Fabrication of a Cellulose-Based Wound Dressing Membrane from Sugarcane Bagasse Biowaste

Abstract

Plant-based biopolymers are considered biocompatible and nontoxic. In this work, a cellulose membrane was fabricated from sugarcane bagasse and characterized physicochemically and biologically. The structural study by Fourier-transform infrared spectroscopy and thermogravimetric analysis confirmed that the fabricated membrane was mainly composed of cellulose. The membrane could rapidly absorb water with a swelling ratio of approximately 600% in the first 60 min. Biodegradation evaluation revealed that the membrane degraded as time passed, with a weight loss of 11% at day 28 of the study. For the biocompatibility evaluation, results showed that the fabricated membrane could support human dermal fibroblast proliferation. The primary toxicity test (in vitro) indicated nontoxic potential of the fabricated cellulose membrane. An in vivo skin irritation test was performed on rabbit skin. After 72 h, no sign of irritation (edema or erythema) was observed. Results suggest the potential use of the fabricated cellulose membrane for wound dressing application.

1. Introduction

The advances in biomedical technology have enabled more effective and accessible treatments across various medical disciplines. In patients suffering from skin injuries, wound dressings play a pivotal role in protecting wounds, preventing infections, and supporting the healing process. An ideal wound dressing must be biocompatible, nontoxic, nonallergenic, and capable of maintaining a moist environmentconsidered optimal for tissue regeneration and pain reduction. It should absorb wound exudate, reduce trauma to healing tissues, and promote cellular proliferation and matrix production, thereby accelerating healing. −

Various types of wound dressings are available, including traditional gauze, hydrocolloids, hydrogels, foams, transparent films, alginate-based dressings, and bioactive collagen-based dressings. The choice depends on the type, size, severity, and anatomical location of the wound. − For example, hydrocolloids are suited for pressure ulcers or necrotic wounds, hydrogels for painful or infected wounds, alginates for heavy exudates, and transparent films for wounds requiring visual monitoring. While gauze is widely used due to its cost-effectiveness and biocompatibility, it tends to adhere to wounds and cause discomfort during removal due to dehydration. ,−

Wounds can be classified as acute or chronic based on the duration and healing response. Acute wounds typically heal within 8–12 weeks under proper care, whereas chronic wounds fail to heal due to underlying conditions such as diabetes or improper treatment. Wounds may also be categorized by typesuch as necrotic, burning, infected, or draining woundseach requiring specific care strategies. Wound healing itself progresses through four overlapping phases: coagulation/hemostasis, inflammation, proliferation, and maturation. −

In recent years, the use of natural polymers in wound dressing development has gained attention due to their biocompatibility, biodegradability, and environmental friendliness. These polymers mimic the extracellular matrix (ECM) structure, enhancing cell adhesion, proliferation, and function. Among these, cellulose stands out for its strength, hydrophilicity, and ability to form membranes with moisture retention and fluid absorption properties. − Bacterial cellulose is highly pure and widely used in biomedical applications, whereas plant-based cellulose, such as from sugarcane bagasse (SB), requires pretreatment to remove lignin and hemicellulose. −

SB, the fibrous byproduct of sugarcane processing, is a widely available agricultural waste in tropical countries such as Thailand. It is primarily used as a fuel source, in fiberboard production, and in the paper and fertilizer industries. Chemically, SB is composed mainly of cellulose (40–50%) and hemicellulose (30–40%), along with lignin, ash, and wax. − Due to its high cellulose content and availability, SB presents a promising raw material for the production of wound dressing membranes.

In this study, we developed a cellulose-based resorbable membrane from SB biowaste for wound dressing application. The characterization of the SB-derived cellulose membrane in terms of surface properties, chemical compositions, thermal and swelling behaviors, in vitro degradation, as well as primary cytotoxicity and in vivo skin irritation tests were performed.

