Switches Based on Aptamers

An aptamer is a short, single-stranded DNA or RNA sequence. These molecules typically demonstrate a high affinity to a multitude of molecules from proteins to cells [111]. The sensitivity and selectively with which aptamers bind make them promising options in diagnostic and therapeutic applications [111, 112]. 

Because aptamers experience reversible denaturation and regeneration, their use is particularly attractive in reusable sensing technologies [113], Many of the potential uses for aptamers require that these molecules are immobilized on the surface. 

This requirement compHcates their use because the retaining method employed must sustain the high binding affinity aptamers demonstrate in solution. Another challenge concerns the need to acquire a flexible, ordered receptor molecule while maintaining the appropriate aptamer folding that induces binding. 

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