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Heliyon 11 (2025) e42648
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Research article
Antimicrobial activity and biocompatibility of alpha-silver 
tungstate nanoparticles
Sarah Raquel de Annunzio a,*,1, Bruna de Lima Moraes b,1, Marcelo Assis c, Paula 
Aboud Barbugli a, Vinícius Henrique Ferreira Pereira de Oliveira a, Elson Longo d, 
Carlos Eduardo Vergani a
a São Paulo State University (UNESP), School of Dentistry, Araraquara, SP, Brazil
b São Paulo State University (UNESP), School of Pharmaceutical Sciences, Araraquara, SP, Brazil
c Department of Physical and Analytical Chemistry, University Jaume I (UJI), Castelló 12071, Spain
d CDMF, Federal University of São Carlos (UFSCar) 13565-905, São Carlos, SP, Brazil
A R T I C L E I N F O
Keywords:
Silver tungstate nanoparticles
Nanotechnology
Antimicrobial activity
Biocompatibility
A B S T R A C T
The growing global threat posed by microorganisms resistant to conventional antimicrobials 
underscores the urgent need for novel agents to control infections. The aim of this study was to 
evaluate the antimicrobial activity and biocompatibility of alpha-silver tungstate (α-Ag2WO4) 
nanoparticles (NPs) synthesized by the ultrasonic method. The NPs were characterized, and their 
antimicrobial activity was assessed against Candida albicans, Staphylococcus aureus, and Escher-
ichia coli using the broth microdilution method, determining the minimum inhibitory concen-
tration (MIC) and minimum bactericidal/fungicidal concentration (MBC/MFC). Intracellular 
reactive oxygen species (ROS) production was detected by fluorescence using the CM-H₂DCFDA 
probe. Cytotoxicity was evaluated using murine L929 fibroblasts by MTT assay. Cell viability of 
both microorganisms and L929 fibroblasts was further assessed using Confocal Laser Scanning 
Fluorescence Microscopy (CLSM). For C. albicans, the MIC was 3.90 μg/mL, and the MFC was 
7.81 μg/mL. For S. aureus, the MIC and MBC were both 62.50 μg/mL, while E. coli exhibited MIC 
and MBC values of 0.48 μg/mL. The biocompatibility assay revealed a significant reduction in cell 
viability at concentrations starting from 15.62 μg/mL. CLSM images corroborated the results from 
both microbiological and biocompatibility assays. Additionally, ROS production was detected in 
all three microorganisms upon exposure to the NPs, confirming their antimicrobial mechanism. In 
conclusion, α-Ag₂WO₄ NPs effectively inactivated C. albicans, S. aureus, and E. coli. However, a 
higher concentration was required to inhibit S. aureus compared to E. coli and C. albicans. The 
biocompatibility assay revealed concentration-dependent cytotoxic effects. These findings high-
light the potential of α-Ag2WO4 NPs as antimicrobial agents and suggest further research into 
their efficacy against biofilms, optimization of their biocompatibility, and the application of these 
nanomaterials in the incorporation and coating of materials used in biomedical and dental 
devices.
* Corresponding author.
E-mail addresses: sarah.annunzio@unesp.br (S.R. de Annunzio), bl.moraes@unesp.br (B. Lima Moraes), marcelostassis@gmail.com (M. Assis), 
paula.barbugli@unesp.br (P.A. Barbugli), vinicius.vhfpo@gmail.com (V. Henrique Ferreira Pereira de Oliveira), elson.liec@gmail.com
(E. Longo), carlos.vergani@unesp.br (C.E. Vergani). 
1 These authors contributed equally to this work.
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https://doi.org/10.1016/j.heliyon.2025.e42648
Received 14 May 2024; Received in revised form 12 January 2025; Accepted 10 February 2025 
mailto:sarah.annunzio@unesp.br
mailto:bl.moraes@unesp.br
mailto:marcelostassis@gmail.com
mailto:paula.barbugli@unesp.br
mailto:vinicius.vhfpo@gmail.com
mailto:elson.liec@gmail.com
mailto:carlos.vergani@unesp.br
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Heliyon 11 (2025) e42648
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1. Introduction
The emergence of microorganisms resistant to conventional antimicrobials has become a global threat to human health [1]. The 
escalating prevalence of antimicrobial-resistant and multidrug-resistant (MDR) microorganisms has intensified the search for new 
infection control agents [2–4]. Antimicrobial resistance stems from natural evolutionary processes involving genetic mutations or the 
acquisition of resistance genes from other microorganisms. These processes limit drug absorption, inactivate and/or efflux drugs, and 
alter the target of antimicrobials [5,6]. Often, these mechanisms are associated with the indiscriminate use of antimicrobials for the 
prevention and management of infections and associated diseases [7].
