Aptamer Capture-SELEX Service refers to a specialized, outsourced process where a company or academic core facility performs the entire Capture-SELEX procedure to develop DNA or RNA aptamers for a client's specific target molecule. This is a crucial service for researchers and companies who need high-affinity, specific aptamers but lack the specialized equipment, expertise, or time to run the SELEX process in-house. Let's break down what this service entails. 1. What is Capture-SELEX? First, understand the standard SELEX (Systematic Evolution of Ligands by EXponential enrichment). It's an iterative process to select aptamers from a vast random oligonucleotide library (10^14 - 10^15 different sequences). Capture-SELEX is a specific variant designed primarily for small molecules or targets that are difficult to immobilize directly on a solid support without affecting their structure/function. The Key Difference: Instead of immobilizing the target itself, a short, complementary "capture strand" is immobilized on beads or a surface. The initial ssDNA library is designed with a region complementary to this capture strand. The target is free in solution. How it Works: The library is bound to the surface via the capture strand. The target molecule is introduced in solution. Only library sequences that fold into a structure capable of binding the target will undergo a conformational change. This binding event often weakens or…
