Modeling the drug delivery mechanism via peristaltic transport of the Johnson-Segalman fluid influenced by heat/mass transfer and chemical reactions

Peristalsis is essential for biological and industrial applications, but little is understood about how it operates in non-Newtonian fluids. The current study looks into the peristaltic flow of a non-Newtonian, viscous, incompressible, and electrically conducting Johnson-Segalman fluid in an asymmetric channel, taking into account the effects of heat transfer, mass transfer, and chemical reactions in order to model and improve drug delivery mechanisms. The Johnson-Segalman fluid most appropriately represents a mucus-like viscoelastic polymer/surfactant drug carrier used to transport a reactive therapeutic solute under peristaltic motion. In other words, polymeric micelles are the drug carrier that the Johnson-Segalman fluid represents in the present model. At the same time, the dissolved drug is modeled through the mass-transfer equation, and the chemical reaction term accounts for processes such as drug absorption, degradation, or biochemical interaction within the physiological environment. The perturbation approach is used to solve the nonlinear governing equations under the assumptions of long wavelength and low Reynolds number. Calculations are performed on the velocity field, stream function, pressure gradient, and pressure rise. Additionally, the trapping phenomenon has been investigated. Finally, plots and discussion are created to demonstrate how various emergent parameters impact the relevant physical quantities. The results reveal that the influence of the Weissenberg number [Formula: see text] on the flow characteristics is found to be non-uniform. For smaller values of [Formula: see text] [Formula: see text] the axial pressure gradient decreases by nearly [Formula: see text] whereas the velocity profile remains almost unchanged. This indicates that weak viscoelasticity primarily alters the stress distribution and reduces the pressure required for peristaltic pumping without significantly modifying the kinematics of the flow. However, for moderate values of [Formula: see text] [Formula: see text], the velocity increases by about [Formula: see text] with [Formula: see text], showing that elastic memory becomes sufficiently strong to enhance axial transport. Hence, the Johnson-Segalman fluid exhibits a transition from a pressure-adjustment regime at low [Formula: see text] to a flow-enhancement regime at higher [Formula: see text]. So in drug-delivery language, small increases in elasticity improve efficiency, while larger increases improve throughput. For targeted colonic delivery, keep [Formula: see text] to suppress persistent bolus trapping. Why? Since the size of the trapped bolus decreases as [Formula: see text] increases, as shown in Fig. 11, this means that, if the goal is uniform axial delivery with minimal recirculation, you generally do not want to operate in a regime where trapped closed streamlines are large and persistent. In fact, small [Formula: see text] means more Newtonian-like and, hence, often a larger bolus, but moderate Wi produces a smaller trapped bolus; it may also create elastic memory and concentration lag. So, for drug delivery, the best practical interpretation is: Use [Formula: see text] as a conservative “low trapping / low memory” starting range because it is usually below the regime where elasticity begins to dominate residence-time behavior. On the other hand, both dynamic and effective viscosities have opposing effects on the fluid’s velocity and pressure gradient profiles. Also, raising the chemical reaction parameter reduces the pressure rise within the channel. The obtained findings have direct applications in biomedical engineering and drug delivery system designs.