DNA Immobilization

Abstract

Immobilized DNA is used for various purposes, starting with the development of DNA chips and microarrays, and reaching to methods for gene delivery and DNA‐based vaccines. The broad application range for all of these DNA‐based systems can still be found in the medical area (e.g. diagnostics and therapeutics, combined ‘theranostics’). Furthermore, in particular, DNA sensors are described to ensure food safety. Hence, strategies for DNA immobilization are described in this article, with a strong focus on immobilization chemistry. Various immobilization techniques (e.g. via physical adsorption, covalent, affinity binding, and matrix entrapment/encapsulation) are already well established. The ‘top‐down’ techniques can be distinguished from the ‘bottom‐up’ techniques that started at the beginning of DNA chip development. Suitable synthetic and artificial DNA structures (e.g. DNA origami) are developed and become adapted to existing DNA platforms. Surfaces used for DNA immobilization comprise carbonaceous materials, silica and silicon surfaces, gold, and metal surfaces, in addition to (bio)polymers. More recently, nanostructures for drug and gene delivery via liposomes and cationic polymers are on focus to generate therapeutic devices and vaccines. Overall, the main aim of this article is to provide an overview of the methods currently used for DNA immobilization regarding the variety of DNA and surface structures for different applications.