Antimicrobial-resistant and MDR microorganisms include Gram-positive and Gram-negative bacteria and fungi. Among Gram- 
positive bacteria, Staphylococcus aureus is a major pathogen responsible for a significant portion of invasive infections worldwide, 
contributing to 80 % of hospital infections [8]. This microorganism is associated with skin, cardiovascular, and pulmonary infections 
[9]. Escherichia coli, a Gram-negative bacterium, establishes commensal relationships with the gastrointestinal microbiota of verte-
brates, but can also cause infections in the urinary, abdominal, and pulmonary regions [10]. Candida albicans, a notable fungal species, 
is frequently found in the oral cavity and is considered an opportunistic pathogen that resides as a commensal in the human body. 
Imbalances in the host immune system can lead to superficial or invasive infections [11]. Furthermore, C. albicans is the most 
commonly isolated Candida species in patients with candidemia [12]. Consequently, the development of effective antimicrobials 
against these microorganisms is clinically relevant.
Nanotechnology has been used to develop novel materials with antimicrobial properties [7,13]. Throughout history, silver-based 
materials have been recognized for their antimicrobial properties [14,15]. However, silver nanoparticles (AgNPs) are known for their 
instability, aggregation tendency, and high toxicity [16,17]. To address these challenges, previous studies have explored materials 
containing silver, focusing on maintaining antimicrobial efficacy while enhancing biocompatibility. Silver-based semiconductors such 
as vanadates, molybdates, phosphates, and tungstates have gained attention due to their potent antimicrobial activity [18–21]. One 
material showing significant promise for advancing healthcare technologies is α-Ag2WO4, a semiconducting metallic oxide with a 
complex three-dimensional structure [22], typically appearing as microcrystals. Extensive research has validated its antimicrobial 
effect against methicillin-resistant S. aureus (MRSA), C. albicans, and E. coli [18,23–25]. Its mechanism of action involves the formation 
of ROS and the ionic release of Ag+ [26,27].
To enhance the antimicrobial activity of α-Ag2WO4, various synthetic strategies can be employed, particularly during the synthesis 
process. Macedo et al. [28] synthesized α-Ag2WO4 microcrystals using the SDS surfactant, resulting in cuboid microcrystals, while 
water-based synthesis yielded hexagonal microrod-like materials. Theoretical simulations revealed alterations in the (101) surface of 
hexagonal microrods compared with the (001) surface in cuboid morphologies. This surface stabilization contributed to a two-fold 
decrease in the antimicrobial activity of cuboid particles against MRSA. Another study by Laier et al. [29] demonstrated that con-
trolling the size of α-Ag2WO4, achieved through microwave irradiation, modulated the antimicrobial effect of this materialin its 
hexagonal microrod-like morphology. Foggi et al. [23] observed changes in the synthesis of α-Ag2WO4 microcrystals using water, 
ammonia solution, and alcoholic solution as solvents, resulting in alterations in the morphology and variations in antimicrobial 
effectiveness. This emphasizes the influence of surface type and stabilized surface amount on the antimicrobial properties of 
α-Ag2WO4.
One strategy rooted in the principles of nanotechnology involves the reduction of material size. This size reduction not only en-
hances the production of ROS and the release of Ag+ but also facilitates the material’s entry into the cell, thereby increasing the ef-
ficacy of this compound [1,7,13]. Recently, Ribeiro et al. [30] demonstrated that the utilization of different carboxylic acids during 
synthesis could control the size of this particle, although the antimicrobial efficacy of α-Ag2WO4 NPs needs to be established. In this 
context, the present study aimed to synthesize α-Ag2WO4 NPs and evaluate the interaction of these materials with different micro-
organisms and their biocompatibility.
2. Materials and methods
2.1. Synthesis and characterization of α-Ag2WO4 NPs
The α-Ag2WO4 NPs were synthesized utilizing the ultrasonic method [30]. To assess their properties, X-ray diffraction (XRD) and 
scanning electron microscopy (SEM) were employed. Furthermore, their behavior in solution was examined through dynamic light 
scattering (DLS), zeta potential analyses, and ion release studies. Details about the synthesis and characterization of α-Ag2WO4 NPs can 
be found in the Supplementary Materials.
