Biodegradable Sodium Alginate Research Articles

Highly Performing Polysaccharide Hydrogels can Replace Acrylic Acid‐Based Superabsorbent Polymers in Sanitary Napkins

AbstractSuper absorbent polymers (SAPs) used in sanitary napkin are not required for water absorption capacity as high as in baby diapers and adult incontinence pads. Sanitary napkins must absorb menses, which is delivered at a significantly lower rate and overall daily amount than urines. Thus, the acrylic acid (AA) component can not be strictly necessary. By proper formulation design and processing, polysaccharide SAPs can be equally or even better performing than AA‐containing SAPs in sanitary napkins. Fully biodegradable sodium alginate (SA)‐based SAPs are prepared through ionic cross‐linking by CaCl2 and introduced in female pads. The optimal solution concentrations (SA 8% w/v, CaCl2 0.25% w/v in water) and reaction time are identified, and addition of cellulose nanocrystals (CNC) at different weight contents (0–3 w%) is tested. Morphology, physico‐chemical properties, rheology, free swelling capacity (FSC), centrifuge retention capacity, and weight loss in soil are assessed. Increasing CNC content decreases FSC. Rheology results demonstrate higher storage and loss moduli for SA‐based SAPs versus commercial SAPs. The superior SA‐SAP developed is used in varying amounts for manufacturing sanitary napkin prototypes, revealing that excellent menstrual fluid absorption, surpassing commercial pads. Replacing AA‐based with polysaccharide‐based SAPs would reduce the environmental impact of hygienic product waste.

Polycomplexes to modulate bactericidal activity of cetylpyridinium bromide

Cetylpyridinium bromide, a quaternary ammonium surfactant, was electrostatically complexed with an excess of anionic polymers such as biodegradable sodium alginate or non-biodegradable sodium polyacrylate. The binding of surfactant with alginate delivered polymer–surfactant complexes capable of killing both more surfactant-sensitive Escherichia coli and less surfactant-sensitive Pseudomonas aeruginosa bacteria, while the binding with acrylate gave complexes active only against Escherichia coli. The results obtained show a way for adjustment of the antimicrobial formulation to a specific pathogen to be destroyed.

Engineering Biodegradable Sodium Alginate Films with Dragon Fruit Peel Powder and MgO Nanoparticles

This study investigated the effect of the addition of dragon fruit peel powder (DFP) and MgO nanoparticles on sodium alginate (SA) films. The control film (S1 film), DFP-enriched (S2 film), MgO nanoparticles-enhanced (S3 film), and a film combining both MgO nanoparticles and DFP (S4 film) were evaluated. The tensile strength increased by 252.43, 290.27, and 645.13% for the S2, S3 and S4 films, respectively. These enhancements were accompanied by a marked improvement in the UV-blocking property, thermal stability, antioxidant activity,2,2′-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity, opacity and thickness. The water vapor permeability and transparency were decreased to 3.45 × 10−10 g−1 Pa−1 S−1 and 1.82% for the S4 film. An environmental scanning electron microscope (ESEM) study revealed a notable increase in surface roughness with the incorporation of DFP. X-ray diffraction (XRD) analysis indicated that the MgO nanoparticles possessed a crystallographic structure that was compatible with the SA film matrix, with the S4 films exhibiting the highest crystallinity index (28.92%). The overall migration study showed that all SA films complied with the overall migration limit of 60 mg/kg of simulant for fatty food simulants. The biodegradability test revealed complete degradation of the S1, S3, and S4 films before 20 days while the S2 film exhibited a substantial mass loss of 84.99% within the same 20-day timeframe.

Comparative catalytic reduction and degradation with biodegradable sodium alginate based nanocomposite: Zinc oxide/N-doped carbon nitride/sodium alginate

