Patchwork Coating of Fragmented Ultra-Thin Films and Their Biomedical Applications in Burn Therapy and Antithrombotic Coating

Abstract

We have proposed free-standing centimeter-sized ultra-thin films (nanosheets) for biomedical applications. Such nanosheets exhibit unique properties such as transparency, flexibility, and good adhesiveness. However, they are only easily adhered to broad and flat surfaces due to their dimensions. To this end, we recently proposed an innovative nanomaterial: the nanosheets fragmented into submillimeter-size pieces. Intriguingly, such fragmented nanosheets could be adhered to uneven and irregular surfaces in addition to flat surfaces in a spread-out “patchwork” manner. We herein review the fabrication procedure and characterization of fragmented nanosheets composed of biodegradable polyesters and thermostable bio-friendly polymers, and their biomedical applications in burn therapy and antithrombotic coating using a “patchwork coating”.

Adhesive and robust multilayered poly(lactic acid) nanosheets for hemostatic dressing in liver injury model

“…PVA acts as an excellent water‐soluble sacrificial layer to release the PLLA nanosheets from the SiO 2 substrate as reported priviously . Moreover, we have proposed a one‐pot fabrication process that uses multilayering of PVA and PLLA on the substrate to collect a large number of free‐standing PLLA nanosheets . This technique seems to be helpful to fabricate multilayered nanosheets, however, the nanosheets fabricated by using only PVA as a sacrificial layer were discretely separated when the PVA was dissolved in water .…”

“…[11][12][13] Moreover, we have proposed a one-pot fabrication process that uses multilayering of PVA and PLLA on the substrate to collect a large number of free-standing PLLA nanosheets. 30,31 This technique seems to be helpful to fabricate multilayered nanosheets, however, the nanosheets fabricated by using only PVA as a sacrificial layer were discretely separated when the PVA was dissolved in water. 30,31 To this end, we focused on Na-Alg, which can be converted instantly into a gel by adding divalent cations and can be redissolved by adding chelating reagents such as EDTA.…”

“…30,31 This technique seems to be helpful to fabricate multilayered nanosheets, however, the nanosheets fabricated by using only PVA as a sacrificial layer were discretely separated when the PVA was dissolved in water. 30,31 To this end, we focused on Na-Alg, which can be converted instantly into a gel by adding divalent cations and can be redissolved by adding chelating reagents such as EDTA. 32 In fact, the multilayered nanosheets could be temporarily handled as a thick composite film when Na-Alg was converted into gels between the nanosheets.…”

Biodegradable Polymer Nanosheets Incorporated with Zn-Containing Nanoparticles for Biomedical Applications

“…The treatment of burn wound is known to be a long-lasting and complex process that requires new therapeutic options to improve and accelerate the healing progress [1][2][3][4][5][6][7][8]. An ideal wound dressing should accelerate one or several stages of the healing processes including the inflammatory, migratory, proliferative, and remodeling phases.…”

“…An ideal wound dressing should accelerate one or several stages of the healing processes including the inflammatory, migratory, proliferative, and remodeling phases. A variety of wound dressings are available and still widely used to treat such wounds [1][2][3][4][7][8][9][10]. And even though the properties of ultimate wound dressings are well identified, major difficulties arise when it comes to combining them within the same material [1][2][3][4]7,9].…”