2.2. Antimicrobial activity
Tests were performed using the broth microdilution method established by the Clinical and Laboratory Standards Institute (CLSI – 
M27 A2 and CLSI – M07 A9) [31,32]. Following the methodology established by Foggi et al. [23], concentrations ranging from 0.24 to 
125 μg/mL were evaluated. During the experiment, the NPs were weighed in sterile 1.5-mL microtubes using a precision scale and then 
dispersed in sterile deionized water at a concentration of 2 mg/mL. Subsequently, the tube underwent ultrasonication for 3 cycles, with 
each cycle lasting 8 min [33] to ensure optimal dispersion of the NPs. After dispersion, two 1:1 (v/v) dilutions were carried out in 
Roswell Park Memorial Institute medium (RPMI-1640; Sigma-Aldrich, St. Louis, MO, USA) or Mueller Hinton broth (MH; KASVI, 
S.R. de Annunzio et al. 
Heliyon 11 (2025) e42648
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Paraná, Brazil). As a result, the microtube containing the dispersed NPs used to start the serial dilutions attained the final concentration 
of 500 μg/mL. The NPs were serially diluted to obtain the desired concentrations. Subsequently, a 100 μL aliquot of the prepared 
Candida albicans (American Type Culture Collection (ATCC) 90028) suspension was added to each well containing the NPs for fungi. 
For bacteria, a 20 μL aliquot of the adjusted Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922) suspensions was 
added to each of the wells. Then, the plates were wrapped in plastic film to prevent evaporation and incubated in an oven at 37 ◦C for 
24 h. Following incubation, the MIC was determined by measuring the absorbance at 562 nm for C. albicans and 595 nm for bacteria 
using the EZ Read 400 microplate reader (Biochrom), with the aid of the Adapt 2.0 BioChrom software. The MIC was identified as the 
lowest concentration of NPs inhibiting microorganism growth. The MFC and MBC were determined by counting the number of 
colony-forming units (CFU/mL). The MFC and MBC were determined at the lowest concentration with no detectable colony growth. 
The experiment was performed in triplicate on three separate occasions (Supplementary Materials).
2.2.1. Confocal laser scanning fluorescence microscopy (CLSM)
The antimicrobial effect of α-Ag2WO4 NPs was also evaluated through CLSM (Carl Zeiss LSM 800 with Airyscan) using the LIVE/ 
DEAD BacLight™ Bacterial Viability Kit (Molecular Probes, OR, USA). Images were acquired using a CLSM at a 20 × magnification 
objective. The laser wavelength was set to 488 nm, and the laser ranges used for detection were 488–546 nm for Syto-9 (with a gain of 
685 V) and 561–700 nm for Propidium iodide (PI) (with a gain of 766 V) [34]. The tests were performed in quintuplicate (Supple-
mentary Materials).
2.2.2. Intracellular ROS quantification
Intracellular ROS production was quantified following established procedures Carmello et al. [35] The fluorescent probe 
CM-H2DCFDA (General Oxidative Stress Indicator, Thermo Fischer Scientific, Waltham, MA USA) was resuspended in 144 μL of 
ethanol (600 μM stock solution), and 2 μL was added to each well containing 200 μL of microorganism suspensions at 5 × 106 CFU/mL 
(probe final concentration: 6 μM) (supplementary material). Control cells containing only the culture medium and a control containing 
10 mM of H2O2 (Sigma-Aldrich) were also used. Fluorescence intensity was measured (Ex. 492 nm and Em. 520 nm) using a microplate 
reader (Synergy H1 multimode microplate reader, BioTek, Winooski, VT, EUA). The assays were performed in triplicate on three 
separate occasions.
2.3. Cell viability assay
Murine fibroblasts (L929) were used in this study [36,37]. The L929 fibroblast cells were resuspended in Dulbecco’s Modified Eagle 
Medium (low glucose, 1 g/L), counted in a Neubauer chamber, plated in a 96-well plate (30.000 cells per well), and incubated at 37 ◦C 
with 5 % CO2 for 24 h. To assess NP biocompatibility, the following concentrations were tested: 1.95, 3.90, 7.81, and 15.62 μL. Wells 
containing cells alone were used as positive controls (PC), and wells containing 0.1 % Triton-X were used as death controls (DCs). 
