Improved mechanical performance and enzymatic stability of crosslinked dry amniotic membrane by spraying

Abstract

Human amniotic membrane (AM), a valuable natural biomaterial, is increasingly used in clinical applications. However, its limited mechanical strength and rapid degradation restrict broader use. To address these limitations, we developed a spray-applied crosslinking method for dry AM. A spray delivery of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) with N-hydroxysuccinimide (NHS), combined with a hydrogen-bond-supplementing solution (oxygen-containing compounds), produced a crosslinked dry AM with improved mechanical strength and enhanced resistance to enzymatic degradation in vitro. The EDC/NHS chemistry promoted the formation of covalent bonds within the collagen network, increasing tensile strength and enzymatic stability, while the hydrogen-bond supplement preserved the membrane’s native flexibility after rehydration. The maximum uniaxial tensile fracture stress of the crosslinked AM increased by 156.1%, and the weight loss ratio of enzymatic degradation decreased from 100% to 63.6%. These results indicated that the spray crosslinking protocol yielde a mechanically robust, enzymatically stabilized AM without compromising flexibility, and might expand the membrane’s clinical applicability.

Graphical Abstract

Keywords

Dry amniotic membrane / Spray-crosslinked / EDC/NHS crosslinking system / Mechanical strength / Anti-enzymatic degradation

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Funding

National Natural Science Foundation of China(32271396)

Cultivating Plan Program for the Leader in Science and Technology of Yunnan Province(gpyc20240049)

RIGHTS & PERMISSIONS

The Author(s)