WO₃ Nanoparticles: 6 Critical Safety Questions That Could Shape the Future of CT Imaging and Nanomedicine
Why WO₃ Nanoparticles Matter for the Future of CT Imaging
Medical imaging is entering an era in which diagnostic performance, biological compatibility, and treatment potential must be evaluated together. Advances in computed tomography (CT), Medical AI, and nanomedicine are creating new opportunities to improve how diseases are detected, characterized, and monitored. Yet every promising material must answer a fundamental question before it can move toward clinical use: Can it deliver useful diagnostic performance without introducing unacceptable biological risks?
Tungsten trioxide (WO₃) nanoparticles are attracting scientific interest because tungsten has a high atomic number and can provide substantial X-ray attenuation under appropriate imaging conditions. Researchers have investigated tungsten-based nanomaterials for CT contrast enhancement and other biomedical applications. However, high X-ray attenuation alone does not establish that a material is a safe, effective, or economically viable clinical contrast agent.
A 2019 study published in the Journal of Nanomaterials, titled “Highly Crystalline WO₃ Nanoparticles Are Nontoxic to Stem Cells and Cancer Cells,” investigated the preparation, dispersion characteristics, and in vitro cytotoxicity of highly crystalline WO₃ nanoparticles. The researchers evaluated dental pulp stem cells (DPS) and MCF-7 human breast cancer cells, comparing formulations with and without dextran stabilization.
The findings offer useful evidence about cellular responses under specific experimental conditions. They do not establish long-term safety, clinical effectiveness, or regulatory approval for human use.
This distinction matters to radiologists, biomedical engineers, healthcare AI developers, medical device companies, and researchers evaluating next-generation imaging materials. The future of nanomedicine depends not only on promising laboratory findings but also on reproducible manufacturing, comprehensive safety testing, validated imaging performance, and demonstrable clinical value.
1. Medical Imaging and WO₃ Nanoparticles: Why Tungsten Matters
1.1 Understanding X-ray attenuation in CT imaging
Computed tomography creates cross-sectional images by measuring how X-rays pass through the body. Different tissues and materials attenuate X-rays to different degrees, allowing CT systems to reconstruct anatomical structures and distinguish variations in tissue composition.
Iodine-based contrast agents are widely used in clinical CT. Tungsten, a high-atomic-number element, also has physical properties that make tungsten-containing materials interesting candidates for imaging research.
The 2019 WO₃ nanoparticle study discusses the X-ray attenuation properties of tungsten as part of the rationale for investigating the material. The paper reports mass attenuation coefficients at 100 keV of 4.438 cm²/g for tungsten and 1.94 cm²/g for iodine.
These values describe material behavior at a specified photon energy. They should not be interpreted as proof that a tungsten-based nanoparticle formulation will outperform an iodine-based contrast agent in clinical CT.
Actual imaging performance depends on several interacting factors:
X-ray energy spectrum and acquisition settings.
Concentration and distribution of the imaging material.
Particle composition and formulation.
Tissue environment and biological distribution.
Image reconstruction and noise characteristics.
Safety, clearance, and tolerability at the required dose.
Consequently, evaluating a potential CT contrast material requires both physical characterization and imaging experiments under relevant conditions.
1.2 What makes WO₃ nanoparticles scientifically interesting?
Tungsten trioxide is an inorganic compound composed of tungsten and oxygen. Its crystal structure, particle morphology, surface chemistry, and dispersion behavior can influence its physical and biological properties.
In the 2019 study, the researchers prepared highly crystalline orthorhombic WO₃ nanoparticles by thermally decomposing ammonium paratungstate in air at 600°C. The resulting powder was dispersed in water and treated with ultrasound for six hours.
The paper reports the following characteristics:
Crystal structure: orthorhombic WO₃.
X-ray diffraction-derived crystallite size: approximately 65 ± 2 nm.
Hydrodynamic radius of the non-stabilized dispersion: approximately 27 nm.
