logo

Video encyclopedia

Biosensor

1:52

What is a biosensor?

2:00

Biosensors

1:51

What are biosensors, an animated introduction

1:47

Keep a close watch on patients with the Philips wearable biosensor

3:26

Biosensor: An overview

A DNA microarray is a collection of microscopic DNA spots attached to a solid surface. Scientists use DNA microarrays to measure the expression levels of large numbers of genes simultaneously or to genotype multiple regions of a genome. Each DNA spot contains picomoles of a specific DNA sequence, known as probes. These can be a short section of a gene or other DNA element that are used to hybridize a cDNA or cRNA sample under high-stringency conditions. Probe-target hybridization is usually detected and quantified by detection of fluorophore-, silver-, or chemiluminescence-labeled targets to determine relative abundance of nucleic acid sequences in the target. The original nucleic acid arrays were macro arrays approximately 9 cm × 12 cm and the first computerized image based analysis was published in 1981.
    • Principle 

    • Uses and types 

    • Microarrays and bioinformatics 

    • Alternative technologies 

    • Glossary