Stearic Acid-Modified Starch/Chitosan Composite Sponge with Asymmetric and Gradient Wettability for Wound Dressing

Abstract

In this work, we developed a facile approach for the fabrication of stearic acid-modified starch/chitosan composite sponge with asymmetric wettability and gradient wettability via mediating the amount of starch. The starch/chitosan composite sponge exhibited heterogeneous wetting properties on its two surfaces after stearic acid modification. The superhydrophobic top surface with a water contact angle of 150°could prevent water, blood, and bacterial permeation without losing the breathability of the sponge, whereas the superhydrophilic bottom surface possessed optimal water and blood absorption and clotting abilities. The asymmetric wettability of starch/chitosan composite sponge was attributed to the synergistic contribution of gradient distribution of starch, rough three-dimensional skeleton structure induced capillary effect and the nonuniform surface distribution of hydrophilic/hydrophobic groups. Furthermore, the sponge also possessed good biodegradability and noncytotoxicity to the human normal hepatocyte. The results indicated that the stearic acid-modified starch/chitosan composite sponge with ideal liquid absorption, vapor transmission rate, self-cleaning and stain-repellent ability could be used as a promising candidate for wound dressing.

Efficient, biosafe and tissue adhesive hemostatic cotton gauze with controlled balance of hydrophilicity and hydrophobicity

“…Hemostatic gauze with proper water vapor transmission and liquid absorption can prevent dehydration and excessive accumulation of exudates. Therefore, they can control water/blood loss and create an ideal moist environment for wound healing 22 . The water vapor permeation rate of cotton gauze, ABO-g-gauze, HTMS-g-gauze, and USO-g-gauze is ca.…”

Carbon dots crosslinked chitosan/cellulose sponge capture of methyl blue by an adsorption process

“…The resolved peaks in the C1s spectrum (Figure 3b) were located at 285.40, 284.75, 286.35, and 288.15 eV, which were assigned to the C–C/C–H, C–N, C–O, and O–C–O/C=O groups, respectively. [ 33,34 ] In addition, the peaks at 399.15 and 399.70 eV in the N1s spectra (Figure 3c) corresponded to the C–N and N–H groups, respectively. [ 35 ] As illustrated in the O1s spectra (Figure 3d), the peaks at 531.20, 531.80, and 532.70 eV were characteristic peaks of O–C–O/C=O, O–H, and C–O, respectively.…”

A super-efficient and biosafe hemostatic cotton gauze with controlled balance of hydrophilicity/hydrophobicity and tissue adhesiveness

“…Therefore, they can control water/blood loss and create an ideal moist environment for wound healing. 22 The water vapor permeation rate of cotton gauze, ABO-g-gauze, HTMS-g-gauze, and USO-g-gauze was 1028, 1023, 1021, and 1015 g•m -2 •day -1 at 37 o C, respectively (Fig. 3c), suggesting that water vapor permeability of the three surface modified gauzes is as good as that of standard cotton gauze, due to their breathable knitted fabric structure.…”

“…Therefore, they can 3 control water/blood loss and create an ideal moist environment for wound healing. 22…”