Sodium alginate (SA) is a biodegradable macromolecule which is used to synthesize nanocomposites and their further use as catalysis. Zinc oxide (ZnO) and nitrogen doped carbon nitride (ND-C3N4) nanoparticles are prepared using solvothermal and hydrothermal methods, respectively. ZnO/ND-C3N4/SA nanocomposites are successfully synthesized by employing in-situ polymerization. The presence of essential functional groups is confirmed by Fourier transform infrared (FTIR) spectroscopic analysis. Controlled spherical morphology for ZnO nanoparticles, with an average diameter of ∼52 nm, is shown by Scanning electron microscopic (SEM) analysis, while rice-like grain structure with an average grain size ∼62 nm is exhibited by ND-C3N4 nanoparticles. The presence of required elements is confirmed by Energy dispersive X-ray spectroscopic (EDX) analysis. The crystalline nature of nanocomposites is verified by X-ray diffraction spectroscopic (XRD) analysis. The investigation of the catalytic efficiency for degradation and reduction of various organic dyes is carried out on nanoparticles and nanocomposites. Thorough examination and comparison of parameters, such as apparent rate constant (kapp), reduction time, percentage reduction, reduced concentration and half-life, are conducted for all substrates. The nanocomposites show greater efficiency than nanoparticles in both reactions: catalytic reduction and catalytic degradation.

An innovative bilayer solid carbon source for tertiary denitrification: Synthesis, performance, and microbial diversity analysis

The low C/N ratio poses a constraint on the tertiary nitrogen removal process in domestic sewage. Composite solid carbon sources have recently gained attention in recent years for improving nitrogen removal efficacy. However, little research has focused on the lengthy start-up of denitrification systems caused by composite solid carbon sources. In this study, we employed a biodegradable sodium alginate (SA) and corn cob (CC) mixture, implanted a polycaprolactone (PCL) and corn starch (CS) mixture, and created a new composite solid carbon source polycaprolactone-corn starch‑sodium alginate-corn cob microspheres (PCSC). The early rapid carbon release and late stable carbon release properties of PCSC allow it to rapidly enrich denitrifying bacteria and form biofilms on its surface. It only takes 5 days to start denitrification biological filters utilizing PCSC as a carbon source, with an average nitrogen removal rate of 85 %, which is 60 % and 10 % higher than SA-CC and PCL-CS, respectively. The 16S rRNA gene high-throughput sequencing revealed that the primary denitrifying bacteria on the surface of PCSC were Chitinophagaceae, Comamonadaceae, and Blastocatellaceae. Overall, PCSC can make the denitrification system start up fast, steadily, and efficiently, and it has tremendous application prospects in tertiary nitrogen removal of wastewater.

Biodegradable, transparent, and antibacterial alginate-based triboelectric nanogenerator for energy harvesting and tactile sensing

The utilization of natural biomaterials in the construction of triboelectric nanogenerators (TENG) has significant implications for the advancement of sustainable self-powered devices. Sodium alginate (SA), an eco-friendly and biodegradable triboelectric material with excellent transparency, is considered an ideal material for wearable TENGs. In this work, we report a biodegradable, transparent, and antibacterial SA-based TENG for mechanical energy harvesting and self-powered tactile sensing. The addition of glycerol, an environment-friendly additive, can enhance flexibility and adhesiveness of the SA, which resulted in well-transferred AgNWs/SA electrodes with high transparency and conductivity. The major parameters that affect the output performance of the fabricated TENG are investigated, including the frequency, thickness and area of the triboelectric layers. The output voltage, transferred charge, and peak power of the TENG could reach up to 53 V, 18 nC, and 4 μW, respectively, which is sufficient to power small electronic devices. In addition, the fabricated TENG device also shows excellent antibacterial and biodegradable capabilities. Finally, the TENG is demonstrated to be an effective self-powered tactile sensor for pressure mapping, human movement monitoring, and wearable human–machine interfacing. This work provides a new strategy to design flexible transparent TENGs with biodegradable SA and paves the way for developing next-generation self-powered transient electronics.

Biodegradable sodium alginate films incorporated with lycopene and β-carotene for food packaging purposes.

Incorporating carotenoids into sodium alginate films can give them functional properties for food packaging applications. The lycopene and β-carotene were included in the biopolymer matrix at 0.1%, 0.3%, and 0.5% (g carotenoid/g polymer). There was no significant difference (p > 0.05) in film thickness (45 ± 1 μm) of sodium alginate films with carotenoids. Nevertheless, the low quantity of carotenoids was enough to promote significant variations in the tensile properties of films. The films with lycopene or β-carotene showed lower tensile strength and elongation at break than control films. The carotenoid incorporation promoted a reduction (p < 0.05) in water vapor permeability, mainly by adding 0.5%. In the same way, it improved the light transmission and thermal stability of films and did not affect the water solubility of films. The scanning electron microscopy of films showed a homogeneous surface, but the films with lycopene or β-carotene showed a more compact structure than the control film. The sodium alginate films incorporated with 0.3% lycopene or β-carotene showed a remarkable protective effect on sunflower oil against oxidation compared with traditional commercial plastic packaging under accelerated storage conditions (heat and light). Therefore, they can be considered a potential material for food packaging purposes.