2. Materials and Methods

2.1. Fabrication of the SB-Derived Cellulose Membrane

SB was ground into small pieces and submerged in distilled water for 24 h to remove contamination. After being air-dried for 24 h, 4%v/v H₂SO₄ acid solution was added and stirred for 2 h. Samples were rinsed with distilled water 5 times, followed by the addition of 10% NaOH solution, and stirred for 12 h using a magnetic stirrer. Samples were rinsed with distilled water until reaching a neutral pH prior to bleaching with 10% v/v NaOCl solution for 4 h. For cellulose membrane preparation, samples were put into dimethylacetamide/lithium chloride (DMAc/LiCl) solution (RCI Labscan Limited, Thailand) and stirred at room temperature for 3 days until the cellulose fibers dissolved. The acquired solution was poured into a Petri dish and dried in a hot-air oven at 80 °C for 3 days to fabricate the cellulose membrane.

2.2. Physicochemical Characterization of the SB-Derived Cellulose Membrane

2.2.1. Morphology

The morphological characterization of the SB membrane was performed using scanning electron microscopy (SEM; Quanta 250 microscope, FEI, OR, USA). Specimens were coated with gold using a sputtering device (JFC-1100E, JEOL, Tokyo, Japan) prior to SEM observation. Images were obtained after each evaluation.

2.2.2. Fourier-Transform Infrared (FTIR) Spectroscopy

The chemical functional groups of the SB membrane were evaluated using an FTIR spectrometer (Spectrum One, PerkinElmer, MA, USA). Spectra were measured as attenuated total reflectance (ATR) at room temperature in the spectral range of 400–4000 cm^–1 with a resolution of ±4 cm^–1 and a scan frequency of 32 times.

2.2.3. Thermal Behavior Analysis

The thermal behavior of the SB membrane was studied by differential scanning calorimetry (DSC; DSC 204 F1 Phoenix, NETZSCH Selb, Germany). Samples were placed in aluminum pans and purged with nitrogen gas at a flow rate of 40 mL/min. The heating temperature was set between 25 and 250 °C with a heating rate of 10 °C/min. Thermal degradation was examined using a thermogravimetric analyzer (TG 209 F3 Tarsus, NETZSCH). The heating temperature was set between 30 and 600 °C with a heating rate of 10 °C/min.

2.2.4. Swelling Behavior

The swelling behavior of the membranes was evaluated by immersing samples in distilled water at room temperature for 24 h. At predetermined intervals, samples were collected, gently blotted with filter paper to remove surface water, and weighed to determine the wet weight (W _s) using an analytical balance. The samples were then dried in a hot-air oven at 50 °C for 30 min to obtain the oven-dried weight (W _d), reimmersed in distilled water for 1 h, and the measurement steps were repeated until the swelling reached equilibrium.

Since thermogravimetric analysis (TGA) revealed a substantial residual water content (∼45%) in the oven-dried membranes, the true polymer dry mass (W _d,corr) was corrected as follows:

$$W_{\mathrm{d},\mathrm{corr}}=(1-r)W_{\mathrm{d}}$$

where r is the residual water fraction determined from TGA (mass loss between 25 and 160 °C).

The corrected swelling ratio (S _corr) was then calculated as follows:

$$S_{\mathrm{corr}}(\%)=\frac{W_{\mathrm{s}}-W_{\mathrm{d},\mathrm{corr}}}{W_{\mathrm{d},\mathrm{corr}}}\times 100$$

2.2.5. In Vitro Degradation

Membranes with a known weight (W ₀) were submerged in pH 7.4 phosphate buffer saline (PBS) solution (Gibco BRL, CA, USA) at room temperature for 1, 3, 5, 7, 14, 21, and 28 days. At each time point, samples were collected, placed on filter paper to discard excess water, and weighed (W _t). The percentage of in vitro degradation was calculated by using the following equation:

