## 3 Discussion  
Simulations were performed to confirm the dynamics of the particles through the tumor microenvironment and the behavior of vectorized coupling. The intraluminal pressure of the colon and prescribed pressure inside the tumor were considered, with the purpose of guaranteeing natural pressure conditions that affected the mobility of the particles (nanocarriers). The convergence of the computational solutions was achieved; however, the numerical stabilization was complex due to the non-linearity condition of the behavior of the phenomenon formed by the Navier-Stokes model and the Brownian behavior model of the nanocarriers. From the literature, it is known that once the drug is ingested, the vectorized nanocarriers travel through the gastrointestinal system reaching the region of the colon where the lesion is located. The maximum mean inhibitory concentration of \(\mathrm{C_{p}}=13.5\frac{\mathrm{\mu g}}{\mathrm{mL}}\) used [32; 33] allowed for the adequate parameterization of the initial absorption conditions of the drug through the mucosal layer, which contributed to obtaining more precise results in terms of the mass flow of the nanoparticles. In all histological evaluations it was evidenced that the velocity of absorption of nutrients and liquids through the walls from the lumen of the colon towards the interior of the tumor was \(2.48\times 10^{-8}\frac{\mathrm{m}}{\mathrm{s}}\), which is consistent with the values estimated by [34] (on the order of \(10^{-8}\frac{\mathrm{m}}{\mathrm{s}}\)). The results of the samples confirmed that the velocities obtained from the interstitial fluid were above the range of biological operability. In the tumor microenvironment there are different types of cells, such as goblet cells and enterocytes, which are responsible for mucin production and water absorption [35], as  
Figure 10: Velocity achieved by the liposomes to attach to the surface of malignant cell regions in the histological sample by means of 3D simulation. **(a)** Liposome coupled 4200 s after administration of the first dose of treatment. **(b)** Liposome coupled 12,680 s after administration of the first dose of treatment. The main difference between these two particles (besides the time in which they couple) is that particle **(b)** continues to increase its speed as it travels to deeper regions, while particle **(a)** maintained a relatively stable velocity. well as B and T lymphocytes, which are part of the immune system and which are usually found in greater numbers in the interstitial space of malignant regions. In this research, groups of goblet cells and enterocytes are taken into account, which form regions called glands; while the treatment given to lymphocytes consists of incorporating them as part of the interstitial fluid, assigning porosity properties to the medium. In the regions of cancerous tissue, there are many glands distributed with little interstitial space between them, due to the morphological irregularity of the malignant cells that compose them. In selected samples, larger interstitial space regions can also be seen between the healthy glands and the cluster of cancerous glands. This morphological arrangement of the tumor microenvironment can influence the behavior of nanocarriers, giving rise to four different situations:  
1. The interstitial space between at least one pair of glands is narrow, which increases the velocity of the interstitial fluid, driving the liposomes through the streamlines at speeds sufficient to escape the electrostatic surface attraction forces of the cancerous glands;
2. The interstitial space between at least one pair of glands is narrow enough so that the liposomes transiting in between, despite increasing their speed, have a trajectory close enough to the boundary layer of the gland surface, which slows down their speed and allows attractive forces to act on the liposome, increasing the probability of engagement with the cancerous region;
3.