Fabrication of free‐standing albumin‐nanosheets having heterosurfaces

Abstract

Sheet-shaped carriers, having both obverse and reverse surfaces and thus a large contact area for targeting a site, have several advantages over spherical-shaped carriers, which have an extremely small contact area for targeting sites. Here, we proposed a novel method to prepare a free-standing ultrathin and biocompatible nanosheet having heterosurfaces, by a combination of four processes: (1) specific adsorption of recombinant human serum albumin (rHSA) molecules onto a patterned octadecyltrimethoxysilane self-assembled monolayer region (ODS-SAM), (2) preparation of nanosheets of rHSA molecules bearing thiol groups (SH-rHSA) via two-dimensionally disulfide crosslinking, (3) surface modification of the resulting nanosheet, and (4) preparation of the free-standing nanosheet by detachment from the ODS-SAM. The SH-rHSA molecules at pH 5.0 and a concentration of 1 microg/mL were specifically adsorbed on the patterned ODS-SAM regions by hydrophobic interaction, and were two-dimensionally crosslinked in the presence of copper ion as an oxidant. The rHSA-nanosheets were then simply detached from the ODS-SAM by treatment with surfactant. We succeeded in the preparation of rectangular (10 microm x 30 microm) and ultrathin (4.5 +/- 1.0 nm) rHSA-nanosheets on a patterned ODS-SAM, and could also obtain free-standing rHSA-nanosheets having heterosurfaces by surface modification with fluorescent latex beads. Thus, the rHSA-nanosheets having heterosurfaces could be regarded as a new biomaterial for drug carriers, hemostatic reagents, wound dressing for burn injury, and so forth.

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

“…The TMs covered with the nanosheet were set into a 24‐well plate filled with 1 mL of PBS. As model analytes, 10 mg/mL solution of rhodamine B (Rho B; Mw: 479 Da, E x : 570 nm, E m : 590 nm; Sigma‐Aldrich Co.) or BSA labeled with fluorescein isothiocyanate (FITC‐BSA, E x : 494 nm, E m : 518 nm, referred to Supporting material) were utilized for the permeation test. An aliquot of each analyte (200 μL) was pipetted into the inner compartment of the nanosheet‐coated TM, which was then incubated at 37°C in a shaking bath (SB‐13; ASONE Co.).…”

Facile fabrication of elongated polymer micro/nano discs and their surface adhesiveness

“…[6][7][8][9] However, many studies have been shifted to fabricate nonspherical polymer particles in these past several years to utilize their unique and fascinating properties. [10][11][12][13][14][15][16][17][18][19][20] One of the most essential properties especially in drug delivery application is surface adhesiveness. To execute its diagnostic or therapeutic mission, the particle has to firmly adhere to the surface of the target sites (e.g., blood vessel wall or tumor).…”

“…These particles have been used in a wide range of applications 1–5 and can be fabricated via various methods 6–9 . However, many studies have been shifted to fabricate nonspherical polymer particles in these past several years to utilize their unique and fascinating properties 10–20 . One of the most essential properties especially in drug delivery application is surface adhesiveness.…”

Microfluidic Electrospray of Multifunctional Discal Microparticles for Wound Healing

“…In this paper, we proposed a novel multifunctional wound microcarrier dressing based on microfluidics-derived discal microparticles (DMPs) for wound healing, as shown in Figure . Microfluidic technology is well-known as a maneuverable strategy to fabricate monodispersed microparticles for applying in diverse areas. − Especially, the combination of microfluidic electrospray with biomaterials has opened up novel avenues for fabricating microcarriers, most of which are spherical as wound dressing. , Although with many values, these general spherical microcarriers are easy to shift and fall off due to the small contact area, which greatly affects their stability on the wound surface . In contrast, the microparticles in discal morphology exhibit prominent advantages of higher surface/volume ratio, better deformability, and side stacking capability. − Thus, it is conceived that an effective approach for wound healing can be achieved by harnessing discal microparticles as a wound dressing.…”

“…29,30 Although with many values, these general spherical microcarriers are easy to shift and fall off due to the small contact area, which greatly affects their stability on the wound surface. 31 In contrast, the microparticles in discal morphology exhibit prominent advantages of higher surface/volume ratio, better deformability, and side stacking capability. 32−35 Thus, it is conceived that an effective approach for wound healing can be achieved by harnessing discal microparticles as a wound dressing.…”