$$\mathrm{Degradation}(\%)=\frac{W_0-W_{\mathrm{t}}}{W_0}\times 100$$

2.3. Cell Behavior and Cytotoxicity Evaluation

2.3.1. In Vitro Primary Cytotoxicity and Proliferation Assay

An indirect cytotoxicity test was performed according to ISO 10993-5. The membrane was sterilized using UV light for 30 min, cut into small pieces (15 mm in diameter), and placed into a 24-well culture plate containing culture medium (0.5 mL/well), which was Dulbecco’s modified Eagle’s medium (Hyclone, Logan, UT, USA) supplemented with 10% fetal bovine serum (Gibco), 1% l-glutamine (Gibco), 100 units/mL penicillin (Gibco), 100 μg/mL streptomycin (Gibco), and 5 μg/mL amphotericin B (Gibco). After 24 h, the medium was collected. Human dermal fibroblasts (HDFa) (ATCC, VA, USA) were cultured at a density of 20,000 cells per well in 96-well plates and incubated at 37 °C in a 5% CO₂ humidified chamber overnight. Afterward, the medium in each well was replaced with 100 μL of the releasing medium (at concentrations of 0.5, 5, and 10 mg/mL), and the plates were further incubated for 24 h at 37 °C. The number of viable cells was measured using the 4,5-(dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay (USB Corporation, Cleveland, OH, USA) according to the manufacturer’s instructions. Viable cells are capable of converting yellow tetrazolium salt into purple formazan crystals using dehydrogenase enzyme. The optical density (OD) was observed at 570 nm using an absorbance microplate reader (SpectraMax M5; Molecular Devices, MA, USA). A 2D cell culture in normal conditions was used as the control.

The direct cytotoxicity (proliferation assay) was also determined. Membranes were sterilized with UV light for 30 min and placed in a 48-well plate containing the culture medium. Human dermal fibroblast cells were cultured at a density of 20,000 cells per well and incubated at 37 °C in a 5% CO₂ humidified chamber. The number of viable cells was measured at 2, 4, 24, 48, and 72 h using the MTT assay for the in vitro cell proliferation. The OD was observed at 570 nm using an absorbance microplate reader (SpectraMax M5; Molecular Devices). A 2D cell culture in normal conditions served as the control.

2.3.2. In Vivo Skin Irritation Test

The skin irritation test was performed according to ISO 10993-23:2021, Biological evaluation of medical devices Part 23: Tests for irritation and ISO 10993-12:2021, Biological evaluation of medical devices Part 12: Sample preparation and reference material. All procedures and animal care were approved by the Institutional Animal Care and Use Committee of the Thailand Institute of Scientific and Technological Research (TISTR) (animal use protocol no. TS-66001) and conducted by InnoHERB: Expert Centre of Innovative Herbal Products, TISTR. Three 11-week-old male New Zealand white rabbits (Oryctologus cuniculus) were used. Rabbits were housed individually in separated cages under a standard environment and feeding procedure. The weight of the rabbits was recorded at the beginning of the experiment, on day 7, and on day 14. All rabbits were shaved at the dorsal area to a shape of around 10 × 15 cm² 4–24 h prior to the skin test. Membranes were cut into a square shape of 2.5 × 2.5 cm², placed onto the shaved skin sites, and covered with dressing tape (Micropore, 3M, 3M Thailand) and self-adherent wrap (Coban, 3M). Sterilized gauzes were used as controls. Each rabbit received four patches: two SB tested membranes and two sterilized gauzes. After 24 h, all dressings were removed, and the skin was rinsed with warm water and patted dry. Rabbit skin was observed for any abnormality (erythema or edema) and scored according to the scoring criteria (Table ) at 24, 48, and 72 h. The primary irritation index (PII) was calculated from the abnormalities observed at 24, 48, and 72 h. The PII of each rabbit was calculated from the total skin irritation score divided by 6 (2 sites, 3 time points). The PII of the SB membrane was calculated from the summation of PII of each rabbit divided by 3 (3 rabbits) and then subtracted with the PII of sterilized gauze. The severity of irritation was classified from the PII score (Table ). All rabbits were euthanized at day 14 with an overdose of thiopental injection.

