Rapid selection of aptamers based on protein microarray

Area of Science:

• Biotechnology
• Molecular Biology
• Biochemistry

Background:

• Aptamers are short DNA or RNA sequences that bind to specific targets.
• Traditional aptamer screening methods like SELEX can be time-consuming and labor-intensive.
• Efficient screening methods are needed to develop aptamer-based diagnostics and therapeutics.

Purpose of the Study:

• To develop and validate a novel, efficient aptamer screening method named Microarray-SELEX.
• To demonstrate the capability of Microarray-SELEX for identifying specific aptamers against lactoferrin.

Main Methods:

• A protein microarray was created by immobilizing target (lactoferrin) and negative proteins.
• A single-stranded DNA (ssDNA) library was incubated with the microarray, first with negative proteins, then with the target protein.
• The aptamer screening process was monitored in real-time using a fluorescent microarray scanner.

Main Results:

• The Microarray-SELEX method successfully identified five specific aptamers (YFL-1, YFL-4, YFL-5, YFL-6, YFL-7) for lactoferrin in just six rounds.
• The obtained aptamers demonstrated high specificity in the presence of competing negative proteins.
• The aptamers exhibited equilibrium dissociation constants (Kd) in the nanomolar range, indicating high binding affinity.

Conclusions:

• Microarray-SELEX is a rapid, sensitive, and efficient method for aptamer screening.
• This technique offers a streamlined approach for aptamer discovery compared to conventional methods.
• The developed aptamers show potential for applications in diagnostics or therapeutics targeting lactoferrin.