Chip could lead to inexpensive portable cell-screening devices

‘HIV is diagnosed based on counting CD4 cells,’ said Tony Jun Huang, associate professor of engineering science and mechanics at Penn State University. ‘Ninety per cent of the diagnoses are done using flow cytometry.’

According to a statement, Huang and his colleagues designed a mass-producible device that can focus particles or cells in a single stream and performs three different optical assessments for each cell. They believe that the device represents a major step toward low-cost flow cytometry chips for clinical diagnosis in hospitals, clinics and in the field.

‘The full potential of flow cytometry as a clinical diagnostic tool has yet to be realised and is still in a process of continuous and rapid development,’ the team said in a recent issue of Biomicrofluidics. ‘Its current high cost, bulky size, mechanical complexity and need for highly trained personnel have limited the utility of this technique.’

Flow cytometry is said to typically look at cells in three ways using optical sensors. Flow cytometers use a tightly focused laser light to illuminate focused cells and to produce three optical signals from each cell.