations were observed in freeze-dried ADM, one at -20 degree C and the other at -60 degree C respectively.</p><p><strong>Conclusion: </strong>Freeze-dried ADM was protected in the glassy carbohydrate matrix. DMA observed two viscoelastic relaxations (i.e., alpha process at -20 degree C and beta process at -60 degree C). Overall changes in G' and G'' of freeze-dried ADM were relatively small within one order of magnitude between -90 degree C and 40 degree C. https://doi.org/10.54680/fr24110110612.</p>","PeriodicalId":10937,"journal":{"name":"Cryo letters","volume":"45 1","pages":"55-59"},"PeriodicalIF":1.0000,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Cryo letters","FirstCategoryId":"99","ListUrlMain":"","RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Background: Human donor skin is processed to make the acellular dermis matrix (ADM) for tissue repair and regeneration. There is no data on the viscoelastic properties of ADM at room and subzero temperatures.
Objective: The work evaluated the temperature dependence of viscoelastic properties of freeze-dried ADM.
Materials and methods: Donor skin was de-epidermized, de-cellularized and freeze-dried with trehalose as the lyo-protectant. Glass transition of freeze-dried ADM was measured by differential scanning calorimeter (DSC), and viscoelastic properties were examined by dynamic mechanical analyzer (DMA).
Results: At the low moisture range (1.4 +/- 0.5%), the glass transition temperature (Tg) of freeze-dried ADM was 90 degree C to 100 degree C. As the moisture content increased, the Tg decreased steadily. At the high moisture range (10.8 +/- 2.9%), the Tg was 40 degree C to 60 degree C. There were large donor-to-donor variations in viscoelastic properties of freeze-dried ADM as demonstrated by the changes in storage modulus (G'), loss modulus (G") and damping factor tan delta (G"/G'). However, the trends of the temperature dependence for G', G" and tan delta were similar among all 8 donors. For each donor, changes in G' and G" were relatively small between -90 degree C and 40 degree C, and G' was at least one order of magnitude greater than G". Two viscoelastic relaxations were observed in freeze-dried ADM, one at -20 degree C and the other at -60 degree C respectively.
Conclusion: Freeze-dried ADM was protected in the glassy carbohydrate matrix. DMA observed two viscoelastic relaxations (i.e., alpha process at -20 degree C and beta process at -60 degree C). Overall changes in G' and G'' of freeze-dried ADM were relatively small within one order of magnitude between -90 degree C and 40 degree C. https://doi.org/10.54680/fr24110110612.
期刊介绍:
A bimonthly international journal for low temperature sciences, including cryobiology, cryopreservation or vitrification of cells and tissues, chemical and physical aspects of freezing and drying, and studies involving ecology of cold environments, and cold adaptation
The journal publishes original research reports, authoritative reviews, technical developments and commissioned book reviews of studies of the effects produced by low temperatures on a wide variety of scientific and technical processes, or those involving low temperature techniques in the investigation of physical, chemical, biological and ecological problems.