Label-Free Sensing and Classification of Old Stored Blood.

Transfusion is crucial in surgical operation and anemia treatment. However, several hemorheological properties of blood are adversely altered during blood storage. After transfusion, these adverse alterations are related with decrease of oxygen and ion transport in blood circulation, which increase the mortality of transfused patients. Therefore, accurate sensing of whether a blood supply is still viable for transfusion or not is extremely important. In this study, a H-shaped microfluidic device and digital in-line holographic microscopy were employed to measure temporal variations of blood viscosity and the optical focusing property of erythrocytes during blood storage. Stored rat blood samples separately preserved in citrate phosphate dextrose adenine-1 (CPDA-1) and ethylenediaminetetraacetic acid (EDTA) underwent considerable changes in their biophysical parameters after 2 weeks. Compared with EDTA, CPDA-1 preserves the hemorheological properties of stored blood more effectively. We propose new criteria for depository period of stored blood and indexes, such as viscosity and focal length of erythrocytes, to determine its appropriateness for transfusion. These criteria and indexes can be effectively used for high-throughput prescreening to reduce the risk of transfusion of aged blood or diagnose hematological diseases.