Thiazolyl blue tetrazolium bromide (MTT, Sigma-Aldrich) was prepared at a concentration of 1 mg/mL in RPMI broth without phenol 
red (Sigma-Aldrich). After 24 h of incubation with NPs, the culture medium was removed, and 100 μL aliquots of the previously 
prepared MTT solution were added to each of the wells containing the cells. The plates were incubated for 12 h. Subsequently, the MTT 
solution was removed from the wells, 150 μL of isopropyl alcohol (Synth, Diadema, SP, Brazil) was added to each well, and the content 
was transferred to another 96-well plate. Next, the absorbance at 562 nm was read on an EZ Read 400 microplate reader (Biochrom) 
using Adapt 2.0 Biochrom software. This experiment was performed in triplicate on three separate occasions (Supplementary 
Materials).
2.3.1. CLSM
Cell viability post-exposure to NPs was assessed using CLSM (Carl Zeiss LSM 800 with Airyscan) according to a protocol adopted in 
Pimentel et al.’s study [20]. The lasers used were 405 nm with detection up to 470 nm for the Hoechst 33342, 488 with detection up to 
530 nm for the ActinGreen™ stain, and up to 600 nm for the PI. The samples were analyzed at a 10 × magnification objective. The tests 
were performed in quintuplicate (Supplementary Material).
2.4. Statistical analysis
The data obtained underwent normality analysis (Shapiro-Wilk test). Statistical analyses of the MIC, intracellular ROS detection, 
and biocompatibility assays were performed using an analysis of variance test (one-way ANOVA) followed by Tukey’s post hoc test. For 
the MBC and MFC tests, the Kruskal-Wallis test followed by Dunn’s post hoc test was applied. All analyses were performed using 
GraphPad Prism® version 5.01 software (Graph Pad Software Inc., La Jolla, CA, USA). The significance level adopted for statistical 
tests was set at 5 % (pexhibit an orthorhombic structure and belong to the 
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Heliyon 11 (2025) e42648
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Pn2n space group, aligning with the crystallographic data number 248969 in the Inorganic Crystal Structure Database. The absence of 
additional peaks that were observed signifies the high purity of the synthesized NPs. To further investigate the size reduction of 
α-Ag2WO4, SEM images were acquired (Fig. 1B), confirming that the synthesized NPs display a nanorod morphology, with a length of 
122 ± 32 nm and a width of 24 ± 14 nm.
3.2. Ionic liberation, zeta potential, and particle size
Table 1 presents the values of Ag and W released into the water after 24 h of incubation under conditions identical to those used in 
subsequent cell cultures. The ionic release is dependent on the concentration of α-Ag2WO4 NPs, with a reduction in this release 
observed after reaching 15.62 μg/mL. The maximum values obtained for the concentration of 62.50 μg/mL were 1.82 and 1.69 ppm for 
Ag and W, respectively. The zeta potential of α-Ag2WO4 NPs dispersed in water at a concentration of 125 μg/mL was − 28.40 ± 0.4 mV 
at pH 7. To assess particle size and polydispersity index (PdI), the α-Ag2WO4 NPs were examined at a concentration of 125 μg/mL 
under three different conditions (Table 2). I. The samples were dispersed, and readings were performed. II. The samples were 
dispersed, incubated for 24 h at 37 ◦C, and redispersed in ultrasound, and reading was performed. III. The samples were incubated for 
24 h under the conditions described previously, washed three times with distilled water, redispersed, and analyzed. Significant ag-
gregation was not observed. The PDI results obtained were consistently similar, indicating uniform polydispersity (Table 2).
3.3. Antimicrobial activity
Antimicrobial assays were performed using the broth microdilution method. The MIC was determined at the α-Ag2WO4 NP con-
centration at which antimicrobial growth was not detected and the MFC or MBC at the concentration at which no colony growth was 
detected. In tests using C. albicans, the MIC value was 3.90 μg/mL; for other concentrations evaluated, the reduction in absorbance 
exhibited a significant difference compared with the PC (p 0.05). However, concentrations of 1.95 and 
3.90 μg/mL resulted in reductions of 2.75 (p 0.05). Inhibition of bacterial growth was 
noted from a concentration of 15.62 μg/mL. Concentrations of 7.81 and 15.62 μg/mL did not show significant reductions in colony 
counts compared with the PC (p > 0.05). However, the concentration of 31.25 μg/mL showed a reduction of 1.54 log 10 (p 0.05).