Hydrodynamic radius of the dextran-stabilized dispersion: approximately 53 nm.
Tested concentrations in cellular experiments: 0.2–200 μg/mL.
These measurements describe different properties. Crystallite size estimated from X-ray diffraction is not interchangeable with hydrodynamic size measured by dynamic light scattering (DLS).
DLS estimates the effective size of particles moving through a liquid, including the influence of surface-associated molecules, hydration layers, and aggregation. This distinction is important because a nanoparticle's behavior in a biological fluid may differ considerably from its appearance in a dry powder.
doi: 10.1155/2019/5384132
Figure 1. WO₃ Nanoparticle Morphology and Crystal Structure
The original figure presents scanning electron microscopy (SEM) and X-ray diffraction (XRD) results. SEM helps characterize morphology and particle aggregation, while XRD provides evidence about crystal structure and crystallinity.
Neither method alone provides a complete description of a biomedical nanomaterial. SEM does not establish the particle's hydrodynamic size in biological fluids, and XRD does not directly measure dispersion stability. Together with surface characterization and solution-based measurements, these techniques provide a stronger foundation for material assessment.
1.3 How Medical AI could support nanomedicine research
Medical AI and nanomedicine address different but potentially complementary challenges.
AI algorithms can help quantify imaging data, analyze relationships between experimental conditions and image quality, and identify patterns across large research datasets. In a future research workflow, these tools could support the evaluation of nanoparticle concentration, CT attenuation, image noise, and acquisition parameters.
Machine learning may also help researchers examine relationships between particle size, surface chemistry, dispersion stability, and measured biological responses.
However, these are potential research applications rather than established clinical capabilities of the specific WO₃ formulation studied in 2019.
AI does not eliminate the need for experimental validation. A model trained on limited laboratory data may fail when applied to different scanners, imaging protocols, biological environments, or nanoparticle formulations.
For Healthcare AI developers, the essential principle is straightforward: computational analysis can improve the interpretation of reliable data, but it cannot replace missing safety evidence.
2. Nanoparticle Stability: The Role of Dextran
2.1 Why dispersion stability matters
Nanoparticles can aggregate when exposed to changes in ionic strength, pH, temperature, or interactions with proteins and other biological molecules.
Aggregation can alter effective particle size, sedimentation, cellular uptake, and biological distribution. In a medical application, these changes may affect both imaging performance and safety.
The 2019 study compared WO₃ dispersions prepared with and without dextran stabilization.
Dextran is a hydrophilic polysaccharide that can be used to modify nanoparticle surfaces and influence dispersion behavior. A polymer-associated layer may help reduce direct particle-to-particle contact and improve stability under certain conditions.
Nevertheless, stabilization is formulation-dependent. A larger hydrodynamic size does not automatically mean that a nanoparticle performs worse, nor does improved dispersion automatically demonstrate biological safety.
doi: 10.1155/2019/5384132
Figure 2. Dextran Stabilization and Dispersion Characteristics of WO₃ Nanoparticles
The original figure compares sedimentation behavior, particle-size distributions, and stabilization-related characteristics of the WO₃ dispersions.
The study reports that both dispersions showed favorable sedimentation stability under the experimental conditions. After seven days of storage, the clear supernatant volume did not exceed 7%.
This observation supports the conclusion that the tested dispersions remained reasonably stable under the reported storage conditions. It does not establish long-term stability in blood, plasma, or other complex biological fluids.
For biomedical development, stability testing should include relevant biological media, storage conditions, concentration ranges, and potential interactions with proteins.
2.2 What dextran stabilization does—and does not—prove
Dextran stabilization may influence particle interactions and reduce aggregation in a particular formulation. However, its presence does not guarantee that a final product will be safe for intravenous administration.
Further evaluation would be required to investigate:
Stability in serum or plasma.
Protein adsorption and protein-corona formation.
