In March 2015, a Chinese inventor filed a patent proposing an unusual expansion of chlorine dioxide’s established role as a disinfectant. Rather than limiting its use to water treatment, environmental sanitation, or external applications, the invention proposed pharmaceutical formulations intended for administration inside the human body. The patent described three possible routes: oral administration, respiratory aerosol inhalation, and intravenous injection.
Its inventor, Zhou Weiwen (周伟文), presented the invention as the result of more than a decade of work involving chlorine dioxide production, purification, and storage. The document also included personal experimentation, observations involving two volunteers with Helicobacter pylori infection, and references to earlier animal and human investigations.
Published as CN104666330A in June 2015 and subsequently granted as CN104666330B in March 2018, the invention provides an unusual historical record of efforts to investigate chlorine dioxide as a pharmaceutical substance.
A review of the original Chinese-language patent reveals both the breadth of the inventor’s ambitions and important distinctions between his experimental observations, cited research, and proposed medical applications.
The Patent and Its Inventor
The principal document is: CN104666330B: Application of Pure Chlorine Dioxide Solution in Preparing an Internal Disinfectant The original Chinese title is 纯二氧化氯溶液制备内用消毒剂的应用. The patent identifies Zhou Weiwen as inventor. The assignee is Shenzhen City Tong Forest Science and Technology Co., Ltd.
Its recorded history includes:
| Event | Date |
| Chinese priority and filing | March 17, 2015 |
| Application publication, CN104666330A | June 3, 2015 |
| Patent grant, CN104666330B | March 16, 2018 |
| Anticipated expiration | March 17, 2035 |
The patent database lists the grant as active, although legal-status information should be verified against official Chinese patent records before drawing conclusions about enforceability.
The timing is noteworthy. This invention predates the COVID-19 pandemic by approximately five years. Its medical proposals were not developed in response to SARS-CoV-2. Instead, the inventor’s stated interests included bacterial infections, respiratory diseases, and several viral illnesses already recognized before 2015.
The Inventor’s Earlier Work
Zhou’s patent contains an autobiographical account of his work with chlorine dioxide. According to the specification, he designed a pure chlorine dioxide generator in 2001, associated with Chinese utility-model patent ZL01205297.3.
He describes spending approximately six months investigating the instability of chlorine dioxide solutions and developing a method intended to improve their storage characteristics. The account states that a company under his control pursued commercial production but abandoned the project in November 2003 because of financial losses and the expense of packaging, storage, and transportation.
More than a decade later, in April 2014, Zhou resumed preparing chlorine dioxide solutions, this time with an interest in possible pharmaceutical applications. This history is important because it identifies a technological problem that occupied the inventor before he proposed internal administration.
His initial challenge was not a particular disease. It was the preparation and preservation of chlorine dioxide solutions. The later pharmaceutical patent grew out of that chemical engineering work.
Why the Patent Emphasized Purity
One of the patent’s central distinctions concerns what the inventor called pure chlorine dioxide solution. Chlorine dioxide can be generated through different chemical processes. Depending on the preparation method, a solution may contain chlorine dioxide alongside chlorite, chlorate, residual reagents, or other reaction products. Zhou argued that the composition of a preparation was important when investigating its biological effects.
The patent therefore describes a manufacturing approach intended to produce chlorine dioxide solutions with relatively few accompanying chemical species. It specifies a claimed chlorine dioxide purity exceeding 99.5%, excluding carbon dioxide and carbonate from the impurity calculation.
The inventor also proposed separate pharmaceutical and injection-grade classifications.
The underlying research question was whether a preparation containing predominantly chlorine dioxide would behave differently from mixtures containing other chlorine oxycompounds.
That is a legitimate analytical distinction. However, chemical purity alone cannot establish that a compound is suitable for internal administration.
A pharmaceutical preparation also requires evidence concerning its behavior in biological fluids, interactions with living tissues, dose-dependent effects, and clinical outcomes.
The patent’s emphasis on purity identifies the inventor’s formulation hypothesis, not proof of medical suitability.
Three Proposed Routes of Administration
The patent contains five claims.
Its first claim establishes the broad concept of using the proposed internal disinfectant as a medicine through oral, respiratory aerosol, or intravenous administration.
The remaining claims describe the intended composition and proposed applications.
Oral Administration
The oral claims concern diseases the inventor associated with pathogenic microorganisms.
