Continuous in vivo monitoring of small molecule biomarkers requires biosensors with reversibility, sensitivity in physiologically relevant ranges, and biological stability. Leveraging the real-time, label-free detection capability of surface plasmon resonance (SPR) technology, a molecularly responsive hydrogel film is introduced to enhance small molecule sensitivity. This advanced biosensing platform utilizes split-aptamer-cross-linked hydrogels (aptagels) engineered using 8-arm poly(ethylene glycol) macromers, capable of directly and reversibly detecting vancomycin. Investigation through SPR and optical waveguide mode, along with quartz crystal microbalance with dissipation (QCM-D) monitoring, reveals that the reversible formation of analyte-induced ternary molecular complexes leads to aptagel contraction and significant refractive index changes. Optimization of aptamer cross-link distribution and complementarity of split-aptamer pairs maximizes conformational changes of the aptagel, demonstrating a detection limit of 160-250 nM for vancomycin (6-9 fold improvement over monolayer counterpart) with a broad linear sensing range up to 1 mM. The aptagel maintains stability over 24 h in blood serum and 5 weeks in diluted blood plasma (mimicking interstitial fluid). This structurally responsive aptagel platform with superior stability and sensitivity offers promising avenues for continuous in vivo monitoring of small molecules.
- MeSH
- aptamery nukleotidové * chemie MeSH
- biosenzitivní techniky metody MeSH
- hydrogely * chemie MeSH
- lidé MeSH
- polyethylenglykoly chemie MeSH
- povrchová plasmonová rezonance * MeSH
- vankomycin * chemie krev MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- aptamery nukleotidové * MeSH
- hydrogely * MeSH
- polyethylenglykoly MeSH
- vankomycin * MeSH
