Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Dec 15;14(12):2814.
doi: 10.3390/pharmaceutics14122814.

Expandable Drug Delivery Systems Based on Shape Memory Polymers: Impact of Film Coating on Mechanical Properties and Release and Recovery Performance

Marco Uboldi  1 , Chiara Pasini  2 , Stefano Pandini  2 , Francesco Baldi  2 , Francesco Briatico-Vangosa  3 , Nicoletta Inverardi  2 , Alessandra Maroni  1 , Saliha Moutaharrik  1 , Alice Melocchi  1 , Andrea Gazzaniga  1 , Lucia Zema  1
Affiliations

Expandable Drug Delivery Systems Based on Shape Memory Polymers: Impact of Film Coating on Mechanical Properties and Release and Recovery Performance

Marco Uboldi et al. Pharmaceutics. .

Abstract

Retentive drug delivery systems (DDSs) are intended for prolonged residence and release inside hollow muscular organs, to achieve either local or systemic therapeutic goals. Recently, formulations based on shape memory polymers (SMPs) have gained attention in view of their special ability to recover a shape with greater spatial encumbrance at the target organ (e.g., urinary bladder or stomach), triggered by contact with biological fluids at body temperature. In this work, poly(vinyl alcohol) (PVA), a pharmaceutical-grade SMP previously shown to be an interesting 4D printing candidate, was employed to fabricate expandable organ-retentive prototypes by hot melt extrusion. With the aim of improving the mechanical resistance of the expandable DDS and slowing down relevant drug release, the application of insoluble permeable coatings based on either Eudragit® RS/RL or Eudragit® NE was evaluated using simple I-shaped specimens. The impact of the composition and thickness of the coating on the shape memory, swelling, and release behavior as well as on the mechanical properties of these specimens was thoroughly investigated and the effectiveness of the proposed strategy was demonstrated by the results obtained.

Keywords: expandable drug delivery system; film-coating; fused deposition modeling; hot melt extrusion; poly(vinyl alcohol) (PVA); retentive drug delivery system; shape memory polymer.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Design concept of expandable DDSs based on SMPs intended for retention in hollow muscular organs (dimensions are in mm).
Figure 2
Figure 2
Outline of the A-E positions where I-shaped samples were cut and photographed, showing a cross-section with details relevant to the d1-d6 coating thickness measurements.
Figure 3
Figure 3
Outline of the different positions where the swollen I-shaped samples were cut and photograph of a cross-section with details relevant to the different areas measured.
Figure 4
Figure 4
Coating thickness versus amount of coating applied to I-shaped samples.
Figure 5
Figure 5
Thermograms of uncoated and coated (i.e., R8 and N8) samples, and of free Eudragit® RS/RL and Eudragit® NE films; the insert is a magnification of the glass transition regions.
Figure 6
Figure 6
Average release profiles from uncoated and coated samples.
Figure 7
Figure 7
Profiles of (a) mass variation and (b) diameter increase plotted versus immersion time relevant to uncoated and coated samples.
Figure 8
Figure 8
(a) Photographs of cross-sections of uncoated and coated N8 prototypes at different positions along their length after increasing immersion times and (b) profiles of the corresponding swollen area.
Figure 9
Figure 9
Profiles of swollen area in the central cross-section of uncoated and coated samples as a function of the immersion time.
Figure 10
Figure 10
(a) Stress versus strain curves relevant to uncoated, R8, and N8 specimens tested under tensile conditions after different immersion times, and profiles of (b) E as well as of (c) σ10% as a function of immersion time.
Figure 11
Figure 11
(a) Normalized load versus normalized displacement curves relevant to uncoated, R8, and N8 specimens tested under compressive conditions after different immersion times and (b) profiles of S* as a function of immersion time.
Figure 12
Figure 12
RI versus time curves relevant to I-shaped samples coated with different formulations.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

References

    1. Bardonnet P., Faivre V., Pugh W., Piffaretti J., Falson F. Gastroretentive dosage forms: Overview and special case of Helicobacter pylori. J. Control. Release. 2006;111:1–18. doi: 10.1016/j.jconrel.2005.10.031. - DOI - PubMed
    1. Gupta R., Tripathi P., Bhardwaj P., Maho A. Recent advances in gastro retentive drug delivery systems and its application on treatment of H. Pylori infections. J. Anal. Pharm. Res. 2018;7:404–410. doi: 10.15406/japlr.2018.07.00258. - DOI
    1. Lopes C.M., Bettencourt C., Rossi A., Buttini F., Barata P. Overview on gastroretentive drug delivery systems for improving drug bioavailability. Int. J. Pharm. 2016;510:144–158. doi: 10.1016/j.ijpharm.2016.05.016. - DOI - PubMed
    1. Melocchi A., Uboldi M., Cerea M., Foppoli A., Maroni A., Moutaharrik S., Palugan L., Zema L., Gazzaniga A. Shape memory materials and 4D printing in pharmaceutics. Adv. Drug Deliv. Rev. 2021;173:216–237. doi: 10.1016/j.addr.2021.03.013. - DOI - PubMed
    1. Vrettos N.-N., Roberts C.J., Zhu Z. Gastroretentive Technologies in Tandem with Controlled-Release Strategies: A Potent Answer to Oral Drug Bioavailability and Patient Compliance Implications. Pharmaceutics. 2021;13:1591. doi: 10.3390/pharmaceutics13101591. - DOI - PMC - PubMed