Aptamers—short, single-stranded DNA or RNA oligonucleotides that fold into target-binding structures—are attractive tools for therapeutics, diagnostics, and biosensing. But one limitation shows up again and again in real-world use: stability. In biological fluids, aptamers can be degraded by nucleases, lose their functional conformation, or get cleared rapidly due to small size. “Enhancing aptamer stability” therefore means engineering aptamers to retain integrity and function under the conditions they must actually operate in—serum, cells, elevated temperatures, long storage, or repeated assay cycles. This article explains the major stability failure modes and the best-established enhancement strategies—organized the way practitioners typically make design decisions. 1) What “Aptamer Stability” Really Means (It’s Not One Thing) When people say “aptamer stability,” they often blend multiple properties: Nuclease stability (biostability): resistance to DNases/RNases in serum, plasma, and tissues. Structural/conformational stability: ability to keep the correct fold that binds the target (especially under ionic changes, crowding, or temperature shifts). Thermal stability: higher melting temperature (Tₘ) and robust folding across a wider temperature range. Circulation stability (pharmacokinetic stability): staying in the bloodstream long enough to matter—often limited by renal filtration for small oligos. Functional stability: maintaining binding affinity/specificity after modifications, storage, repeated use, or immobilization. A…
Peptide therapeutics (sometimes called “peptide therapy” in popular health content) refers to the design and development of peptide-based medicines—short chains of amino acids engineered to treat, manage, or modify disease. Unlike vague wellness claims, therapeutic peptides in drug development are defined, characterized, and manufactured as medicinal products with measurable pharmacology, safety testing, and quality controls. Peptides occupy a practical middle ground between small molecules and large biologics: they can be highly selective like proteins while remaining more modular and tunable through chemical design. What Exactly Are Peptides in Medicine? A peptide is a molecule made of amino acids linked by peptide bonds. In therapeutics, peptides are often sized to be large enough to recognize biological targets precisely, but small enough to be synthesized and optimized with medicinal chemistry approaches. Reviews describe peptide drugs as a distinct class with strengths such as specificity and structural versatility, alongside known limitations such as enzymatic breakdown and delivery barriers. Why Peptide Drugs Matter: The Biological “Sweet Spot” Peptide therapeutics are valuable because they can: Bind targets with high specificity (reducing off-target effects compared with many small molecules). Mimic or modulate natural signaling pathways, because many hormones and signaling mediators are peptide-like.…