Hemocompatibility and potential hemolysis.
Coagulation and complement activation.
Immune responses and inflammatory effects.
Biodistribution, organ accumulation, and clearance.
Batch-to-batch consistency and storage stability.
These investigations are important because the biological environment can substantially change nanoparticle behavior.
In medical device development and nanomedicine research, stability is not simply a manufacturing convenience. It is a critical variable that may affect dose consistency, imaging performance, and biological response.
3. WO₃ Nanoparticle Cytotoxicity: What the Cell Experiments Showed
3.1 MTT assay findings
The researchers exposed DPS and MCF-7 cells to WO₃ nanoparticles at concentrations of 0.2, 2, 20, and 200 μg/mL. Following 24 hours of exposure, they used the MTT assay to assess cellular metabolic activity.
The paper reports no statistically significant differences in MTT-based metabolic activity between the control and treated groups across the tested concentration range.
This finding suggests that the tested formulations did not produce a significant reduction in the measured metabolic activity under those experimental conditions.
However, an MTT assay is an indirect measure. It does not independently establish that every aspect of cellular function remains normal. Nanomaterials may also interfere with optical measurements or assay chemistry, making material-specific interference controls important.
A 24-hour experiment cannot establish long-term safety or predict the consequences of repeated exposure. Those questions require additional studies using appropriate exposure periods and independent biological endpoints.
doi: 10.1155/2019/5384132
Figure 3. MTT Assay of WO₃ Nanoparticles in DPS and MCF-7 Cells
The figure presents MTT assay results for MCF-7 breast cancer cells and dental pulp stem cells after 24 hours of exposure.
Figure 3(a): MCF-7 cells.
Figure 3(b): DPS cells.
The central finding is the absence of statistically significant differences in the measured metabolic activity under the tested conditions.
When interpreting the graphs, readers should consider the reported variability, sample size, statistical method, and experimental replication. The paper reports three to four experimental repetitions and the use of the Mann–Whitney U test, with a significance threshold of p ≤ 0.05.
A nonsignificant result does not prove that two conditions are biologically equivalent. Small effects, specific functional changes, and longer-term responses may require different study designs to detect.
3.2 LIVE/DEAD fluorescence microscopy
Cell viability assays provide complementary information. The MTT assay measures metabolic activity indirectly, whereas LIVE/DEAD assays use staining characteristics to help distinguish viable and nonviable cells.
The researchers examined DPS and MCF-7 cells exposed to stabilized and non-stabilized WO₃ formulations.
doi: 10.1155/2019/5384132
Figure 4. LIVE/DEAD Fluorescence Microscopy After WO₃ Nanoparticle Exposure
The original figure presents representative microscopy images from control groups and different nanoparticle concentrations.
The study reports no clear increase in cell death under the tested conditions and describes the observed cellular morphology as generally preserved.
Representative images are useful for visual assessment, but they cannot establish the response of an entire cell population on their own. Quantitative analysis, independent experimental replication, and additional toxicity assays are necessary for a more comprehensive assessment.
Differences between MCF-7 and DPS cells should also be interpreted carefully. These models have different biological characteristics, and direct comparisons of signal intensity do not necessarily establish that one cell type is more resistant or more sensitive to the material.
3.3 Mitochondrial membrane potential
Mitochondria play an important role in cellular energy metabolism and signaling. Changes in mitochondrial membrane potential can indicate cellular stress or alterations in mitochondrial function.
The study used JC-1 staining to evaluate mitochondrial membrane potential following WO₃ nanoparticle exposure.
doi: 10.1155/2019/5384132
Figure 5. Mitochondrial Membrane Potential Following WO₃ Exposure
The researchers observed a slight reduction in mitochondrial membrane potential as nanoparticle concentration increased.
This finding is important because cellular stress may occur without immediate or obvious cell death. A cell can remain viable while showing changes in particular metabolic or physiological processes.