1. Scoring Criteria for Skin Irritation.

Reaction		Score
Erythema and eschar formation	No erythema	0
	Very slight erythema (barely perceptible)	1
	Well-defined erythema	2
	Moderate-to-severe erythema	3
	Severe erythema (beet to crimson red) to slight eschar formation (injuries in depth)	4
Edema formation	No edema	0
	Very slight edema (barely perceptible)	1
	Slight edema (edges of area well-defined by definite raising)	2
	Moderate edema (raised ∼ 1 mm)	3
	Severe edema (raised more than 1 mm and extending beyond area of exposure)	4
Maximum irritation score		8

2. Primary Irritation Index.

PII Score	Severity of irritation
0–0.4	Non-irritating
0.5–1.9	Slightly irritating
2.0–4.9	Moderately irritating
5.0–8.0	Severely irritating

3. Results

3.1. Characterization of the SB Membrane

3.1.1. Morphology

The SB membrane appeared as a translucent, flexible sheet with a whitish color and slight surface irregularities (Figure A). Its thickness ranged between approximately 0.2 and 0.5 mm. The overall appearance suggests successful film formation with a reasonable homogeneity. The surface morphology, examined via SEM at 1000× magnification, revealed a fibrous and layered structure (Figure B). The membrane showed aligned fibrous regions with occasional voids and pores, likely resulting from partial fiber aggregation and water evaporation during drying. These microstructural features indicate an uneven but interconnected surface network, which may influence the physical characteristics of the membrane, including fluid interaction and porosity.

1.

(A) Morphology and (B) SEM image of the cellulose membrane fabricated from SB.

3.1.2. FTIR Spectroscopy

The chemical composition and structure of the SB membrane were characterized by FTIR spectroscopy. Peaks were detected at 3274, 2898, 1729, 1380, 1321, 1157, 1031, and 899 cm^–1 (Figure ).

2.

FTIR spectrum of the cellulose membrane derived from SB.

3.1.3. Thermal Behavior Analysis

The thermal properties of the SB membrane were investigated using DSC, and the resulting thermogram is shown in Figure A. An initial broad endothermic peak was observed around 90–100 °C, followed by a relatively flat region up to approximately 250 °C and a sharp exothermic peak detected between 290 and 310 °C. TGA was performed to evaluate the thermal stability and residual moisture in the dried membranes. A significant initial weight loss (∼45%) was observed from room temperature to around 160 °C (Figure B). The second phase of weight loss (approximately 25%) occurred at around 180–390 °C. After that, the membrane weight was constant, with a degradation rate of around 4%, and the remaining weight was about 26% at 600 °C.

3.

(A) DSC and (B) TGA analyses of the cellulose membrane derived from SB.

3.1.4. Swelling Behavior

The SB-derived cellulose membranes demonstrated a high capacity for water absorption. During the first 60 min, the swelling ratio rapidly increased to approximately 627% after TGA correction (equivalent to ∼334% in the uncorrected calculation; Supporting Information) (Figure A). The absorption rate then gradually declined, and equilibrium swelling was reached after ∼400–480 min, with a corrected swelling ratio of ∼845% (previously ∼420% before correction). The swelling values remained stable up to 1440 min, indicating that the membranes maintained structural integrity and water retention throughout the experiment.

4.

(A) Swelling ratio and (B) in vitro biodegradation of the cellulose membrane derived from SB.

3.1.5. In Vitro Biodegradation

The in vitro biodegradation of the membrane was assessed by measuring the weight loss in PBS (pH 7.4) over a period of 28 days (Figure B). The membrane exhibited a gradual increase in weight loss with time, indicating a progressive hydrolytic degradation. An initial weight loss of 2.96% was observed on day 1, which increased to 5.52% at day 3 and 6.53% at day 7. At days 14 and 21, the degradation reached 7.93 and ∼9.51%, respectively. By the end of the study (day 28), the weight loss was 10.92% of the original dry weight.