Examples include bad breath and gastric conditions involving Helicobacter pylori.
The patent proposes that chlorine dioxide’s antimicrobial properties might be relevant to organisms present in the gastrointestinal system. This application raises a biological question distinct from disinfecting drinking water.
- When chlorine dioxide is used to disinfect water, its principal function is to react with contaminants before the water is consumed.
- When a chemically reactive substance is swallowed as a proposed medication, it encounters saliva, mucus, food, stomach contents, and living tissues.
Those interactions can consume or alter the compound before it reaches any intended microbial target.
Consequently, antimicrobial activity demonstrated in water cannot automatically establish an equivalent effect within the gastrointestinal tract.
Respiratory Aerosol Administration
The patent also proposes aerosolized administration for respiratory conditions. Its list of intended applications includes rhinitis, throat inflammation, pneumonia, pneumoconiosis, and pulmonary tuberculosis.
The inventor additionally suggested that respiratory exposure might help address accumulated dust or smoke-related material in the lungs.
These proposals involve different biological problems. Infectious pneumonia and pulmonary tuberculosis involve microorganisms, while pneumoconiosis is associated with inhaled mineral dust and resulting tissue injury. A single antimicrobial mechanism would not necessarily address all of them.
The patent’s respiratory claims therefore describe a broad set of proposed applications rather than one experimentally established treatment mechanism.
Intravenous Administration
The most expansive claims involve intravenous administration. The inventor proposed applications involving several serious viral illnesses, including HIV, hepatitis viruses, and Ebola virus. The patent also refers to certain forms of leukemia.
These claims represent the greatest departure from chlorine dioxide’s established disinfectant applications. An intravenously administered substance enters a biological environment containing blood cells, proteins, antioxidants, and numerous chemically reactive molecules.
Demonstrating selective activity against a pathogen in that environment requires substantially different evidence from demonstrating microbial inactivation in water or a laboratory vessel.
The patent describes the proposed application but does not present controlled human clinical trials establishing the claimed intravenous treatments.
The Inventor’s Self-Experimentation
One of the most revealing passages in the original Chinese specification concerns Zhou’s personal experiments. He reports consuming chlorine dioxide solutions during two periods of repeated self-administration. He also describes five days of experimentation involving respiratory aerosol exposure.
These accounts are presented as part of his reasoning for pursuing pharmaceutical applications. They are historically significant because they show that the invention was influenced by the inventor’s own observations rather than arising exclusively from theoretical chemical reasoning.
However, the patent does not provide a complete clinical record of these experiences. It does not establish standardized baseline measurements, independent medical assessments, a control group, or systematic follow-up sufficient to evaluate possible adverse effects or therapeutic outcomes.
The observations therefore document the inventor’s reported experience, not a validated human safety or efficacy study. They also cannot establish that similar exposure would have the same consequences for other individuals.
The Two Helicobacter pylori Cases
The patent describes an additional observation involving two volunteers reportedly affected by Helicobacter pylori-associated gastric disease. According to Zhou, these individuals experienced improvement following the proposed chlorine dioxide intervention.
The inventor interpreted these experiences as encouragement to continue investigating pharmaceutical applications. The significance of the cases depends on information not adequately established in the patent.
For example, a clinical evaluation of H. pylori eradication ordinarily requires reliable diagnostic testing before treatment and appropriate confirmation afterward. It is also necessary to distinguish eradication of the organism from improvement in gastrointestinal symptoms.
The patent does not provide a sufficiently detailed clinical report to independently establish those outcomes.
There is no randomized comparison group, and the small number of participants prevents meaningful conclusions about general effectiveness.
Nevertheless, the cases help explain why the inventor included gastrointestinal applications among the patent claims. They are best understood as reported preliminary observations that contributed to the invention’s development.

Animal and Human Research Cited in the Patent
The patent also refers to earlier experimental work concerning chlorine dioxide exposure. Its discussion includes animal toxicity experiments and reports involving human volunteers who consumed chlorine dioxide-containing water under monitored research conditions.
These references are important, but their relationship to the patent’s proposed medical applications requires careful interpretation.
Studies involving exposure to chlorine dioxide in drinking water generally investigate toxicology, tolerability, or the consequences of water-treatment chemicals. They do not necessarily investigate whether chlorine dioxide treats an established infection.
The patent also summarizes animal experiments involving acute exposure and irritation. However, those summaries do not consistently provide the complete original study documentation needed to evaluate experimental quality.