Eco-Friendly OSN Membranes Based on Alginate Salts with Variable Nanofiltration Properties

In this work, membranes for organic solvents nanofiltration (OSN) based on a natural polymer, sodium alginate, were fabricated. They are chemically stable in organic solvents, including aprotic polar solvents. The unique advantage of these membranes is the absence of toxic reagents and solvents during their production. This ensures the safety and environmental friendliness of the production process. It has been shown that an operation as simple as changing the cation in alginate (Cu2+, Fe3+, Cr3+, Al3+, Zn2+, Ca2+) makes it possible to control the transport and separating properties of membranes, depending on the organic solvent being separated. Therefore, to isolate RemazolBrilliant Blue with MM = 626 g·mol-1 from ethanol, membranes based on iron alginate with a rejection R = 97% and a permeability of 1.5 kg·m-2·h-1·bar-1 are the most efficient. For isolation of the same solute from DMF and MP, membranes based on calcium alginate with an R of about 90% and a permeability of 0.1-0.2 kg·m-2·h-1·bar-1 are the most efficient. The resulting membranes based on natural biodegradable sodium alginate are competitive compared to membranes based on synthetic polymers.

Porous Biodegradable Sodium Alginate Composite Fortified with Hibiscus Sabdariffa L. Calyx Extract for the Multifarious Biological Applications and Extension of Climacteric Fruit Shelf-Life

Porous Biodegradable Sodium Alginate Composite Fortified with Hibiscus Sabdariffa L. Calyx Extract for the Multifarious Biological Applications and Extension of Climacteric Fruit Shelf-Life

Study of the JAK inhibitors antifibrotic activity for the prevention and treatment of chronic thromboembolic pulmonary hypertension

Introduction. Chronic thromboembolic pulmonary hypertension (CTEPH) is the most common complication of pulmonary thromboembolism (PE). Fibrous remodeling of the pulmonary circulation vessels against the background of CTEPH leads to an irreversible increase of the vessel wall stiffness and the ineffectiveness of CTEPH treatment. The involvement of Janus kinase (JAK) in the regulation of vascular wall and lung tissue inflammation and fibrosis allows for the possible effectiveness of JAK 1,2 inhibitors (iJAK) in the course of CTEPH. Purpose – to study the antifibrotic effect of iJAK for the prevention and treatment of CTEPH. Materials and methods. The study was conducted on male Wistar rats. Modeling of CTEPH was performed by sequential embolization of the vascular bed with partially biodegradable sodium alginate microspheres. 2 weeks after the last administration of the microspheres, low, medium and high doses of iJAK were initiated. To assess the effectiveness of the substance, the following tests were used: treadmill test, echocardiography, cardiac catheterization with right ventricular (RV) manometry, histological examination of the lungs. Results. Animals undergone vascular embolization demonstrated decreased exercise tolerance at all observation points compared to healthy animals. The placebo group, in contrast with the group getting treatment and iJAK, was found to have an increased mean RV pressure compared to healthy animals. There was an increase in mean RV pressure in the placebo group (15.5±7.7 mmHg) and in the low dose and iJAK group (13.4±6.4 mmHg) compared with healthy animals (9.4±2.2 mmHg). Vascular hypertrophy of the pulmonary artery branches was lower in group getting average dosages and iJAK compared with the placebo group (54.9±19.0 and 68.9±23.1 %, respectively). Thus, the suppression by iJAK of aseptic inflammation and following fibrosis leads to the decreasing of severity of pulmonary circulation remodeling in the experimental model of CTEPH. This approach can be used in the comprehensive bypass and prevention of CTEPH.

