In Vitro Selection of a DNA Aptamer Targeting Degraded Protein Fragments for Biosensing

Protein biomarkers often exist as degradation fragments in biological samples, and affinity agents derived using a purified protein may not recognize them, limiting their value for clinical diagnosis. Herein, we present a method to overcome this issue, by selecting aptamers against a degraded form of the toxin B protein, which is a marker for diagnosing toxigenic Clostridium difficile infections. This approach has led to isolation of a DNA …