Size-selective detection in integrated optical interferometric biosensors.

We present a new size-selective detection method for integrated optical interferometric biosensors that can strongly enhance their performance. We demonstrate that by launching multiple wavelengths into a Young interferometer waveguide sensor it is feasible to derive refractive index changes from different regions above the waveguide surface, enabling one to distinguish between bound particles (e.g.

Clinical evaluation of a simple image cytometer for CD4 enumeration on HIV-infected patients.

Background: Affordable, easy-to-use, and reliable CD4(+) T lymphocyte enumeration systems are needed in resource-constrained settings to monitor HIV.

Methods: A simple image cytometer was used to count fluorescently labeled CD4(+) T and CD8(+) T lymphocytes from CD3 immunomagnetically selected cells on blood specimens of 460 HIV-1-infected patients in Siriraj Hospital, Bangkok, Thailand. Results were compared with flow cytometry (FCM).

CD4 and CD8 enumeration for HIV monitoring in resource-constrained settings.

Background: We developed a volumetric single platform image cytometer (SP ICM) that is dedicated to count CD4(+) and CD8(+) T lymphocytes for HIV monitoring in resource-constrained settings. The instrument was designed to be low-cost, yet reliable, easy-to-use, and robust.

Methods: Whole blood is incubated with CD3-magnetic nanoparticles, CD4-phycoerythrin (PE), and CD8-peridinin-chlorophyll-protein complex (PerCP).

An ultrasensitive young interferometer handheld sensor for rapid virus detection.

Future viral outbreaks are a major threat to societal and economic development throughout the world. A rapid, sensitive and easy-to-use test for viral infections is essential to prevent and control such viral pandemics. Furthermore, a compact, portable device is potentially very useful in remote or developing regions without easy access to sophisticated laboratory facilities.

CD4+ T lymphocytes enumeration by an easy-to-use single platform image cytometer for HIV monitoring in resource-constrained settings.

Background: HIV monitoring in resource-constrained settings demands affordable and reliable CD4(+) T lymphocytes enumeration methods. We developed a simple single platform image cytometer (SP ICM), which is a dedicated volumetric CD4(+) T lymphocytes enumeration system that uses immunomagnetic and immunofluorescent technologies. The instrument was designed to be a low-cost, yet reliable and robust one.