3.4. CLSM
The LIVE/DEAD assay revealed that the untreated controls of each microorganism exhibited viability, with cells stained in green 
(Fig. 3A–D, and G). Additionally, DCs were carried out, highlighting the presence of dead cells stained in red (Fig. 3B–E, and H). DCs 
were performed by treating C. albicans with 16 μg/mL of fluconazole and the bacteria with 0.06 % chlorhexidine gluconate. The images 
illustrate that suspensions treated with the NPs (1.95 μg/mL for C. albicans, 31.25 μg/mL for S. aureus, and 0.24 μg/mL for E. coli) align 
with the MIC and MBC/MFC tests, revealing a more pronounced reduction in the viability of C. albicans (Fig. 3C) and a lesser impact for 
Fig. 1. A) XRD and B) SEM images of the α-Ag2WO4 NPs.
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Heliyon 11 (2025) e42648
5
Table 1 
Ionic release of Ag and W at different concentrations of α-Ag2WO4 NPs.
Concentration (μg/mL) Concentration (ppm)
Ag W
62.5 2.12 3.29
31.25 1.97 2.04
15.6 1.82 1.69
7.81 0.81 0.94
3.9 0.41 0.614
1.95 0.24 0.33
0.97 0.11 0.09
0.48 0.03 0.056
Ppm: parts per million.
Table 2 
Mean and standard deviation of particle size values and PdI of α-Ag2WO4 NPs dispersed in aqueous medium.
Conditions Diameter (nm) PdI
I 189.25 (±0.64) ​ 0.292 (±0.01)
II 151.60 (±0.40) ​ 0.332 (±0.02)
III 150.55 (±1.34) ​ 0.252 (±0.01)
PdI: polydispersity index.
Fig. 2. Antimicrobial activity of α-Ag2WO4 NPs against suspensions of C. albicans, S. aureus, and E. coli treated with different concentrations of 
α-Ag2WO4 NPs. A) Mean absorbance values of C. albicans suspensions. The asterisks represent the statistical difference between groups and the 
positive control (PC). One-way analysis of variance with Tukey’s post hoc test. ***p 0.05). However,contact of cells with α-Ag2WO4 NPs at a concentration of 
15.62 μg/mL led to a decrease in cell viability compared with the PC (p 0.05) (Fig. 5A). According to the In-
ternational Organization for Standardization (ISO) 10993–5:2009 [36], inhibition of cell growth above 70 % indicates severe material 
toxicity.
3.7. CLSM
To qualitatively evaluate the L929 cells after contact with the NPs, the cells were labeled with ActinGreen™ 488 (cytoskeleton, in 
green), Hoechst 33342 (nucleus, in blue), and PI (cell death, in red) and were visualized under a CLSM (Fig. 5B). The PC shows the 
living PC cells stained in green and blue. The α-Ag2WO4 [7.81 μg/mL] figure represents the fibroblasts that were in contact with the 
NPs at a concentration of 7.81 μg/mL and are also viable. The cells in the DC group were stained in red, indicating non-viability 
(Figure DC). Similarly, in the image representing the cells that were in contact with the NPs at a concentration of 15.62 μg/mL, a 
reddish color was evident (α-Ag2WO4 [15.62 μg/mL] figure). These observations align with the MTT assay results, revealing a 
significant reduction in cell viability after contact with NPs at a concentration of 15.62 μg/mL.
4. Discussion
Infectious diseases are one of the main causes of mortality worldwide [13]. The emergence of antimicrobial-resistant and MDR 
strains poses a public health concern [1]. The appearance of these strains is attributed to the indiscriminate use of antibiotics and 
antifungals, leading to the evolution of new resistant microorganisms at a faster pace [5,6]. Recent applications of nanotechnology 
have led to the development of novel materials with antimicrobial properties [7]. NPs surpass conventional antimicrobial agents in 
terms of antimicrobial efficacy, owing to their high surface-area/volume ratio.
The precise mechanism of action of metal oxide NPs warrants further exploration; however, current understanding indicates that 
these materials predominantly engage in electrostatic interactions with the cell membrane, internalization, alterations, disruption of 
the cell wall, and disruption of enzymatic and nucleic acid due to ionic release or the production of ROS [38,39]. These mechanisms 
differ from those of the conventional antimicrobial agents. Cellular damage caused by metal oxide NPs in microorganisms occurs at 
both the biochemical and molecular levels. Thus, these NPs are promising antimicrobial agents [40,41].