The biological significance of the reported trend requires further investigation. Additional metabolic measurements, oxidative-stress assays, functional studies, and longer exposure experiments would help clarify whether the observed changes represent a meaningful adverse effect.
For nanomedicine development, the objective is not simply to avoid immediate cell death. It is to establish that the material can perform its intended function while preserving relevant biological functions.
3.4 Nuclear morphology and genotoxicity
Nuclear morphology provides another source of information about potential cellular damage.
The researchers used Hoechst 33342 staining to observe the nuclei of treated cells.
doi: 10.1155/2019/5384132
Figure 6. Nuclear Morphology of DPS and MCF-7 Cells After WO₃ Exposure
The study did not identify obvious morphological changes in the nuclei under the tested conditions.
However, normal-appearing nuclear morphology does not exclude DNA damage or other forms of genotoxicity. The paper identifies additional testing, including comet assays, as relevant to further evaluation.
The appropriate conclusion is therefore limited: the tested conditions did not produce clearly observable nuclear morphological abnormalities in the reported experiment.
4. Biological Safety: Why In Vitro Results Are Not Enough
One of the most important principles in nanomedicine is the distinction between in vitro findings and in vivo safety.
Cell cultures cannot fully reproduce the complexity of blood circulation, immune responses, organ filtration, protein-corona formation, tissue distribution, metabolism, and excretion.
Consequently, a material that shows limited cytotoxicity in cultured cells cannot automatically be considered safe for intravenous administration or repeated clinical use.
The 2019 paper discusses previous research raising concerns about the aggregation and toxicity of certain non-stabilized tungsten oxide particles. These observations reinforce the importance of formulation and dispersion characteristics in addition to chemical composition.
4.1 Phototoxicity and light-activated effects
Some tungsten oxide nanomaterials exhibit photoactive properties. Under particular irradiation conditions, certain formulations may generate reactive oxygen species or undergo photochemical reactions.
A 2018 study by Popov and colleagues investigated the photo-induced toxicity of tungsten oxide photochromic nanoparticles. Such findings indicate that the biological effects of tungsten oxide materials may depend on the specific formulation and exposure conditions.
This does not mean that every WO₃ formulation behaves identically. Differences in particle composition, surface properties, light wavelength, irradiation intensity, and exposure duration can influence the response.
Photoactivity may be relevant to selected therapeutic research applications, but it can also introduce safety concerns that require dedicated investigation.
4.2 Essential safety tests before clinical translation
A responsible development program should evaluate several categories of risk.
Material characterization: Confirm crystal structure, size distribution, surface chemistry, impurities, and aggregation behavior.
Cellular safety: Assess cytotoxicity, oxidative stress, mitochondrial function, inflammation-related endpoints, and genotoxicity.
Blood compatibility: Investigate hemolysis, coagulation, complement activation, and interactions with blood proteins.
In vivo safety: Examine biodistribution, organ accumulation, clearance, acute toxicity, and repeated-dose effects in suitable models.
Imaging performance: Measure CT attenuation, image noise, contrast-to-noise characteristics, and performance under clinically relevant acquisition conditions.
Clinical and regulatory development: Establish adequate nonclinical evidence and follow the applicable regulatory requirements before initiating appropriate clinical studies.
The results should inform each subsequent stage. For example, substantial aggregation in serum may require formulation changes or additional risk assessment before further development.
These steps are essential for demonstrating reproducibility and safety. They should not be treated as optional administrative expenses.
5. Healthcare Innovation and Hospital Costs: How Should Economic Value Be Evaluated?
The commercial potential of a new imaging material depends on more than laboratory performance.
The 2019 WO₃ nanoparticle study did not directly measure hospital cost savings, clinical outcomes, return on investment, or cost-effectiveness. Any economic benefit therefore remains a question for future evaluation rather than an established result.
5.1 Factors that influence total development and clinical costs
The total cost of a medical imaging technology includes more than the price of the contrast material itself.