Several claims about toxicity are expressed in unusually broad terms. The inventor’s conclusions should therefore be distinguished from the narrower findings that individual experiments may actually support.
A toxicological observation made under one set of conditions cannot establish general safety across oral, inhaled, and intravenous administration.
The Central Scientific Question: Selectivity
The patent rests on a fundamental hypothesis. Chlorine dioxide is capable of oxidizing biological molecules and inactivating certain microorganisms under appropriate conditions.
Could that chemical reactivity be directed against disease-causing organisms inside the body?
The challenge is selectivity. Chlorine dioxide does not identify microorganisms through the highly specific recognition mechanisms used by the immune system. Instead, it reacts chemically with susceptible molecules.
Those molecules may be present in pathogens, but they can also occur in normal human tissues and biological fluids.
The relevant research question is therefore not simply whether chlorine dioxide can inactivate microorganisms. That property was already well established before the 2015 patent.
The more difficult question is whether a particular formulation can reach an intended biological target, produce a measurable beneficial effect, and avoid unacceptable injury to surrounding tissues.
The patent proposes that purity and controlled formulation might help address this problem. It does not demonstrate that these requirements were satisfied for the range of diseases claimed.
What the Patent Establishes
The original document supports several historical conclusions.
First, Zhou Weiwen was investigating purified chlorine dioxide solutions before the COVID-19 pandemic.
Second, the inventor connected pharmaceutical applications to earlier work on chlorine dioxide generation and storage.
Third, the patent explicitly proposed oral, respiratory aerosol, and intravenous administration.
Fourth, the specification contains reports of self-experimentation and observations involving two volunteers with H. pylori-associated illness.
Fifth, the inventor drew upon existing antimicrobial and toxicological literature to support his reasoning.
Sixth, the Chinese patent office granted the invention in March 2018.
These facts establish a documented history of inventive activity. They do not establish that the proposed treatments were clinically effective.
A granted patent is evidence that an invention proceeded through a patent examination process. It is not a substitute for pharmaceutical approval or independently verified clinical research.
A Second Invention by the Same Researcher
The patent record reveals an important continuation. On April 15, 2015, less than one month after the original filing, Zhou Weiwen submitted another Chinese application. It was subsequently published on November 23, 2016: CN106138093A: A Method for Clearing Pulmonary Dust and Assisting Treatment of Pulmonary Infection
The application focused more specifically on respiratory conditions. Its proposed applications included pulmonary dust accumulation and infectious diseases affecting the lungs.
The document discusses aerosol delivery and the inventor’s belief that chlorine dioxide could have antimicrobial effects within the respiratory system. This is an important distinction in the patent history.
The second application is not an independent researcher’s confirmation of the first invention. Both identify Zhou Weiwen as inventor.
Instead, it demonstrates that he pursued a more specialized respiratory application alongside the broader internal-disinfection concept.
The original patent established a general pharmaceutical proposal. The later application developed one aspect of that proposal into a separate invention.
The patent database lists the respiratory application as pending, but that status should not be interpreted as confirmation of current enforceable rights.
Later Chinese Pharmaceutical Patent Activity
The citation history of CN104666330B reveals additional developments. A particularly interesting example is: WO2025214225A1: Pharmaceutical Chlorine Dioxide Antimicrobial Liquid Agent, Preparation Method Therefor, and Use Thereof
This international application claims priority from April 9, 2024, and was published October 16, 2025. It identifies several inventors, including Bao Lifeng, Zhu Chen, Xu Xiang, Bao Jingyi, and Ying Ying.
Unlike Zhou’s original patent, the newer invention places substantial emphasis on preparation methods, purity, storage stability, and laboratory antimicrobial testing. Its technical discussion includes experiments involving bacterial spores and Staphylococcus aureus under specified laboratory conditions.
The newer patent also discusses potential pharmaceutical applications. Its citation of the earlier Chinese invention establishes that Zhou’s work appeared in the subsequent patent record.
However, the relationship is one of documented prior-art citation, not necessarily scientific agreement.
The later inventors’ experiments must be evaluated independently. A patent citation does not establish that the cited invention’s medical claims were reproduced.
Why the 2025 Patent Is Worth Investigating
The newer application may be especially useful because it describes formulation characteristics and laboratory experiments in greater technical detail. That creates an opportunity to examine how later inventors approached some of the chemical questions raised by Zhou.