3.2. Cellular Behavior Evaluation and In Vivo Skin Irritation Test

3.2.1. In Vitro Primary Cytotoxicity and Proliferation Assay

Indirect cytotoxicity test was performed using the MTT test. Results showed that the percentages of HDFa viable cells in the groups cultured with the SB membrane extracts at concentrations of 2.5, 5, and 10 mg/mL were 106.2 ± 1.7, 104.4 ± 2.6, and 100.0 ± 0.8%, respectively, when compared to the normal 2D control group (100%). The numbers of viable cells in all experimental groups were slightly different from that in the 2D control group, with no statistical significance (Figure A). The proliferation assay showed that the proliferative ability of HDFa cells cultured on the SB membrane was lower than that of the 2D control culture at 4 h. A significant difference was observed at days 1 and 2 of the experiment. However, when reaching the end of the experiment at 72 h (day 3), the proliferative ability of all groups did not significantly differ (180.8 ± 4.0% for the membrane group and 195.0 ± 1.0% for the control), as shown in Figure B.

5.

(A) MTT results showing similar HDFa cell viability percentages in all groups. (B) Attachment and proliferation of HDFa cells when cultured on the SB membrane.

3.2.2. In Vivo Skin Irritation Test

The skin irritation test was conducted using a rabbit model. The weight of rabbits was recorded at the beginning (day 0), on day 7, and on day 14 of the experiment. All rabbits gained weight as time passed (Table ). For the skin irritation test, no sign of irritation, including erythema or edema, was observed at all time points, except for one very slightly red erythema expression in rabbit no. 2 with the SB membrane at 24 h, which eventually disappeared when observed at 48 h. The PII indicated the rabbit dermal reaction with the tested sample. The calculated PII is shown in Table . The PII values of the SB membrane were about 0.06 where as PII values of quaze were 0. All animals appeared normal and healthy, with no morbidity throughout the experiment.

3. Recorded Weight (g) of Rabbits.

Rabbit	day 0	day 7	day 14
Rabbit 1	2556.93	2709.27	2885.32
Rabbit 2	2857.99	3030.76	3123.00
Rabbit 3	2797.48	2951.32	3108.55
Mean ± SEM	2737.47 ± 91.94	2897.12 ± 96.68	3038.96 ± 76.93

4. Skin Irritation Score and PII of the SB Membrane.

		Score (SB membrane)						Score (gauze/control)
		Rabbit 1		Rabbit 2		Rabbit 3		Rabbit 1		Rabbit 2		Rabbit 3
time		SB1	SB2	SB1	SB2	SB1	SB2	C1	C2	C1	C2	C1	C2
24 h	Erythema	0	0	0	1	0	0	0	0	0	0	0	0
	Edema	0	0	0	0	0	0	0	0	0	0	0	0
	Total Score	0	0	0	0	0	0	0	0	0	0	0	0
48 h	Erythema	0	0	0	0	0	0	0	0	0	0	0	0
	Edema	0	0	0	0	0	0	0	0	0	0	0	0
	Total Score	0	0	0	0	0	0	0	0	0	0	0	0
72 h	Erythema	0	0	0	0	0	0	0	0	0	0	0	0
	Edema	0	0	0	0	0	0	0	0	0	0	0	0
	Total Score	0	0	0	0	0	0	0	0	0	0	0	0
Mean PII (rabbit)		0		0.17		0		0		0		0
PII score		0.06						0

4. Discussion

Biopolymers from natural polymers or biowastes are being developed to be used as wound dressing materials, as they are biocompatible, biodegradable, and more environmentally friendly than synthetic polymers. Because of their hydrophilicity, biopolymers possess excellent biocompatibility and support cellular proliferation and differentiation. A number of natural polymers can be used to fabricate wound dressings, for example, collagen, chitin, alginate, cellulose, and silk fibroin. − Cellulose-based wound dressings are biocompatible, biodegradable, and able to provide a moist wound environment, which supports wound healing. These dressings can absorb the exudate and protect the wounds against pathogens, preventing further infections or complications. For these reasons, cellulose-based dressings are suitable for several wound types, including burns, ulcers, and acute or chronic wounds. − Bacterial cellulose is well acknowledged for its purity without contamination with hemicellulose or lignin. With the good biocompatibility, high strength, and water absorption ability, it is appropriate for biomedical applications such as scaffolds for tissue engineering or wound dressing. Plant-based cellulose, on the other hand, consists of hemicellulose or lignin and needs to be purified prior to the application. −

