Modeling of non‐Fickian diffusion and dissolution from a thin polymeric coating: An application to drug‐eluting stents

Abstract

Summary In this paper, we present a general model for non‐Fickian diffusion and drug dissolution from a controlled drug delivery device coated with a thin polymeric layer. First, we study the stability and deduce an analytic solution to the problem. Then, we consider this solution and provide suitable boundary conditions to replace the problem of mass transport in the coating of a coronary drug‐eluting stent. With this approach, we reduced the computational cost of performing numerical simulations in complex 3‐dimensional geometries. The model for mass transport by a coronary drug‐eluting stent is coupled with a non‐Newtonian blood model flow. In order to show the effectiveness of the method, numerical experiments and a model validation with experimental data are also included. In particular, we investigate the influence of the non‐Newtonian flow regime on the drug deposition in the arterial wall.

Electrostatic Induced Peptide Hydrogels for pH‐Controllable Doxorubicin Release and Antitumor Activity

“…Combining the data in Table 3, it can be seen that n=0.492>0.45 for pH 7.4, which belongs to Non‐Fickian diffusion (Table 4). The interaction force between the hydrogel backbone and the drug is significantly enhanced in this release mechanism [49] . This is also the same as its principle of action that the electrostatic interaction between DOX and FFWDD at pH 7.4 is not disrupted and a strong interaction relationship is always maintained.…”

“…The interaction force between the hydrogel backbone and the drug is significantly enhanced in this release mechanism. [49] This is also the same as its principle of action that the electrostatic interaction between DOX and FFWDD at pH 7.4 is not disrupted and a strong interaction relationship is always maintained. While n = 0.36 < 0.45 for pH 5.5, which belongs to Quasi-Fickian diffusion (Table 4).…”

Adhesion properties of poly(methylmethacrylate‐co‐n‐butylmethacrylate) copolymers in stent coatings

“…With the aim to limit late complications of bare metal stents, the class of drug‐eluting stents (DES) has emerged in the last few decades, becoming a well consolidate practice for stenosis treatment and restenosis prevention . DES strength lies in the capability to topically release one or more drugs with a controlled rate . The majority of DES provides the controlled drug delivery kinetics by means of polymeric drug‐loaded coatings .…”

“…1 DES strength lies in the capability to topically release one or more drugs with a controlled rate. 2 The majority of DES provides the controlled drug delivery kinetics by means of polymeric drug-loaded coatings. 3 However, while the use of a polymer provides some benefits in DES performances, they should be carefully selected to meet specific chemical, biological, and regulatory requirements.…”