A novel approach to the photochemical UV-C activation of PAA-coated Fe₃O₄ nanoparticles for oriented APTES functionalisation with free surface-amino groups

• Fe₃O₄ nanoparticles with polyhedral and cubic morphologies were synthesised by thermal decomposition. • A novel method was used for surface modification of Fe 3 O 4 @PAA MNPs with APTES. • ATR-FTIR and XPS confirmed successful ligand attachment; zeta potential shifted from negative to positive. • RNA extraction efficiency of modified nanoparticles was comparable to SiO₂-coated MNPs commonly used in commercial-like kits. Fe₃O₄ MNPs with polyhedral ( P1 ) and cubic ( K1 ) morphologies, prepared