3 NANOTECHNOLOGY TRENDS IN RESEARCH ON H. PYLORI CONTROL

Helicobacter pylori (H. pylori) is one of the most common bacterial infections in humans and can persist for long periods in the gastric environment. A meta-analysis published in The Lancet Gastroenterology & Hepatology estimated the global prevalence of H. pylori infection at approximately 43.1% between 2011 and 2022, although prevalence varies considerably across regions and population groups.

H. pylori is associated with chronic gastritis, peptic ulcer disease, and certain malignant gastric conditions. The International Agency for Research on Cancer (IARC) classifies H. pylori as a carcinogenic agent to humans. Its strongest associations are with non-cardia gastric cancer and gastric mucosa-associated lymphoid tissue (MALT) lymphoma. Source

However, controlling H. pylori is not simply a matter of identifying an active compound capable of killing the bacterium. A drug must also remain stable in the gastric environment, penetrate the mucus layer, reach the sites where H. pylori resides, and overcome mechanisms that enable the bacterium to persist, such as biofilm formation.

This is one reason why nanotechnology has increasingly been investigated in recent years as a drug delivery platform designed to address these barriers.

Why Is H. pylori a Difficult Target to Reach?

The stomach is an exceptionally harsh environment for both bacteria and drugs.

H. pylori possesses several highly effective adaptive mechanisms. Its helical shape and flagella enable it to move through the mucus layer. Meanwhile, the enzyme urease breaks down urea to produce ammonia and carbon dioxide, helping to increase the pH in the bacterium's immediate microenvironment and enabling it to survive under acidic conditions. Adhesion proteins such as BabA also help the bacterium maintain its attachment to the gastric mucosa.

H. pylori can survive in the harsh environment of the stomach.

On the drug delivery side, at least three major barriers must be overcome.

First, gastric acidity and digestive enzymes. These may affect the stability of certain active compounds.

Second, the gastric mucus layer. H. pylori does not simply float freely in the stomach lumen; it often resides deep within the mucus layer, close to the epithelial surface. Although this mucus protects the gastric lining, it can also limit drug diffusion to the sites where the bacteria are located.

Third, biofilms. A biofilm is a community of bacteria embedded within an extracellular matrix. It can form an additional physical barrier that restricts drug penetration and contributes to the bacterium's increased tolerance to antimicrobial agents. Source

These three challenges are shaping many current approaches to developing nano-based systems for H. pylori.

Nanotechnology is increasingly being investigated for its potential to control H. pylori.

1. Nanotechnology for Protecting and Delivering Active Compounds in the Gastric Environment

One of the most fundamental research directions is the use of nanocarriers to deliver active compounds.

Rather than allowing drug molecules to be directly exposed to the gastric environment immediately after administration, active compounds can be incorporated into nanostructures designed to:

• Protect active compounds against acidic conditions and enzymes.
• Improve the dispersion of poorly water-soluble compounds.
• Control the release of active ingredients.
• Prolong gastric residence time.
• Improve access to the mucus layer and the sites where H. pylori resides.

One extensively investigated system is the nanoemulsion, a dispersion consisting of nanoscale droplets that can often carry active compounds with low water solubility.

A review published in Drug Delivery and Translational Research in 2025 and included in a 2026 issue indicates that nanoemulsions are being investigated for H. pylori applications because of their potential mucoadhesive properties, targeted delivery capabilities, controlled-release characteristics, and ability to co-deliver multiple active compounds. Source

An important point is that current research does not simply aim to make nanoparticles as small as possible. The surface properties of a nanocarrier can be engineered to alter how it interacts with mucus.

For example, positively charged chitosan can interact with negatively charged components of the mucus layer. Consequently, some chitosan-containing systems are being investigated to enhance mucosal adhesion and prolong the residence time of active compounds in the stomach. Source

Conversely, for systems intended to penetrate the mucus layer, researchers may engineer the surface to reduce interactions with mucin.

Thus, although both approaches use nanotechnology, their carrier designs can differ substantially depending on the intended objective: adhering to the mucus layer, penetrating it, or releasing active compounds at a specific site.

2. Co-Delivery of Curcumin and Antibiotics: From a Single Active Compound to a Multifunctional System

Another notable research trend is co-delivery, which involves transporting multiple active compounds within the same nanocarrier. This approach differs from simply reducing the particle size of a single substance.

A nanocarrier can be designed to deliver two or more components to the same site, such as an antibiotic combined with another biologically active compound. The research objective is to achieve complementary mechanisms of action rather than simply increasing the amount of a single drug.

