Nucleic acid aptamers: new methods for selection, target validation, molecular diagnostics and therapeutics.

Nucleic acid aptamers, often referred to as "chemical antibodies," are versatile, specific, and easily modifiable functional nucleic acids. There is a growing focus on new methods for the selection and target validation of aptamers, with the aim of expanding their biomedical applications in molecular diagnostics and therapeutics, which is currently a research hotspot. This review is composed of eight sections. In the first section, we briefly introduce aptamers and review their development in molecular diagnostics and therapeutics. The "Advantages of aptamers in molecular diagnosis and therapeutics" section summarizes and discusses the advantages of aptamers in these fields. The "New methods for screening aptamers" section presents and discusses nucleic acid aptamer screening methods, including both classical and novel approaches. In the "New methods for target validation" section, we explore new methods for target validation, covering aptamer structure validation, target recognition validation, and aptamer-target interaction validation. The "New methods for molecular diagnostics" section summarizes and discusses recent applications of aptamers in molecular diagnostics, particularly focusing on new mechanisms and detection strategies as well as their applications in various diseases. The "New methods for molecular therapeutics" section summarizes and discusses recent applications of aptamers in molecular therapeutics, emphasizing new mechanisms and aptamer-based therapy strategies, along with their therapeutic applications in different diseases. The "Challenges and future perspectives of nucleic acid aptamers" section addresses the challenges and future perspectives of aptamers in disease diagnosis and treatment. Finally, the "Conclusion" section shares our views on the future directions of aptamers in clinical disease molecular diagnostics and therapeutics.