Active-intelligent and biodegradable sodium alginate films loaded with Clitoria ternatea anthocyanin-rich extract to preserve and monitor food freshness

The aim of this study was to develop and characterize sodium alginate films loaded with 10–40 % Clitoria ternatea extract (CTE) and apply to monitoring the quality of milk, pork and shrimp. Films loaded with CTE showed high light barrier capacity and improved tensile strength by 3.8 times over control films. The incorporation of CTE in alginate films improved the thermal stability of the materials due to intermolecular interactions and crosslinking of polymeric networks. The addition of 40 % of CTE generated films with antibacterial action against E. coli. The alginate films showed biodegradable characteristics in soil and beach sand in 15 days. The food simulant test revealed that the loaded films show good compatibility with aqueous and acidic foods due to the release of higher levels of polyphenols and anthocyanins. The films showed great colorimetric potential due to their ability to change color at different pH (pink-green), ammonia gas (blue-green) and sterilization process (blue-yellow). When the film loaded with 40 % CTE (F40) was applied to monitor the freshness of milk and meat products (shrimp and pork), its blue color changed to purple and green, respectively. Therefore, the F40 has great potential to be used as a biodegradable indicator of freshness.

A novel sodium alginate active films functionalized with purple onion peel extract (Allium cepa)

The purple onion peel extracts (POPE) have a high content of phenolic compounds and can be used as a promising strategy in the development of active packaging. Biodegradable sodium alginate films have good characteristics of gel formation, flexibility, transparency, brightness, and low oil permeability. The incorporation of bioactive compounds from plant residues can be a low-cost technique to functionalize alginate-based materials. The aim of this work was to evaluate the effects of POPE incorporation on the physical, mechanical, barriers, antioxidants, and antimicrobial properties of alginate-based films. Filmogenic solutions were prepared with a concentration of 0, 10, 20, and 30% of POPE and glycerol was used as plasticizer. The addition of POPE in the sodium alginate matrix promoted the development of opaque red films, with a content of phenolic compounds 43 times greater than the film without extract. As expected, the incorporation of POPE increased the antioxidant activity and the thickness of the alginate-based films. In addition, the incorporation of phenolic compounds promoted better interaction between the polymeric networks, reducing the water solubility of the alginate films. The results indicated that the sodium alginate films incorporated with several concentration of POPE have been shown to be an interesting material for the production of active packaging, being possible to apply them in foods with high water activity or susceptible to lipid oxidation, to preserve and extend the shelf life of these products. • Phenolic extracts from the purple onion peel were obtained and incorporated on alginate-based films. • Changes in the mechanical, physical and barrier properties of the alginate-based films were observed. • Alginate films functionalized with purple onion peel extract showed lower solubility. • High antioxidant activity was obtained by adding the phenolics extracts in alginate films. • Films can be used to reduce oxidation and increase the shelf life of food products.

Model of Chronic Thromboembolic Pulmonary Hypertension in Rats Caused by Repeated Intravenous Administration of Partially Biodegradable Sodium Alginate Microspheres

Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare and life-threatening complication of pulmonary embolism. As existing animal models of CTEPH do not fully recapitulate complex disease pathophysiology, we report a new rat model for CTEPH evoked by repetitive embolization of the distal pulmonary artery branches with partially biodegradable alginate microspheres (MSs). MSs (180 ± 28 μm) were intravenously administered eight times at 4-day intervals; control animals received saline. The validity of the model was confirmed using transthoracic echocardiography, exercise testing, catheterization of the right ventricle, and histological examination of the lung and heart. The animals in the CTEPH group demonstrated a stable increase in right ventricular systolic pressure (RVSP) and decreased exercise tolerance. Histopathological examination revealed advanced medial hypertrophy in the small pulmonary arteries associated with fibrosis. The diameter of the main pulmonary artery was significantly larger in the CTEPH group than in the control group. Marinobufagenin and endothelin-1 serum levels were significantly elevated in rats with CTEPH. In conclusion, repetitive administration of alginate MSs in rats resulted in CTEPH development characterized by specific lung vasculature remodeling, reduced exercise tolerance, and a persistent rise in RVSP. The developed model can be used for pre-clinical testing of promising drug candidates.

