The ArrayScan VTI, originally manufactured by Cellomics, is a modular high content screening (HCS) system designed for both cellular and sub-cellular analysis. This analysis is achieved by combining automated fluorescence microscopy with software that, via advanced informatics, conducts quantitative analysis of the images. Combining these aspects with robotics facilitates the fast and efficient screening of cell based assays.
The imaging system of the ArrayScan is built around microscope optics designed by Carl Zeiss. With operator control, the optical system is built to automate switching between objectives, which include a range of magnifications that are variable between instruments. Optics offer high resolution and sensitivity for all imaging requirements. A field of view of 1.3 x 1.3 mm is provided by the lowest 5X objective. Illumination of the samples is created by a white-light source, which can be easily changed for ease of use and maintenance. This light source is controlled by an adjustable shutter to prevent photobleaching of samples. The source creates a broad wavelength spectrum, ranging from 350 to 700 nm. These wavelengths can be isolated by a series of filters, which are included on a 10 position wheel and a 5 position turret for providing excitation and dichroic/emission cubes, respectively. This range allows the operator to image a variety of dyes, covering blues, greens, and reds (orange-red, deep, and long).
For the capturing of images, the instrument comes equipped with a scientific-grade digital camera. This CCD camera captures high-resolution images of the magnifications provided by the microscope components. The instrument is designed to autofocus on each microplate well in less than a second, ensuring not only high quality and in-focus images, but also the maintenance of high throughput capabilities.