For example, researchers could compare the stated purity requirements, stability measurements, analytical methods, and biological testing models. The comparison might reveal whether the field developed improved ways of characterizing chlorine dioxide preparations. It would not, without additional clinical evidence, establish the effectiveness of internal administration.
The Difference Between Patent Development and Clinical Development
This distinction becomes increasingly important when reviewing multiple inventions. Patent development concerns whether inventors have described technical concepts and claimed protectable subject matter. Clinical development concerns whether a proposed medical intervention has demonstrated acceptable safety and efficacy through appropriate studies.
The two processes can overlap, but they are not equivalent.
A patent may contain laboratory experiments, animal observations, or reports of individual human experiences. Those disclosures can be useful starting points for research. However, a proposed intervention involving internal administration requires evidence appropriate to the route of exposure and the disease being investigated.
For the 2015 Chinese patent, the publicly reviewed record does not establish completed controlled clinical trials demonstrating effectiveness for the broad range of claimed conditions. Nor does it establish that the intravenous applications progressed to an approved pharmaceutical product.
The patent therefore documents an inventive hypothesis and its supporting narrative, rather than a verified medical treatment.

Questions for Further Investigation
Several questions remain open.
What happened to the inventor’s earlier chlorine dioxide generator? The patent identifies a utility-model number from 2001. Retrieving that document could clarify the technical origins of the later pharmaceutical proposal.
Were the two reported H. pylori cases documented elsewhere? Independent diagnostic records or a published case report would help establish what was actually observed.
Can the toxicological studies cited in the patent be traced to their original publications? That would allow a direct comparison between the experimental findings and the inventor’s interpretation.
Did Zhou publish scientific papers related to the 2015 inventions? Such publications might provide additional experimental detail not included in the patent specifications.
Did the respiratory application lead to laboratory or clinical investigations? Its separate filing suggests sustained interest in aerosol applications, but the patent record alone does not answer this question.
How does the 2025 international application compare with the original invention? Its analytical and antimicrobial experiments could offer a useful basis for studying subsequent formulation developments.
These questions provide a research agenda grounded in the documents themselves.
Conclusion
The Chinese patent CN104666330B represents a notable attempt to expand chlorine dioxide research from environmental disinfection into proposed pharmaceutical applications.
Filed in March 2015 by inventor Zhou Weiwen, the invention described purified chlorine dioxide formulations intended for oral administration, respiratory aerosol exposure, and intravenous injection.
Its supporting narrative included earlier chemical engineering work, personal experimentation, observations involving two volunteers with Helicobacter pylori-associated illness, and references to toxicological and antimicrobial research.
The patent was granted in March 2018.
A separate respiratory-focused application by the same inventor, filed one month after the original, demonstrates that the investigation continued into more specialized proposals involving pulmonary conditions.
Later Chinese pharmaceutical patent activity, including an international application published in 2025, provides additional material for examining the evolution of chlorine dioxide formulation research.
Together, these records establish a documented history of inventive activity extending beyond conventional water-treatment applications. They also illustrate why the evidence supporting an invention must be examined separately from the medical possibilities described in its claims.
The most valuable contribution of the 2015 patent may be the research questions it preserves: whether chemical purity changes biological behavior, how chlorine dioxide reacts within complex biological environments, and what kinds of experiments would be necessary to evaluate proposed internal applications.
Those questions remain distinct from the established use of chlorine dioxide as a disinfectant and require their own experimental answers.
Primary Sources and Further Reading
- Original Chinese patent application, published 2015
CN104666330A: Internal Disinfectant
Inventor: Zhou Weiwen (周伟文). Original Chinese-language publication.
- Chinese patent, granted 2018
CN104666330B: Application of Pure Chlorine Dioxide Solution in Preparing an Internal Disinfectant
Priority: March 17, 2015. Grant: March 16, 2018.
- Related respiratory invention, published 2016
CN106138093A: Method for Clearing Pulmonary Dust and Assisting Treatment of Pulmonary Infection
Inventor: Zhou Weiwen. Priority: April 15, 2015.
- Later international pharmaceutical application, published 2025
Priority: April 9, 2024. Publication: October 16, 2025.
- World Intellectual Property Organization
International patent search and original application records.
- China National Intellectual Property Administration
Official Chinese intellectual property authority.