Polymer Nanorings with Uranium Specific Clefts for Selective Recovery of Uranium from Acidic Effluents via Reductive Adsorption

Nanostructured polymeric materials, functionalized with an appropriate receptor, have opened up newer possibilities for designing a reagent that shows analyte-specific recognition and efficient scavenging of an analyte that has either a detrimental influence on human physiology and environment or on its recovery for further value addition. Higher active surface area, morphological diversity, synthetic tunability for desired surface functionalization, and the ease of regeneration of a nanostructured material for further use have provided such materials with a distinct edge over conventional reagents. The use of a biodegradable polymeric backbone has an added significance owing to the recent concern over the impact of polymers on the environment. Functionalization of biodegradable sodium alginate with AENA (6.85% grafting) as the receptor functionality led to a unique open framework nanoring (NNRG) morphology with a favorable spatial orientation for specific recognition and efficient binding to uranyl ions (U) in an aqueous medium over a varied pH range. Nanoring morphology was confirmed by transmission electron microscopy and atomic force microscopy images. The nanoscale design maximizes the surface area for the molecular scavenger. A combination of all these features along with the reversible binding phenomenon has made NNRG a superior reagent for specific, efficient uptake of UO22+ species from an acidic (pH 3-4) solution and compares better than all existing UO22+-scavengers reported till date. This could be utilized for the recovery of uranyl species from a synthetic acidic effluent of the nuclear power. The results of the U uptake experiments reveal a maximum adsorption capacity of 268 mg of U per g of NNRG in a synthetic nuclear effluent. X-ray photoelectron spectroscopy studies revealed a reductive complexation process and stabilization of U(IV)-species in adsorbed uranium species (U@NNRG).

Effect of gum ghatti on physicochemical and microstructural properties of biodegradable sodium alginate edible films

Sodium alginate (SA) limits its application due to its low stability and poor performance. This study explored the synergy between SA and gum ghatti (GG) to improve the performance of biodegradable SA film. In this study, the chemical structure, rheological properties, morphology, thermal stability, and physical properties of the films were evaluated. Attenuated Total Reflection Fourier Transform Infrared Spectroscopy analysis (FTIR-ATR) revealed that hydrogen bonds are established between SA and GG, as well as strong electrostatic interactions. scanning electron microscopy and X-ray diffraction confirmed that SA has good compatibility with GG. Differential scanning calorimetry data demonstrated the excellent thermal properties of the SA/GG blend films. The film with an SA/GG ratio of 5:1 exhibited an elongation at break (EB), tensile strength (TS) and water vapor permeability (WVP) of 15.27% and 34.11 MPa and 7.19 × 10−11 g/(m s Pa), respectively. In addition, the light barrier properties of the blend film were improved 65.17%. Thus, there is a strong interaction between SA and GG to improve the properties of the blend films. SA/GG blend films offer wide application prospects as packaging materials and biomaterials in food industries.

Design and therapeutic application of sodium alginate-based hydrogel with biodegradability and catalytic activity

How to efficiently treat cancer in a minimally invasive manner has become one of the major focuses of recent developments in biomedicine. In this research, biodegradable sodium alginate (SA) hydrogel encapsulated with NaHCO3 and glucose oxidase (GOX) was synthesized using Fe3+ as the crosslinker for the tumor chemodynamic therapy (CDT) and starvation therapy (ST). Material safety assessments revealed that this hydrogel possesses good in vitro and in vivo security. In tumor microenvrionment (TME), the Fe3+ further reacted with the intracellular glutathione and was transformed into Fe2+, which triggered the Fenton reaction with the H2O2 within TME and produced abundant highly toxic ·OH (hydroxyl radicals) for efficient tumor CDT. Furthermore, the GOX catalyzed the enzymolysis of glucose to consume the nutrient of the tumor and enhance the H2O2 level in TME. Besides, the CO2 bubbles that were generated from the decomposing of NaHCO3 promoted the contact between glucose and GOX. Findings in this research would have important implications for the present status of tumor therapy.

A green method to prepare magnetically recyclable Bi/Bi25FeO40-C nanocomposites for photocatalytic hydrogen generation

