Comparative study of green chemical separation techniques for cellulose-based microcapsules from bamboo parenchyma...

Microcapsules are recognized for their broad applications in controlled drug release, smart textiles, and self-lubrication. However, current synthesis methods are often complex and rely on toxic substances, which limit their environmental sustainability and practical usability. This situation highlights the need for simpler, eco-friendly production methods with sustainable materials. Bamboo parenchyma cells (PCs), due to their hollow, microcapsule-like structure, represent underutilized resources for these applications. Nevertheless, their isolation and use have remained largely unexplored. In this study, the identified gap is addressed by developing a green chemistry approach to isolate PCs using chemical reagents such as NaClO₂, H₂O₂/CH₃COOH, and NaOH-Na₂SO₃-NaClO₂. The effects of different solvent systems and processing conditions on the physical and chemical properties of the PCs were evaluated. The results indicate that these mild chemical separation methods effectively preserve the microcapsule-like structure of the PCs, with varying porosity (specific surface area of 0.194-3.679 m²/g) and cellulose content (58.0 %-74.3 %), depending on the method used. Among the tested systems, NaOH-Na₂SO₃-NaClO₂ yielded PCs with the highest porosity at the lowest cost (0.37 yuan/g). These findings demonstrate the potential of PCs as sustainable alternatives for applications such as controlled drug release and provide key insights into optimizing separation techniques for broader industrial use.