Baillargeon Keith R, Brooks Jessica C, Miljanic Philip R, Mace Charles R
Department of Chemistry and Laboratory for Living Devices, Tufts University, Medford, Massachusetts 02155, United States.
ACS Meas Sci Au. 2022 Feb 16;2(1):31-38. doi: 10.1021/acsmeasuresciau.1c00031. Epub 2021 Sep 17.
Dried blood spot (DBS) cards perform many functions for sampling blood that is intended for subsequent laboratory analysis, which include: (i) obviating the need for a phlebotomist by using fingersticks, (ii) enhancing the stability of analytes at ambient or elevated environmental conditions, and (iii) simplifying the transportation of samples without a cold chain. However, a significant drawback of standard DBS cards is the potential for sampling bias due to unrestricted filling caused by the hematocrit of blood, which often limits quantitative or reproducible measurements. Alternative microsampling technologies have minimized or eliminated this bias by restricting blood distribution, but these approaches deviate from clinical protocols and present a barrier to broad adoption. Herein, we describe a patterned dried blood spot (pDBS) card that uses wax barriers to control the flow and restrict the distribution of blood to provide enhanced sampling. These patterned cards reproducibly fill four replicate extraction zones independent of the hematocrit effect. We demonstrate a 3-fold improvement in accuracy for the quantitation of hemoglobin using pDBS cards compared to unpatterned cards. Patterned cards also facilitate the near quantitative recovery (ca. 95%) of sodium with no evidence of a statistically significant difference between dried and liquid blood samples. Similarly, the recovery of select amino acids was conserved in comparison to a recent report with improved intercard precision. We anticipate that this approach presents a viable method for preparing and storing samples of blood in limited resource settings while maintaining current clinical protocols for processing and analyzing dried blood spots.
干血斑（DBS）卡片在采集用于后续实验室分析的血液样本方面具有多种功能，包括：（i）通过手指采血避免了对采血技师的需求；（ii）在环境温度或高温条件下提高了分析物的稳定性；（iii）简化了无需冷链的样本运输。然而，标准DBS卡片的一个显著缺点是，由于血液的血细胞比容导致不受限制的填充，可能存在采样偏差，这通常会限制定量或可重复测量。替代微采样技术通过限制血液分布将这种偏差最小化或消除，但这些方法偏离了临床方案，成为广泛采用的障碍。在此，我们描述了一种图案化干血斑（pDBS）卡片，它使用蜡屏障来控制血液流动并限制血液分布，以提供更好的采样效果。这些图案化卡片可重复地填充四个独立于血细胞比容效应的重复提取区域。与无图案卡片相比，我们证明使用pDBS卡片定量血红蛋白的准确性提高了3倍。图案化卡片还促进了钠的近定量回收（约95%），干血样和液体血样之间没有统计学上显著差异的证据。同样，与最近一份报告相比，选定氨基酸的回收率得以保持，卡片间精密度有所提高。我们预计，这种方法为在资源有限的环境中制备和储存血液样本提供了一种可行的方法，同时保持了当前处理和分析干血斑的临床方案。