In the present work, magnetically recyclable Bi/Bi25FeO40-C nanocomposites were synthesized through a one-step hydrothermal approach and then analyzed. The analysis results manifested that non-toxic and biodegradable sodium alginate takes a key role in successful preparation of Bi/Bi25FeO40-C. Sodium alginate can totally suppresses the formation of BiFeO3 because it changes the alkalinity of the medium, and at the same time Fe precursor greatly restrains the reduction of Bi3+ to Bi by sodium alginate, so the final product is Bi/Bi25FeO40 with a small amount of Bi instead of Bi, BiFeO3 or Bi/BiFeO3. Bi/Bi25FeO40-C showed enhanced photocatalytic activity in hydrogen generation as compared with pure Bi25FeO40 due to the surface plasmonic resonance effect of Bi and electron conductivity of carbon, which promote electron-hole separation and light absorption of the Bi/Bi25FeO40-C, resulting in high photocatalytic efficiency. The Bi/Bi25FeO40-C even exhibited higher catalytic efficiency than noble metallic nanoparticles and good reusability in p-nitrophenol reduction. This work provides a green way to prepare Bi/Bi25FeO40-C for catalytic reactions.

Influence of PH on the properties of sodium alginate films with norbixin salt

Environmental pollution caused by synthetic packaging materials has increased interest in biodegradable polymers. Sodium alginate is a linear polymer with the ability to form biodegradable films with good mechanical properties. Norbixin is a carotenoid with hydrophilic character and antioxidant properties that can be incorporated in the polymeric matrix. This work's objective was to evaluate the influence of pH (3.0, 7.0, and 11.0) on the properties of biodegradable sodium alginate films with norbixin salts. The pH did not influence water solubility, hydration capacity, colorimetric parameters, thermal properties, and the migration of the pigments into acidic aqueous solutions. The film prepared with pH 11.0 showed a more cohesive structure, with better sodium alginate-norbixin interaction. In addition, it showed lower water activity, higher tensile strength, and higher pigment migration in the lipid medium and good antioxidant activity in sunflower oil stored at accelerated conditions for up to 3 days. Practical applications Although biodegradable films are not intended to completely replace traditional synthetic packaging, they have the potential to reduce their use, in addition to acting as controlled release systems for bioactive compounds. The use of alternative materials, such as polysaccharides with the incorporation of carotenoids, allows biodegradable packaging to be obtained which has functional properties to preserve food quality and prolong its shelf life. The sodium alginate films with norbixin added can be used as packaging for foods with a high lipid content and susceptible to oxidation, in order to improve their stability during storage.

Biodegradable sodium alginate films incorporated with norbixin salts

AbstractPlastic packaging derived from petroleum may have a negative impact on the environment when it is not properly recycled. Some studies present the use of biodegradable packages developed from natural polymers as a sustainable alternative; thus, the present work aimed to develop biodegradable sodium alginate films with antioxidant properties by the incorporation of carotenoid norbixin. Norbixin salts at the concentration of 0.01–0.05% were added to the sodium alginate films complexed with calcium ions. Carotenoid incorporation did not significantly impacted with the moisture content and the swelling capacity of the films. The thickness, water activity, and solubility were higher in the films with 0.05% addition of norbixin salts. The presence of the carotenoid improved the thermal stability of the films, as well as the water vapor barrier properties and lower ultraviolet–visible light transmission. However, the incorporation of 0.03% norbixin salts showed the best result for the analysis of antioxidant activity, with lower formation of oxidation products during sunflower oil storage and potential application for high fat foods.Practical ApplicationsResearchers aim to replace synthetic packaging by eco‐friendly packaging. The use of alternative materials such as polysaccharides, proteins, and lipids has been studied for the production of packaging susceptible to degradation under environmental conditions. Thus, the present work developed sodium alginate films complexed with calcium and incorporated with norbixin salts able to decrease sunflower oil oxidation.

Antibacterial Porous Microcarriers with a Pathological State Responsive Switch for Wound Healing.

In this article, novel antibacterial porous microcarriers with a pathological state responsive switch were developed to promote wound healing. The porous microcarrier includes an inverse opal scaffold generated by a temperature-responsive hydrogel that deforms according to different temperatures and a biodegradable sodium alginate hydrogel used as a vehicle to load drugs. Thus, the microcarrier is endowed with the ability of releasing loaded drugs when the temperature changes in the wound site due to an inflammation reaction. Without inflammation, the microcarriers will be locked and the release of drug molecules will not continue, which prevents the abuse of drugs and further improves the safety of the therapeutic treatment. The designed microcarriers could eliminate inflammation significantly and promote the formation of granulation tissue, angiogenesis, and collagen deposition in the wound site. These features indicate that these microcarriers with a pathological state responsive switch are ideal for promoting wound healing and will have a great potential in biomedical applications.