SB is a common biowaste found throughout Thailand and tropical countries. It is commonly used as the main fuel in biomass electricity production, fiber board or particle board production, paper and packaging industries, and fertilizers in agriculture. SB (dry weight) mainly consists of cellulose (40–50%) and hemicellulose (30–40%), with lignin (18.1%), ash (2.3%), wax (0.8%), and other components (0.7%). − In this study, we successfully developed and characterized a cellulose wound dressing membrane from SB. The cellulose membrane was around 0.2–0.5 mm thick, which was appropriate to be used in a wound dressing applications. The smooth surface of the membrane indicated the homogeneity of the cellulose solution that was extracted from SB. The wavelike pattern on the membrane surface possibly occurred from the fabrication process. SEM images revealed a fibrous and layered surface morphology, which indicates the successful formation of a continuous membrane structure. While these morphological features may influence the porosity and fluid interaction, the mechanical performance and wound dressing suitability cannot be inferred solely from the SEM analysis. Further mechanical and biological evaluations are required to determine the potential of the membrane for biomedical applications.

The FTIR spectrum of the SB membrane is presented in Figure . Characteristic peaks indicate the presence of cellulose-based components. A broad absorption band at 3274 cm^{– 1} corresponds to O–H stretching, and a peak at 2898 cm^{– 1} is attributed to C–H stretching vibrations. The strong band observed at 1031 cm^{– 1} is assigned to C–O stretching, while the band at 899 cm^{– 1} is indicative of β-glycosidic linkages, both confirming the presence of cellulose. The absorption band at 1729 cm^{– 1}, however, corresponds to CO stretching vibrations, which may arise from acetyl or uronic ester groups in the hemicellulose or carbonyl groups present in residual lignin, as previously reported. Therefore, this peak suggests that small amounts of lignin or hemicellulose components may still be presented in the SB-derived membrane. Additional peaks at 1380, 1321, and 1157 cm^{– 1} can be attributed to C–H bending, O–H bending, and asymmetric C–O–C stretching, respectively. These peaks are commonly observed in cellulose-rich materials.

The thermal behavior of the SB-derived cellulose membrane revealed good thermal stability. For DSC, the initial endothermic peak around 90–100 °C is likely attributed to the loss of physically adsorbed water and moisture content. This is typical for lignocellulosic biomaterials such as cellulose and hemicellulose, which can retain bound water due to their hydrophilic components. A relatively flat region up to approximately 250 °C indicated the thermal stability of the membrane in this range. No distinct glass-transition temperature (T _g) was observed, which may be due to the complex heterogeneous structure of SB that is composed of amorphous and semicrystalline components such as cellulose, hemicellulose, and lignin. A sharp exothermic peak around 290–310 °C might correspond to the thermal degradation of the organic components, primarily due to the breakdown of cellulose and lignin structures. This decomposition event reflects the onset of major structural degradation, consistent with the thermal behavior of other plant-based lignocellulosic materials. Thermal analysis (TGA) illustrated that the membrane weight decreased as the temperature increased, which was in accordance with da Luz et al. study. The significant weight loss (∼45%) observed between 25 and 160 °C is attributed primarily to the evaporation of adsorbed and physically bound water, as well as residual solvents or low-molecular-weight components. This confirms that despite air-drying and vacuum-drying, residual moisture remained within the membrane structure. This value was used to correct the swelling ratio to reflect the actual polymer weight, thereby ensuring accurate characterization of the swelling behavior. This thermal event is consistent with previous TGA studies of cellulose-based membranes. A second stage of weight loss occurred in the range of 160–380 °C, corresponding to the onset of cellulose and hemicellulose degradation. This stage is typically associated with depolymerization, dehydration, and decomposition of glycosyl units, which together contribute to approximately 25% additional mass loss. A slight mass loss in the final degradation phase (380–600 °C) probably occurred from the continued degradation of cellulose. Overall, the weight loss in this temperature range was minimal, which might be from the presence of inert carbon that remains stable at high temperatures. These results imply that the SB-derived cellulose membrane is thermally resistant and can be used or sterilized in high temperatures.

