Peristaltic MHD flow of Casson hybrid nanofluids (Ta–Cu/Blood) in a non-uniform asymmetric microchannel: Influence of electro osmosis, shape factor and biomedical implications

• Combined effects of peristalsis, electroosmosis, and MHD are investigated. • Flow of Casson hybrid nanofluid in an asymmetric microchannel is analysed. • The Homotopy Perturbation Method is used for accurate analytical solutions. • The impact of nanoparticle fractions on the flow characteristics is described. • Study provides insights for drug delivery and biomedical micro-pump design. This study examines the electroosmotic peristaltic transport of a Casson hybrid nanofluid ( T a − C u / b l o o d ) through an asymmetric microchannel subjected to combined magnetic and electric fields. The governing nonlinear equations are simplified using the long-wavelength and low-Reynolds-number assumptions and linearized via the Debye–Hückel approximation. Analytical expressions for velocity and temperature are derived using the homotopy perturbation method. The velocity profile in a channel experiences an expansion near the left wall and a contraction near the right wall as the Helmholtz-Smoluchowski parameter increases.The concentration of Tantalum nanoparticles increases thermal conductivity, lowers wall temperature, and enhances heat dispersion. As the Casson fluid parameter increases, the pressure rise in the retrograde region decreases, whereas it intensifies in the augmented region. The thermal Grashof number increases, leading to a larger bolus size as stronger buoyancy forces promote fluid motion. Adding 2 % copper nanoparticles increases heat transfer at the right wall by 4.04 %. Laminar-shaped nanoparticles result in a 3.24 % higher heat transfer at the right wall compared to spherical nanoparticles. This model uniquely integrates Casson non-Newtonian effects, hybrid nanoparticle thermophysics, and electroosmotic interactions in an asymmetric configuration, offering a novel framework for the design of microvascular therapies, lab-on-chip systems, and targeted biomedical devices.