What is CE-SELEX? SELEX (Systematic Evolution of Ligands by EXponential Enrichment) is the standard process for aptamer development. It involves iterative rounds of selection and amplification to enrich nucleic acid sequences that bind tightly to a target molecule. Traditional SELEX often uses immobilization of the target on beads or filters, which can be slow (8-15 rounds) and may introduce bias by selecting for sequences that bind to the immobilization matrix itself. CE-SELEX uses Capillary Electrophoresis as the separation mechanism. The key principle is that when an aptamer binds to its target, it forms a complex with a different charge-to-size ratio, causing it to migrate at a different time (shifted peak) in the capillary compared to the unbound nucleic acid library. This complex can be isolated and collected with exquisite precision. Core Advantages of a CE-SELEX Screening Service A service provider offering CE-SELEX delivers significant benefits: Extreme Speed and Efficiency: Often requires only 2-4 rounds of selection to obtain high-affinity aptamers (nanomolar to picomolar Kd), compared to many more rounds in traditional SELEX. This translates to weeks or months of time saved. Solution-Phase Selection: The target is free in solution, eliminating immobilization bias. This allows for selection against targets in their native conformation and enables selection for small molecules and…