A notable example was published in 2023 in World Journal of Microbiology and Biotechnology. Researchers developed a Curcumin–Clarithromycin Nanoemulsion (Cur-CLR-NE) containing both curcumin and clarithromycin. The system had an average particle size of approximately 48 nm.

In the experiments, the nanoemulsion was designed to protect both active compounds under acidic conditions and improve their activity against H. pylori.

The results showed that Cur-CLR-NE inhibited H. pylori and its biofilm more effectively than free curcumin or clarithromycin in the research models. In an animal model, the nanoformulation also achieved a greater reduction in H. pylori levels than the individual active compounds under the same dosing regimens used in the study.

Curcumin–Clarithromycin Nanoemulsion system.

Another interesting finding was that, at pH 1.5, more than 90% of the curcumin and clarithromycin remained retained within the nanoemulsion under the study's experimental conditions. This suggests that the carrier system may help protect active compounds from the acidic environment.

The broader significance of this research is that the same principle could potentially be investigated with other combinations, such as antibiotics plus urease inhibitors, antibiotics plus antibiofilm agents, or active compounds combined with gastric mucosal protective agents.

3. Nanotechnology Targeting Biofilms and Virulence Factors of H. pylori

A notable shift in H. pylori research is that the central question is no longer simply, “How can the bacterium be killed?” Researchers are also asking, “How can the mechanisms that enable the bacterium to survive be disrupted?”

Biofilms have attracted considerable attention in this regard. They act like a protective shield for bacteria against the gastric environment. Within a biofilm, bacterial cells are embedded in an extracellular matrix composed of polysaccharides, proteins, and nucleic acids.

This structure can reduce drug access to bacterial cells and allow certain H. pylori populations to persist for longer periods. Accordingly, reviews of nanomedicine for H. pylori identify mucus penetration and biofilm disruption as important approaches to improving drug delivery to the target.

Beyond biofilms, scientists are also investigating factors that help H. pylori adhere, survive, and cause disease, including BabA, HopQ, and urease.

In 2024, a study published in the journal Helicobacter evaluated several curcumin formulations in combination with azithromycin.

Among the formulations investigated, curcumin nanoemulsion demonstrated notable activity against biofilms. When combined with azithromycin, it also showed a synergistic effect in the study's experiments. Source

Notably, following treatment with curcumin nanoemulsion, the expression of several genes associated with biofilm formation and H. pylori pathogenicity—including babA, hopQ, and ureA—decreased in the research model. Source

These factors have different roles:

• BabA is associated with the ability of H. pylori to adhere to gastric epithelial cells.
• HopQ is an outer membrane protein involved in interactions between H. pylori and host cells.
• UreA is associated with the urease system, one of the key mechanisms that help the bacterium adapt to acidic conditions.

These findings point toward a broader approach: nanocarriers do not necessarily need to focus solely on delivering higher drug concentrations to bacteria. They can also be designed to interfere with biofilms, bacterial adhesion, virulence, or the adaptive mechanisms of H. pylori.

How Is Nanotechnology Changing Research on H. pylori?

Taken together, these developments reveal a clear shift in research priorities.

Previously, the central question was often: “Which active compound can inhibit H. pylori?”

Today, researchers are also asking:

• How can active compounds be protected as they pass through the gastric environment?
• How can active compounds be retained at the gastric mucosa for a sufficient period?
• How can drugs penetrate the mucus layer?
• Can multiple active compounds be delivered to the same site?
• Can a system simultaneously target the bacterium, its biofilm, and its virulence factors?

This is one of the key contributions of nanotechnology to drug delivery: it does not necessarily require the development of a new active compound. Instead, it can change how an existing compound is protected, transported, released, and delivered to its intended target.

The Future of Nanotechnology in H. pylori Research

Current evidence suggests that the most promising direction may not be the development of a “miracle nanoparticle,” but rather the ability to design a delivery system suited to a specific objective.

One system may need to protect a drug against gastric acid. Another may need to adhere to the gastric mucosa. A different system may need to penetrate mucus or biofilms. More sophisticated platforms may be able to co-deliver multiple active compounds and release them in a controlled manner at the sites where H. pylori resides.

Consequently, research into nano-based drug delivery is increasingly shifting from the question, “Has the active compound been nano-formulated?” to a more important one: “How should the nanocarrier be designed to deliver the right active compound to the right location and enable it to perform its intended function?”

This may represent one of the most significant shifts in nanotechnology research for H. pylori control today.