Microfluidic Cartridges for Automated, Point-of-Care Blood Cell Counting

Abstract

Disposable, low-cost microfluidic cartridges for automated blood cell counting applications are presented in this article. The need for point-of-care medical diagnostic tools is evident, particularly in low-resource and rural settings, and a full blood count is often the first step in patient diagnosis. Total white and red blood cell counts have been implemented toward a full blood count, using microfluidic cartridges with automated sample introduction and processing steps for visual microscopy cell counting to be performed. The functional steps within the microfluidic cartridge as well as the surrounding instrumentation required to control and test the cartridges in an automated fashion are described. The results recorded from 10 white blood cell and 10 red blood cell counting cartridges are presented and compare well with the results obtained from the accepted gold-standard flow cytometry method performed at pathology laboratories. Comparisons were also made using manual methods of blood cell counting using a hemocytometer, as well as a commercially available point-of-care white blood cell counting system. The functionality of the blood cell counting microfluidic cartridges can be extended to platelet counting and potential hemoglobin analysis, toward the implementation of an automated, point-of-care full blood count.

Advances in Microfluidics for Single Red Blood Cell Analysis

“…Disposable and low-cost microfluidic platforms for the automated blood cell counts are desirable in rural and remote regions. A comparison of cell counting efficiencies between an automated microfluidic platform, a hemocytometer, and conventional techniques such as the golden standard of flow cytometry have indicated a good correlation [277]. Another work involves the integration of a microfluidic cytometry with on-chip optical systems to detect cells in biological samples [278].…”

Current Status of Clinical Application of Point-of-Care Testing

“…Some studies have investigated portable instruments using newer technology, such as single-sample cuvettes and image analysis, microfluidic cartridges, and the lab-ona-chip/micro total analysis system platform, which provides complete blood cell count tests including 3-part differential white blood cells, red blood cells, platelet count, and hemoglobin for rapid diagnosis in resource-poor environments. [3][4][5] A rapid complete blood cell count and differential blood panel can help clinicians determine whether a patient is suffering from a viral or bacterial infection and whether he or she requires admission and antibiotics.…”

Automated passive serial dilution microfluidic chip for calcium quantification based on the Arsenazo III method

“…The cartridge meters and mixes the fluids in a chamber, which is then analyzed. 30,31 While this method can provide exact metering in a valve-less system, the hardware's complexity and cost are higher at the expense of a simple chip design. Hence in this study, we demonstrate a passive resistive network microfluidic device with a simple design for calcium analysis in urine that would be easy to implement in a smart toilet using only the local pressure and water source and does not require any valves or metering for precise control over mixing ratios.…”