This study presents an enhanced paper‐based analytical device (PAD) for forward and reverse group blood typing. The proposed PAD uses a novel methodology, which provides highly reliable results on a fully cellulose based device. The PAD was printed on different cellulose substrates. These substrates were made of different cellulose fibers (sisal and eucalyptus), different grammages, refining steps, and wet additive content. Best parameters were chosen to achieve high reliability on both forward and reverse blood typing. The substrates were patterned with five hydrophilic channels and two hydrophobic areas. For reverse blood typing, the hemoagglutination reaction took place on the hydrophobic surface of the paper before being transferred to the paper web, where together with the forward blood typing tests were all washed with saline solution to read the results by elution. This device allows direct read‐out of results; the stains show were agglutination happens. Different blood types were in full agreement between the reverse and forward method and in agreement with traditional methods. The time and simplicity of this methodology confirmed its utility.

中文翻译：

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增强型完全基于纤维素的正向和反向血型分析。

本研究提出了一种用于正向和反向血型分型的增强型纸质分析设备 (PAD)。所提出的 PAD 使用一种新颖的方法，它在完全基于纤维素的设备上提供高度可靠的结果。PAD 印刷在不同的纤维素基材上。这些基材由不同的纤维素纤维（剑麻和桉树）、不同的克重、精炼步骤和湿添加剂含量制成。选择最佳参数以实现正向和反向血型的高可靠性。基板上有五个亲水通道和两个疏水区域。对于反向血型，血凝反应发生在纸的疏水表面，然后转移到纸幅上，其中与前向血型测试一起用盐水溶液洗涤以通过洗脱读取结果。该设备允许直接读出结果；污渍显示发生凝集。不同血型在反向和正向方法之间完全一致，与传统方法一致。这种方法的时间和简单性证实了它的实用性。