Relevant factors include:
Raw materials and nanoparticle manufacturing.
Purification, characterization, and quality control.
Sterile manufacturing and storage stability.
Preclinical safety studies and clinical trials.
Imaging equipment and workflow requirements.
Staff training and image-processing resources.
Adverse-event monitoring and patient management.
Regulatory submissions and post-market surveillance.
A nanoparticle formulation with promising imaging properties may still be economically unattractive if manufacturing, safety testing, or quality-control costs are excessive.
Conversely, if future clinical evidence demonstrates improved diagnostic performance, fewer repeat examinations, or other meaningful benefits in a defined application, those outcomes could be incorporated into a formal cost-effectiveness analysis.
Such benefits must be demonstrated using appropriate data rather than assumed from laboratory results.
5.2 Calculating return on investment
Healthcare organizations and medical technology companies should compare a new workflow with an appropriate existing alternative.
A financial assessment may consider examination volume, cost per examination, repeat imaging rates, interpretation time, adverse-event costs, equipment costs, and implementation expenses.
A commonly used formula is:
ROI (%) = (Net Benefit ÷ Investment Cost) × 100
Net benefit should reflect measured financial gains after accounting for relevant additional costs over a defined period.
The WO₃ nanoparticle study does not provide the clinical or financial data needed to calculate an actual ROI. Reporting a specific return would therefore be unsupported.
5.3 Where Medical AI may contribute
Medical AI may support the analysis of image quality, examination workflows, diagnostic performance, and resource utilization. However, AI implementation does not automatically reduce costs.
Development, data governance, cybersecurity, software integration, staff training, validation, and ongoing monitoring all contribute to the total cost of an AI system.
When evaluating AI-assisted imaging and nanoparticle-based contrast technologies together, their individual effects should first be measured separately. The additional benefit of combining them should then be evaluated using appropriate clinical and economic evidence.
For hospitals, insurers, medical device companies, and AI SaaS developers, the central question is not whether a technology is innovative. It is whether it produces a measurable and reproducible benefit at an acceptable cost and risk.
6. Nanomedicine and Theranostics: Connecting Imaging With Treatment
Theranostics combines diagnostic and therapeutic approaches. In nanomedicine, researchers investigate whether a material can support imaging while also contributing to treatment or treatment-response monitoring.
Certain tungsten oxide nanostructures have been investigated for CT imaging, photothermal applications, and multimodal approaches. For example, Zhou and colleagues studied tungsten oxide nanorods for tumor CT imaging and photothermal therapy, while Wen and colleagues investigated ultrasmall WO₃−x nanodots for multimodality imaging and combined cancer therapy.
These studies provide broader scientific context, but different tungsten oxide formulations may have substantially different properties. Their findings should not be directly attributed to the orthorhombic WO₃ formulation evaluated in the 2019 cytotoxicity study.
The original study did not demonstrate clinical cancer treatment or establish a combined diagnostic-and-therapeutic application in human patients.
Future research could investigate the following questions:
How does WO₃-based CT attenuation compare with established iodine-based contrast agents under matched imaging conditions?
Does the nanoparticle formulation remain stable in plasma or other biological fluids?
Which organs accumulate the material, and how is it ultimately cleared?
How do irradiation conditions influence biological effects in normal and diseased tissues?
Can validated AI methods improve quantitative assessment of imaging performance or treatment response?
Can manufacturing processes maintain consistent particle properties at larger production scales?
Answers to these questions will help determine whether tungsten oxide nanomaterials can progress from experimental research toward clinically useful applications.
