Four-part differential leukocyte count using μflow cytometer

Abstract

This paper reports the four-part differential leukocyte count (DLC) of human blood using a MEMS microflow (flow) cytometer. It is achieved with a two-color laser-induced fluorescence (LIF) detection scheme. Four types of leukocytes including neutrophils, eosinophils, lymphocytes and monocytes are identified in blood samples, which are stained by fluorescein isothiocyanate (FITC) and propidium iodide (PI). The DLC results show good correlation with the count from a commercial hematology analyzer. The whole system is also implemented into a portable instrument for space application.

A microflow cytometer exploited for the immunological differentiation of leukocytes

“…Holmes et al demonstrated 3-part differential count in a microfluidic device detecting lymphocytes, monocytes, and neutrophils using AC impedance counting in combination with fluorescence detection (27). Fourpart differential blood count was demonstrated by Shi et al exploiting fluorescence staining with FITC and PI (28). They succeeded in differentiating lymphocytes, monocytes, neutrophils, and eosinophils with particle count rates around 10 Hz.…”

“…Differentiation of blood cells is considered as one of the most promising applications of microflow cytometers (9,20,(27)(28)(29). The prospects of high-throughput analysis and separation of blood cells using micro-devices were reviewed by Toner and Irimia (6).…”

A microfluidic blood-clogging valve for on-chip blood analysis

“…Blood thermal coagulation is a complex phenomenon that encompasses several processes including deformation and rupture of erythrocytes, protein denaturation, aggregation, and blood gelation [4]. Under a heating temperature of 45˚C, the normal disc-shaped erythrocytes starts to transform into the spherocytes, and substantial fragmentation of erythrocytes occurs after the heating temperature reaches 60˚C.…”

“…For an example, in our previous work, a leukocyte differential count using microfluidic cytometer was successfully demonstrated [4], but without a functional valve, sample preparations could not be incorporated on the device so that an automated chip would not be possible.…”

An integrated microfluidic system for counting of CD4+/CD8+ T lymphocytes

“…T lymphocyte counts were not yet performed. Recently, four differential leukocyte counts of human blood including neutrophils, eosinophils, lymphocytes, and monocytes by a microflow cytometer were reported (Shi et al 2010). A two-color laser-induced fluorescence detection scheme was adopted.…”