1：Experimental Design and Method Selection:

The study utilized a microfluidic emulsification process to create water-based droplets that were stretched into anisotropic shapes and then converted into particles via photopolymerization. Birefringence was achieved by aligning cellulose nanocrystals (CNCs) within the microparticles during droplet stretching, and magnetic responsiveness was introduced by adding superparamagnetic nanoparticles (SPIONs) to the initial droplet template.

2：Sample Selection and Data Sources:

Aqueous suspensions containing CNCs, SPIONs, monomers, and initiator were used as the inner phase for droplet formation. Hexadecane with the surfactant PGPR was used as the outer oil phase.

3：List of Experimental Equipment and Materials:

Microfluidic devices built from glass capillaries, syringe pumps for fluid injection, PTFE tubes for droplet elongation, and a UV light source for photopolymerization were used. Materials included acrylamide, N,N′-methylenebisacrylamide, hydroxy-4′-(2-hydroxyethoxy)-2-methylpropiophenone (Irgacure 2959), hexadecane, trimethoxy(octadecyl)silane (ODTMS), butylamine, PGPR, SPIONs (type EMG 605), and CNCs.

4：Experimental Procedures and Operational Workflow:

The microfluidic device was operated under flow-focusing dripping conditions to create monodisperse droplets. The droplets were elongated in a small-diameter tube to align CNCs and then polymerized under UV light. The resulting microparticles were collected, washed, and stored in deionized water.

5：Data Analysis Methods:

The alignment of CNCs and the response of microparticles to magnetic fields were assessed using optical microscopy under cross-polarizers. The viscosity of suspending fluids was measured by steady-state shear rheology.