Unit for Reproductive Medicine - Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany.
Biostabilization Laboratory - Lower Saxony Centre for Biomedical Engineering, Implant Research and Development, University of Veterinary Medicine Hannover, Stadtfelddamm 34, Hannover, 30625, Germany.
Sci Rep. 2020 Dec 8;10(1):21442. doi: 10.1038/s41598-020-78306-1.
Saliva has been widely recognized as a non-invasive, painless and easy-to-collect bodily fluid, which contains biomarkers that can be used for diagnosis of both oral and systemic diseases. Under ambient conditions, salivary biomarkers are subject to degradation. Therefore, in order to minimize degradation during transport and storage, saliva specimens need to be stabilized. The aim of this study was to investigate the feasibility of preserving saliva samples by drying to provide a shelf-stable source of DNA. Human saliva was dried on filters under ambient conditions using sucrose as lyoprotective agent. Samples were stored under different conditions, i.e. varying relative humidity (RH) and temperature. In addition to assessment of different cell types in saliva and their DNA contents, Fourier transform infrared spectroscopy (FTIR) was used to evaluate the effects of storage on biomolecular structure characteristics of saliva. FTIR analysis showed that saliva dried without a lyoprotectant exhibits a higher content of extended β-sheet protein secondary structures compared to samples that were dried with sucrose. In order to evaluate differences in characteristic bands arising from the DNA backbone among differently stored samples, principal component analysis (PCA) was performed, allowing a clear discrimination between groups with/without sucrose as well as storage durations and conditions. Our results indicated that saliva dried on filters in the presence of sucrose exhibits higher biomolecular stability during storage.
唾液已被广泛认为是一种非侵入性、无痛且易于采集的体液，其中包含可用于诊断口腔和全身疾病的生物标志物。在环境条件下，唾液生物标志物容易降解。因此，为了在运输和储存过程中尽量减少降解，需要对唾液样本进行稳定化处理。本研究旨在探讨通过干燥来保存唾液样本的可行性，以提供一种稳定保存的 DNA 来源。将人类唾液在环境条件下用蔗糖作为冷冻保护剂干燥在滤纸上。将样品在不同条件下储存，即不同的相对湿度 (RH) 和温度。除了评估唾液中的不同细胞类型及其 DNA 含量外，傅里叶变换红外光谱 (FTIR) 还用于评估储存对唾液生物分子结构特征的影响。FTIR 分析表明，与用蔗糖干燥的样品相比，未用冷冻保护剂干燥的唾液中具有更高含量的伸展β-折叠蛋白质二级结构。为了评估不同储存条件下源自 DNA 骨架的特征带之间的差异，进行了主成分分析 (PCA)，允许清楚地区分有/无蔗糖以及储存时间和条件的组。我们的结果表明，在存在蔗糖的情况下，用滤纸干燥的唾液在储存过程中表现出更高的生物分子稳定性。
