Selexkmdbio-Cellular Aptamer Screening Service Process

The specific screening process and sample requirements will vary according to the target characteristics and experimental requirements. The process of cell targeting aptamers screening is mainly based on SELEX technology and optimized using the aptamer cell selex method to meet the screening needs at the cellular level. A aptamer library containing a large number of random nucleic acid sequences (DNA or RNA, typically between 20 and 60 nucleotides in length) is constructed. Specific molecules on target cells or cell surfaces are used as targets (cell culture, purification, or labeling). The target cells are mixed with nucleic acid sequences from the aptamer library, and after incubation, the nucleic acid sequences bind to molecules on the surface of the target cells. The nucleic acid sequence that binds to the target is separated through filtration, centrifugation, magnetic bead separation, and other methods. The combined nucleic acid sequence is eluted and collected for the next round of screening. The secondary library is generated by amplifying the eluted nucleic acid sequence using PCR technology. The steps of binding, separation, elution, and amplification are repeated to gradually enrich high affinity aptamers. Through sequencing and sequence analysis, candidate aptamers were identified from the final enriched library. Simply put, SELEX technology is mainly to synthesize a single stranded oligonucleotide Library in vitro, and obtain nucleic acid aptamers with high affinity with target substances through repeated screening and amplification. Cell SELEX is to screen target substances such as cells and bacteria, separate and remove unbound suitable ligands by centrifugation and precipitation, alternate positive screening with negative screening of cells that do not express target proteins, and finally obtain aptamers. The specific process is shown in Figure 1.

Figure 1 cell targeting aptamers screening service process based on SELEX technology