Polymer/Iron-Based Layered Double Hydroxides as Multifunctional Wound Dressings.

Mariana Pires Figueiredo,César Viseras,Vera Regina Leopoldo Constantino,Silvia Rossi,Giuseppina Sandri,Fátima García-Villén,Ana Borrego-Sánchez,Dalila Miele

doi:10.3390/pharmaceutics12111130

Abstract

This work presents the development of multifunctional therapeutic membranes based on a high-performance block copolymer scaffold formed by polyether (PE) and polyamide (PA) units (known as PEBA) and layered double hydroxide (LDH) biomaterials, with the aim to study their uses as wound dressings. Two LDH layer compositions were employed containing Mg2+ or Zn2+, Fe3+ and Al3+ cations, intercalated with chloride anions, abbreviated as Mg-Cl or Zn-Cl, or intercalated with naproxenate (NAP) anions, abbreviated as Mg-NAP or Zn-NAP. Membranes were structurally and physically characterized, and the in vitro drug release kinetics and cytotoxicity assessed. PEBA-loading NaNAP salt particles were also prepared for comparison. Intercalated NAP anions improved LDH–polymer interaction, resulting in membranes with greater mechanical performance compared to the polymer only or to the membranes containing the Cl-LDHs. Drug release (in saline solution) was sustained for at least 8 h for all samples and release kinetics could be modulated: a slower, an intermediate and a faster NAP release were observed from membranes containing Zn-NAP, NaNAP and Mg-NAP particles, respectively. In general, cell viability was higher in the presence of Mg-LDH and the membranes presented improved performance in comparison with the powdered samples. PEBA containing Mg-NAP sample stood out among all membranes in all the evaluated aspects, thus being considered a great candidate for application as multifunctional therapeutic dressings.

Highlights

Multifunctional therapeutic dressings that are able to act in the tissue regeneration process, besides play-acting as physical protective barriers against infection, occupy a high level of interest in pharmaceutical technology
This work presents the development of multifunctional therapeutic membranes based on a high-performance block copolymer scaffold formed by polyether (PE) and polyamide (PA) units and layered double hydroxide (LDH) biomaterials, with the aim to study their uses as wound dressings
An appreciable amount of carbon is verified for both Mg4FeAl-NAP and Zn4FeAl-NAP LDHs, whose NAP percentage corresponds to 36.35% and 26.64% of the material’s mass, respectively

Summary

Introduction

Multifunctional therapeutic dressings that are able to act in the tissue regeneration process, besides play-acting as physical protective barriers against infection, occupy a high level of interest in pharmaceutical technology. Structural neutrality of LDH is guaranteed by the presence of hydrated anions (An−) between the layers [1,2]. Anti-inflammatories [15,16] and bactericidal [17,18,19] species are examples of organic guests, already loaded into LDH, that can promote a faster and painless wound healing process. Such process is characterized by a sequence of four complex, overlapped and regulated phases: hemostasis, inflammation, proliferation and remodeling [20].

Results

Discussion

Conclusion