A Comprehensive In Vitro Approach for Assessing the Physiological Degradation of Medical Implants: The Silkothane Arteriovenous Graft Case Study
- 1Department of Chemistry Materials and Chemical Engineering “G. Natta” Politecnico di Milano Milan Italy
- 2Dialybrid S.r.l. Cantù Italy
Abstract
Current in vitro degradation methodologies for absorbable medical devices often employ nonphysiological enzyme concentrations or bacterial proteases, limiting their predictive value for in vivo performance. Here, a framework for assessing protein‐based device degradation is developed using a three‐layered silk fibroin/polyurethane (Silkothane) Arteriovenous Graft (SAG) as a case study. A mixture of human enzymes targeting silk fibroin, the degradable component of the graft, is selected and their activities balanced by adjusting concentrations, enabling reliable tracking of activity decay and determination of a buffer‐refresh frequency. The enzyme mixture, applied at physiological concentrations, is then used to digest the grafts for up to 26 weeks, with undigested samples serving as controls. Grafts are assessed for morphology, mass loss, mechanical properties, and molecular weight, while buffers are evaluated for morphology, cytotoxicity, and molecular weight. Mass loss measurements are corrected for enzyme adsorption onto the graft, revealing actual enzymatic degradation rates. Results demonstrate minimal degradation with preserved structural integrity, consistent with surface erosion and in qualitative agreement with published and unpublished in vivo data. This framework provides a reproducible, physiologically relevant methodology for assessing protein‐based absorbable devices, in a first step toward bridging regulatory requirements and biological relevance while reducing reliance on animal testing.
Related
- Spatial Inhomogeneity of Thermal Degradation of Semi-Crystalline Polymers
- Amorphous Cu-FeOOH Clusters on Oxygen-Deficient Fe-Doped BiOCl Nanoflowers for Efficient Photo-Fenton Degradation of Levofloxacin
- Nitrogen-Stabilized Fe–Co Nanoclusters Supported on Mushroom-Residue-Derived Porous Carbon for Peroxymonosulfate Activation Toward Sulfadiazine Degradation
- Machine Learning-Assisted Analysis of Chloride-Enhanced BiOCl/DSA Anode for Synergistic Denitrification and Tetracycline Degradation: Performance, Mechanisms, and Product Regulation
- Degradation and Stabilization of Inverted Perovskite Solar Cells
BibTeX
@article{oldani2026comprehensive,
title = {{A Comprehensive In Vitro Approach for Assessing the Physiological Degradation of Medical Implants: The Silkothane Arteriovenous Graft Case Study}},
author = {Cristina Oldani and Alice Caldiroli and Federica Barzaghi and Nina Bono and Gabriele Candiani and Stefania Adele Riboldi},
journal = {Advanced NanoBiomed Research},
year = {2026},
month = nov,
doi = {10.1002/anbr.70156},
url = {https://doi.org/10.1002/anbr.70156},
note = {CC BY},
}
RIS
TY - JOUR
TI - A Comprehensive In Vitro Approach for Assessing the Physiological Degradation of Medical Implants: The Silkothane Arteriovenous Graft Case Study
AU - Cristina Oldani
AU - Alice Caldiroli
AU - Federica Barzaghi
AU - Nina Bono
AU - Gabriele Candiani
AU - Stefania Adele Riboldi
PY - 2026
DA - 2026/11/02
JO - Advanced NanoBiomed Research
DO - 10.1002/anbr.70156
UR - https://doi.org/10.1002/anbr.70156
AB - Current in vitro degradation methodologies for absorbable medical devices often employ nonphysiological enzyme concentrations or bacterial proteases, limiting their predictive value for in vivo performance. Here, a framework for assessing protein‐based device degradation is developed using a three‐layered silk fibroin/polyurethane (Silkothane) Arteriovenous Graft (SAG) as a case study. A mixture of human enzymes targeting silk fibroin, the degradable component of the graft, is selected and their activities balanced by adjusting concentrations, enabling reliable tracking of activity decay and determination of a buffer‐refresh frequency. The enzyme mixture, applied at physiological concentrations, is then used to digest the grafts for up to 26 weeks, with undigested samples serving as controls. Grafts are assessed for morphology, mass loss, mechanical properties, and molecular weight, while buffers are evaluated for morphology, cytotoxicity, and molecular weight. Mass loss measurements are corrected for enzyme adsorption onto the graft, revealing actual enzymatic degradation rates. Results demonstrate minimal degradation with preserved structural integrity, consistent with surface erosion and in qualitative agreement with published and unpublished in vivo data. This framework provides a reproducible, physiologically relevant methodology for assessing protein‐based absorbable devices, in a first step toward bridging regulatory requirements and biological relevance while reducing reliance on animal testing.
SN - 2699-9307
ER -