7. Summary of the Evidence
| Evaluation area | Finding reported in the 2019 study | Important limitation |
|---|---|---|
| Crystal structure | Highly crystalline orthorhombic WO₃ | Other formulations may behave differently |
| Crystallite size | Approximately 65 ± 2 nm | Not equivalent to hydrodynamic size |
| Dispersion | Stabilized and non-stabilized formulations were compared | Does not establish long-term in vivo stability |
| Cell models | DPS and MCF-7 cells | Does not represent every human tissue |
| MTT assay | No significant metabolic-activity difference at 0.2–200 μg/mL | Does not establish long-term safety |
| Mitochondrial response | A slight reduction trend was reported | Further studies are needed to establish significance |
| Nuclear morphology | No obvious morphological changes reported | Does not exclude genotoxicity |
| Clinical translation | Potential imaging material discussed | Clinical efficacy, safety, and cost-effectiveness remain unestablished |
The distinction between observed results and unresolved questions is central to responsible scientific communication. A promising laboratory finding is valuable, but its significance depends on what the experiment actually measured.
8. A Research Roadmap for Medical Imaging Applications
A structured development pathway can help researchers determine whether WO₃ nanoparticles warrant further investigation for medical imaging.
Stage 1: Establish reproducible material properties
Characterize crystal structure, particle-size distribution, surface chemistry, impurities, and dispersion stability across independent manufacturing batches.
Stage 2: Expand biological safety testing
Build on short-term cell experiments with genotoxicity, oxidative stress, blood compatibility, and longer-term exposure studies. For photoactive formulations, assess the effects of relevant irradiation conditions.
Stage 3: Validate CT imaging performance
Measure attenuation, image noise, contrast-to-noise characteristics, and performance across appropriate acquisition settings. Comparisons with established contrast agents should use controlled and clinically relevant conditions.
Stage 4: Evaluate biodistribution and regulatory requirements
Use suitable preclinical models to investigate organ accumulation, clearance, toxicity, and administration-related risks. Develop a regulatory strategy based on the intended application and applicable requirements.
Stage 5: Assess AI integration and economic value
AI-based methods may help quantify imaging performance and analyze complex datasets. Their performance must be independently validated. Economic analyses should use real data on clinical outcomes, operating costs, implementation requirements, and relevant alternatives.
This roadmap represents a proposed development framework, not evidence that the specific WO₃ formulation is ready for clinical use.
Quiz
Question 1
Which cell models were used in the 2019 WO₃ nanoparticle study?
A. Liver cells and lung epithelial cells only.
B. Dental pulp stem cells and MCF-7 breast cancer cells.
C. Blood cells from healthy adults only.
D. Neuronal and cardiac cells from animals only.
E. Human patients receiving intravenous nanoparticles.
Correct answer: B
Explanation: The researchers used dental pulp stem cells and MCF-7 breast cancer cells. These models provided information about cellular responses under the tested conditions, but they cannot represent every human tissue or establish clinical safety.
Question 2
Why was the hydrodynamic radius greater in the dextran-stabilized WO₃ dispersion?
A. Dextran removed all tungsten from the formulation.
B. Dextran completely dissolved the nanoparticles.
C. Dextran-associated surface layers contributed to the measured hydrodynamic size.
D. Larger nanoparticles are always nontoxic.
E. Surface stabilization has no relationship to dispersion behavior.
Correct answer: C
Explanation: The study reported a larger hydrodynamic radius for the dextran-stabilized formulation. A polymer-associated layer can influence the effective size measured in a liquid. However, increased size does not automatically establish either better performance or improved safety.
Question 3
What does the absence of a statistically significant difference in MTT assay results mean?
A. The nanoparticles are completely safe for every administration route.
B. Repeated long-term exposure cannot produce toxicity.
C. No statistically significant difference in measured metabolic activity was observed under the tested conditions.
D. Biodistribution and clearance have already been established.
E. Clinical superiority over iodine-based contrast agents has been demonstrated.
Correct answer: C
Explanation: MTT assay results must be interpreted within the experimental conditions, cell models, concentrations, and exposure periods used. A nonsignificant result does not establish long-term safety, clinical superiority, or the absence of every possible toxic effect.
Conclusion: What Must Happen Before WO₃ Nanoparticles Become a Medical Imaging Innovation?