In the present investigation, the negative zeta potential values of α-Ag2WO4 NPs imply a low affinity between the samples and the 
cell membrane, given their shared negative potentials. This poses a challenge for electrostatic interactions, especially at pH values 
close to the physiological levels. Consequently, mechanisms such as internalization and cell membrane disruption caused by the 
electrostatic interactions between the NP and the material may be challenging to occur. Observations under the three conditions using 
distilled water as a dispersion medium do not indicate significant aggregation, as the hydrodynamic radius values obtained are similar 
to the largest size of the α-Ag2WO4 NPs. The PDI results obtained were similar, indicating uniform polydispersity.
α-Ag2WO4 can release Ag + ions and W6+ ions, with Ag+ ions exhibiting high toxicity to both eukaryotic and bacterial cells. In this 
study, the concentrations of released Ag + ions were considerably higher than those required to inhibit the growth of S. aureus, E. coli, 
and C. albicans [42]. With regard to the cytotoxic effects on L929 cells, Souter et al. [43] found that Ag+ ions at a concentration of 
16.78 ppm caused a 50 % reduction in L929 cells. In our studies, the toxic concentration of the NPs (15.62 μg/mL) induced the release 
of Ag+ ions (1.82 ppm) much lower than 16.78 ppm. Thus, our data suggest that the antimicrobial activity and cytotoxicity are not 
directly related to the release of Ag+ ions. However, only a few studies have reported the toxic effects of W6+ ions.
The antimicrobial tests revealed the capability of α-Ag2WO4 NPs to inhibit the growth of C. albicans, S. aureus, and E. coli in 
suspension, findings supported by the acquired CLSM images. Different MIC and MBC/MFC values were observed for the inactivation 
of these three microorganisms. Lower concentrations of NPs inactivated E. coli and C. albicans. However, higher concentrations were 
required to inactivate S. aureus. This difference in bacterial susceptibility might be linked to the distinct chemical compositions of their 
cell walls [44]. S. aureus, a Gram-positive bacterium, possesses a thick layer of peptidoglycan on the plasma membrane; therefore, if 
Fig. 4. Intracellular ROS detection. Mean values of fluorescence intensity of A) C. albicans, B) S. aureus, and C) E. coli cells using the fluorescent 
probe CM-H2DCFDA after contact with the NPs (1.95 μg/mL for C. albicans, 31.25 μg/mL for S. aureus, and 0.24 μg/mL for E. coli) and H2O2. The 
asterisks represent the statistical difference between the groups and the positive control (PC). One-way analysis of variance with Tukey’s post hoc 
test. **pemission in all 
three microorganisms. This finding indicates that ROS formation occurs in microorganisms after exposure to α-Ag2WO4 NPs.
ROS formation can also damage host cells. These free radicals can lead to oxidative modifications of proteins, lipid peroxidation, 
DNA strand breakage, and modulation of gene expression and inflammatory response, leading to mutations or cell death [47]. 
Therefore, evaluating the biocompatibility of these nanomaterials is essential to determine the biomedical application of α-Ag2WO4 
NPs. The present study showed that the cytotoxicity of α-Ag2WO4 NPs is concentration dependent. At an NP concentration of 15.62 
Fig. 5. Biocompatibility after contact with NPs. A: Mean values of cell viability (%) of L929 cells exposed to different concentrations of NPs. The 
asterisks represent the statistical difference between the groups and the positive control (PC). One-way analysis of variance with Tukey’s post hoc 
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	Antimicrobial activity and biocompatibility of alpha-silver tungstate nanoparticles
	1 Introduction
	2 Materials and methods
	2.1 Synthesis and characterization of α-Ag2WO4 NPs
	2.2 Antimicrobial activity
	2.2.1 Confocal laser scanning fluorescence microscopy (CLSM)
	2.2.2 Intracellular ROS quantification
	2.3 Cell viability assay
	2.3.1 CLSM
	2.4 Statistical analysis
	3 Results
	3.1 Physicochemical assessment
	3.2 Ionic liberation, zeta potential, and particle size
	3.3 Antimicrobial activity
	3.4 CLSM
	3.5 Intracellular ROS detection
	3.6 MTT assay
	3.7 CLSM
	4 Discussion
	5 Conclusions
	CRediT authorship contribution statement
	Funding
	Declaration of competing interest
	Appendix A Supplementary data
	References