The corrected swelling data highlight the pronounced hydrophilic character of the SB-derived cellulose membranes. The initial rapid uptake followed by a plateau is consistent with the absorption behavior of cellulose-based biomaterials reported previously. ,− , The recalculated equilibrium swelling ratio of ∼845%obtained after excluding residual water content from the “dried” membranesdemonstrates that the true swelling capacity of the polymer matrix was significantly underestimated in the uncorrected values.

This high swelling capacity is advantageous for wound dressing applications as it enables the membrane to absorb the wound exudate effectively while maintaining a moist environment, which is known to accelerate the wound-healing process by promoting cell proliferation and migration and by reducing scab and scar formation. − Furthermore, the ability of the membranes to retain water over extended periods without further expansion or disintegration ensures stable performance and minimizes the risk of leakage. The corrected swelling results confirm that the SB-derived cellulose membranes possess excellent water absorption and retention properties, supporting their suitability as moisture-managing biomaterials for wound care applications.

The SB-derived cellulose membrane demonstrated a gradual and controlled biodegradation profile. An initial weight loss of 2.96% was observed after 1 day, which progressively increased to about 11% by day 28 (Figure B). The relatively low degradation rates over time indicate that the SB membrane is able to retain its structural integrity for extended periods, which can be attributed to the inherent stability of the cellulose backbone. Such a degradation behavior reflects a stable and predictable breakdown process, which is particularly advantageous for biomedical applications that require sustained material performance. Comparable findings have been reported for other cellulose-based biomaterials, which typically exhibit less than 15% weight loss over 28 days under hydrolytic conditions. , In this context, the SB membrane may serve as a suitable candidate for uses such as controlled drug delivery systems or long-term wound dressings, where gradual resorption and prolonged functionality are essential.

For biological evaluation, both in vitro and in vivo studies illustrated no toxic potential of the SB-derived cellulose membrane. According to ISO 10993-5, in vitro cytotoxicity of medical devices, the percentage of cell viability must be at least 70% when compared to the 2D control. These results indicated that the SB-derived cellulose membranes exhibited no cytotoxic effects, as the cell viability remained similar to that of the control group. The absence of significant cytotoxicity suggested that SB membranes are biocompatible and considered suitable for biomedical applications, such as wound dressings or tissue engineering, where cell viability is crucial for successful integration and function. Moreover, the membrane was able to support growth and proliferation of HDFa cells. In vivo skin irritation tests on rabbit skin also demonstrated no irritation or morbidity in the tested animals. The PII, which reflects the overall dermal response to the material, was calculated to be 0.06 for the SB membrane, indicating a nonirritating behavior according to the standard criteria. The absence of significant irritation signs and the low PII values (below 0.4 for all groups) imply that the SB-derived cellulose membrane is biocompatible and well-tolerated by the skin, making it a promising candidate for clinical applications such as wound dressings or other dermal interface devices.

5. Conclusions

The pivotal properties of wound dressing materials are biocompatibility with no toxicity. They should be hydrophilic and capable of absorbing blood or secretions. The fabricated SB-derived cellulose membrane exhibited appropriate properties to be used as a wound dressing. It was biodegradable and could rapidly absorb water. The membrane was biocompatible, had no potent toxicity, and could support the proliferation of human skin fibroblasts. No skin irritation or morbidity were observed in the rabbit skin irritation test. These findings underscore the potential use of cellulose-based materials, such as those derived from SB, as a safe and effective alternative biomaterial for healthcare applications.

The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/acsomega.5c04589.

• Methods of swelling behavior (S1); results and discussion of the swelling behavior (S2); swelling ratio of the cellulose membrane derived from SB (Figure S1) (PDF)

This work was supported by the Science, Research and Innovation Promotion Fund (SRIPF) through the Program Management Unit for Competitiveness Enhancement (PMU-C) (Grant No. C10F630266), the Faculty of Dentistry, Chulalongkorn University, and the Thailand Science Research and Innovation (TSRI), Chulabhorn Research Institute (Grant No. 53502/4821863).

The authors declare no competing financial interest.