WO₃ nanoparticles are scientifically interesting candidates for further investigation because of their material properties and potential relevance to X-ray imaging. Research on selected tungsten oxide nanostructures also illustrates the broader interest in combining medical imaging with therapeutic applications.
The 2019 study by Han and colleagues investigated highly crystalline orthorhombic WO₃ nanoparticles, compared dextran-stabilized and non-stabilized dispersions, and evaluated short-term cellular responses in DPS and MCF-7 cells. The authors reported no statistically significant difference in MTT-based metabolic activity across the tested concentration range and no obvious nuclear morphological abnormalities under the reported conditions.
At the same time, the observed trend in mitochondrial membrane potential and the limitations of short-term cell experiments reinforce the need for broader safety assessment.
The key contribution of this research is not proof that WO₃ nanoparticles are already clinically safe or effective. It is evidence that material structure, dispersion characteristics, and cellular responses deserve systematic investigation when evaluating candidate nanomaterials for biomedical applications.
Future development will require additional studies of biological-fluid stability, genotoxicity, biodistribution, organ accumulation, clearance, imaging performance, and manufacturing reproducibility. Clinical and economic value must be established independently rather than inferred from promising material properties.
Medical AI may eventually help researchers analyze imaging data and evaluate performance across complex experimental conditions. Nevertheless, reliable clinical translation will continue to depend on high-quality evidence, appropriate validation, and transparent reporting of limitations.
The future of nanomedicine will be shaped not simply by how innovative a material appears in the laboratory, but by whether its safety, performance, reproducibility, and clinical value can be demonstrated.
Explore More Medical Imaging and Healthcare Innovation
If you are interested in CT technology, Medical AI, biomedical nanotechnology, and next-generation diagnostic tools, explore related research with a focus on both potential benefits and unresolved safety questions.
For researchers and healthcare technology developers, a useful starting point is to compare material characterization, biological compatibility, validated imaging performance, and manufacturing requirements before drawing conclusions about clinical or commercial potential.
Medical Information Disclaimer
This article is intended for scientific education and informational purposes. It does not establish the safety, efficacy, regulatory approval, or cost-effectiveness of any specific WO₃ nanoparticle formulation. Clinical applications require appropriate preclinical and clinical evidence and compliance with applicable regulatory requirements.
References
[1] B. Han et al., “Highly Crystalline WO₃ Nanoparticles Are Nontoxic to Stem Cells and Cancer Cells,” Journal of Nanomaterials, vol. 2019, Article ID 5384132, 2019. doi: 10.1155/2019/5384132.
[2] Z. Zhou et al., “Tungsten oxide nanorods: an efficient nanoplatform for tumor CT imaging and photothermal therapy,” Scientific Reports, vol. 4, Art. no. 3653, 2014. doi: 10.1038/srep03653.
[3] L. Wen et al., “Ultrasmall Biocompatible WO₃−x Nanodots for Multi-Modality Imaging and Combined Therapy of Cancers,” Advanced Materials, vol. 28, no. 25, pp. 5072–5079, 2016. doi: 10.1002/adma.201506428.
[4] A. L. Popov et al., “Photo-induced toxicity of tungsten oxide photochromic nanoparticles,” Journal of Photochemistry and Photobiology B: Biology, vol. 178, pp. 395–403, 2018. doi: 10.1016/j.jphotobiol.2017.11.021.
[5] P. Dong et al., “WO₃-based photocatalysts: morphology control, activity enhancement and multifunctional applications,” Environmental Science: Nano, vol. 4, pp. 539–557, 2017. doi: 10.1039/C6EN00478D.
[6] H. Zheng et al., “Nanostructured tungsten oxide—properties, synthesis, and applications,” Advanced Functional Materials, vol. 21, no. 12, pp. 2175–2196, 2011. doi: 10.1002/adfm.201002477.
댓글
댓글 쓰기