Castillo-Peinado L S, Calderón-Santiago M, Priego-Capote F
Department of Analytical Chemistry, Annex Marie Curie Building, Campus of Rabanales, University of Córdoba, Córdoba, Spain; Maimónides Institute of Biomedical Research (IMIBIC), Reina Sofía University Hospital, University of Córdoba, Córdoba, Spain; Nanochemistry University Institute (IUNAN), Campus of Rabanales, University of Córdoba, Córdoba, Spain; CIBER Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Spain.
Department of Analytical Chemistry, Annex Marie Curie Building, Campus of Rabanales, University of Córdoba, Córdoba, Spain; Maimónides Institute of Biomedical Research (IMIBIC), Reina Sofía University Hospital, University of Córdoba, Córdoba, Spain; Nanochemistry University Institute (IUNAN), Campus of Rabanales, University of Córdoba, Córdoba, Spain; CIBER Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Spain.
Talanta. 2021 Jan 15;222:121692. doi: 10.1016/j.talanta.2020.121692. Epub 2020 Sep 24.
Determination of vitamin D levels in human biological specimens has gained a high relevance over the last decades, essentially because low levels have been associated with several biological disorders. In fact, vitamin D deficiency has become a worldwide health concern covering all ages and genders. The storage of biofluids has to be considered for determination of vitamin D and metabolites in order to fully preserve matrices status. This study attempts to evaluate lyophilization of serum and plasma as a pre-processing step for sample storage prior to quantitative analysis of vitamin D and its main hydroxylated metabolites -25(OH)D, 24,25(OH)D and 1,25(OH)D. The protocol including sample lyophilization was characterized in terms of analytical features and compared to the same method, based on SPE-LC-MS/MS, without lyophilization. Sensitivity, precision and accuracy were not affected when we operated with lyophilized serum and plasma and results provided by a set of twenty-four serum samples from DEQAS (Vitamin D External Quality Assessment Scheme) were in agreement with reported concentrations for 25(OH)D and 1,25(OH)D. A stability study programmed for 9 months allowed ensuring that the concentration of vitamin D and metabolites in lyophilized serum and plasma stored at room temperature was not affected during this period. This research has demonstrated that the quantitation of target metabolites is not under the influence of lyophilization. Therefore, including lyophilization prior to analysis could reduce shipment and storage costs, avoid delays of sample processing, and increase the stability of the target analytes due to an effective quenching process.
在过去几十年中，测定人体生物样本中的维生素D水平变得至关重要，主要是因为低水平的维生素D与多种生物紊乱有关。事实上，维生素D缺乏已成为一个覆盖所有年龄和性别的全球健康问题。为了充分保持样本状态，在测定维生素D及其代谢物时必须考虑生物流体的储存。本研究试图评估血清和血浆的冻干作为样本储存的预处理步骤，以便在对维生素D及其主要羟基化代谢物——25(OH)D、24,25(OH)D和1,25(OH)D进行定量分析之前使用。对包括样本冻干在内的方案进行了分析特征表征，并与基于固相萃取-液相色谱-串联质谱法且未进行冻干的相同方法进行了比较。当我们使用冻干的血清和血浆进行操作时，灵敏度、精密度和准确度均未受到影响，并且来自DEQAS（维生素D外部质量评估计划）的一组24份血清样本所提供的结果与报告的25(OH)D和1,25(OH)D浓度一致。一项为期9个月的稳定性研究表明，室温下储存的冻干血清和血浆中维生素D及其代谢物的浓度在此期间未受影响。这项研究表明，目标代谢物的定量不受冻干的影响。因此，在分析前进行冻干可以降低运输和储存成本，避免样本处理延迟，并由于有效的淬灭过程提高目标分析物的稳定性。
