Fabrication of bio-based nanomicrospheres with a 3D porous structure for efficient matrine adsorption using...

Coptis herbs and Sophora moorcroftiana are primary sources of alkaloids with significant application value, including matrine (MT). Currently, in the separation and purification methods of alkaloids, while the adsorption method is straightforward and practical, most adsorption materials are non-renewable synthetic compounds, which can lead to environmental pollution. Therefore, we utilized TEMPO-modified natural biomass macromolecular cellulose nanocrystals (TOCN) and environmentally degradable dendritic mesoporous organosilica nanoparticles (DMONs) as raw materials, employing a surface assembly technique to coat negatively charged cellulose onto the surface of DMONs. This process led to the synthesis of TOCN@DMONs, an effective and eco-friendly bio-based composite material. The TOCN@DMONs were subjected to various analytical techniques, which unequivocally confirmed its successful synthesis and demonstrated its impeccable physical and chemical properties. The prepared TOCN@DMONs exhibited nanoscale dimensions, abundant pore structure, and excellent thermal stability. The adsorption process of MT on TOCN@DMONs followed the pseudo-second-order kinetics and Langmuir isotherm model. Thermodynamic parameters indicated that the adsorption process was spontaneous, endothermic, and involved weak chemical bonds. These findings indicate that TOCN@DMONs, as a green and highly efficient adsorbent, has a good application potential for the concentration of total alkaloids and the purification of MT from Coptis herbs and Sophora moorcroftiana extracts.