Boosting the mechanical and biological performance of decellularized plant-derived scaffolds via alkali-mediated...

Tissue engineering aims to develop functional biomimetic constructs to restore, maintain, or replace damaged tissues. Recently, decellularized plant-based scaffolds have emerged as sustainable, cost-effective, and ethically favorable alternatives to animal-derived matrices due to their preserved three-dimensional architecture. Despite their many advantages, the clinical translation of plant-derived scaffolds remains limited by two major challenges: insufficient mechanical strength and poor cell-material interactions. Here, we introduce alkali-mediated mercerization as a simple, one-step post-decellularization modification strategy to simultaneously enhance the mechanical properties and cellular response of plant-derived scaffolds. First, spinach leaves were chemically decellularized and subsequently subjected to sodium hydroxide treatments with varying concentrations and exposure durations. The effects of mercerization were then evaluated through morphological, chemical, structural, physicochemical, mechanical, and biological characterizations. Mercerization was supported by evidence of cellulose structural and crystalline reorganization, along with morphological densification of the fibrillar network. These modifications resulted in a pronounced enhancement in surface hydrophilicity, with water contact angles decreasing to 0° within seconds, indicating rapid surface hydration. The physicochemical improvements translated into substantial mechanical reinforcement. The ultimate tensile strength increased from 0.62 ± 0.06 MPa in untreated scaffolds to 3.11 ± 0.20 MPa in mercerized scaffolds (∼5-fold increase), while the elastic modulus increased from 38.53 ± 17.73 MPa to 110.00 ± 37.20 MPa (∼3-fold increase), demonstrating significantly improved stiffness and load-bearing capacity. Finally, biological evaluations showed that all alkali-treated scaffolds were non-cytotoxic. Importantly, mercerized scaffolds supported a more favorable cellular response, as indicated by up to a 3.0-fold increase in metabolic activity after 7 d compared to untreated spinach controls, together with improved cellular coverage. Overall, this study provides a comprehensive and quantitative demonstration that alkali-mediated mercerization enables simultaneous mechanical strengthening and improved cellular response in plant-derived scaffolds through a simple, cost-effective, and sustainable post-processing modification strategy, highlighting its translational potential for tissue engineering applications.