(Press-News.org)
Cancer remains one of the leading causes of death worldwide, and despite advancements in diagnosis and treatment, it continues to impose a significant health burden globally. Researchers have now started exploring various innovative methods, such as engineered nanomaterials (ENMs) that can enable targeted drug delivery to cancer cells. While promising, the in vivo behavior of pH-responsive ENMs, which continuously interact with body fluids once administered, remains poorly understood.
To address this research gap, a team of researchers led by Professor Yuta Nishina from the Research Institute for Interdisciplinary Science, Okayama University, Japan, in collaboration with Assistant Professor Yajuan Zou from the same institution and Professor Alberto Bianco from CNRS, University of Strasbourg, France, aimed to investigate how pH-responsive ENMs convert their properties into dynamic interactions with proteins and cells in vivo. Their findings were published online in the journal Small on June 01, 2025.
Graphene oxide—a carbon-based nanomaterial obtained from graphite—has recently gained popularity in nanotechnology due to its structural properties and its ability to accumulate in tumors through the enhanced permeability and retention effect. However, it faces limited applications because the immune system rapidly removes it from the circulation, resulting in inefficient uptake by cancer cells.
To overcome this barrier, the researchers designed a “charge-reversible” graphene material by attaching a hyperbranched polymer called amino-rich polyglycerol (hPGNH₂) to graphene oxide sheets and then adding an adimethylmaleic anhydride (DMMA) moiety to make the surface pH-responsive.
“When the material is in the neutral pH of the bloodstream, its surface remains negatively charged, avoiding detection by the immune system,” explains Prof. Nishina. “But when it enters the slightly acidic environment of a tumor, its surface becomes positively charged, helping it bind to and enter cancer cells.”
The team analyzed three versions of this graphene oxide-polyglycerol-DMMA (GOPG-DMMA) material by varying the densities of amino groups in hPGNH₂. These groups included GOPGNH115, GOPGNH60, and GOPGNH30. The difference in amine groups altered the resultant positive charge and thereby affected the attachment of the GOPG-DMMA material.
According to the results, the GOPGNH60-DMMA variant worked best, achieving the right balance of safety in the bloodstream and optimal positive charge in the acidic tumor environment. This balance allowed the material to reach and enter the tumor cells more efficiently while avoiding binding to healthy cells and blood proteins. Moreover, it led to higher accumulation of nanomaterials in tumor sites with fewer side effects, which was confirmed through mouse models.
“We observed that by adjusting the surface chemistry, we could control how nanomaterials behave inside the body,” says Dr. Zou. “The success of this precise control could open new avenues for ‘theranostics’ that integrates both cancer diagnosis and treatment.”
The study marks a milestone in targeted drug delivery and can help fine-tune such pH-responsive nanomaterials for more precision. Insights from the study may also help target drugs inside cells—especially in acidic compartments like lysosomes or endosomes—making treatments more precise and reducing harm to healthy tissue.
The study is part of a growing international collaboration. In 2025, Okayama University and CNRS launched the IRP C3M international research program, which aims to create more smart nanomaterials for healthcare. In the future, the researchers will continue pushing the limits of nanomaterials for better therapies.
“We now have a concrete guideline for improving the performance of pH-responsive nanomedicines,” said Prof. Nishina. “With this discovery, we are one step closer to the future of personalized medicine.”
About Okayama University, Japan
As one of the leading universities in Japan, Okayama University aims to create and establish a new paradigm for the sustainable development of the world. Okayama University offers a wide range of academic fields, which become the basis of the integrated graduate schools. This not only allows us to conduct the most advanced and up-to-date research, but also provides an enriching educational experience.
Website: https://www.okayama-u.ac.jp/index_e.html
About Professor Yuta Nishina from Okayama University, Japan
Dr. Yuta Nishina is a Professor and a leading researcher at the Research Institute for Interdisciplinary Science at Okayama University, Japan. He holds a PhD in Engineering from the Graduate School of Okayama University, Japan, and has expertise in multidisciplinary research, including nanocarbons, biomedicals, catalysis, and energy-related devices based on organic chemistry. He has over 210 peer-reviewed articles, 25 patents, and 14 book chapters to his credit. Currently, he is a part of the ongoing collaboration with the University of Strasbourg and CNRS to develop tunable, pH-responsive graphene-based nanocarriers for theranostics and precision drug delivery.
END
Bethesda, MD (Aug. 1, 2025) – Despite social media helping to increase awareness of irritable bowel syndrome (IBS) among the public (81% of health care providers agree) and advancements in treatment over the past decade, IBS symptoms continue to significantly impact patients' daily lives and productivity, according to a new survey released by the American Gastroenterological Association (AGA), in partnership with The Harris Poll, a Stagwell (STGW) agency.
The AGA IBS in America survey reveals compelling new insights that explore shifts in patient experiences, health care provider perceptions, and the treatment landscape for IBS from a similar study conducted in 2015. The 2024 comprehensive ...
Japanese rice fish, known as medaka, are small, easy to breed, and reproduce daily, making them widely used as model organisms around the world. Until now, medaka research has mainly occurred in labs where environmental conditions and study observations are easily controlled. Unnatural environmental settings such as these bring into question the accuracy of previous behavioral findings. Therefore, this study is important for answering the fundamental question of whether the behavior of animals observed in laboratories is the same as in their natural environments.
A ...
Chemistry and physics are combining forces at Columbia, and it’s leaving everyone frustrated—in a good way. New work, published today in Nature Physics, describes a new two-dimensional material capable of complex quantum behaviors that arise from its underlying chemistry, rather than its atomic structure.
“It’s a classic Columbia story—multiple groups in physics and chemistry came together to work on this new material, and we found exciting new results about how electrons move,” said Aravind Devarakonda, an applied physicist at Columbia Engineering.
The material, Pd5AlI2, ...
426,016. That’s how many packages of illegal medicines EU agencies confiscated during an eight-month operation in 2024. During the operation, they managed to find counterfeit medicines worth 11.1 million euros. And it’s an increasingly bigger problem. “Pharmaceutical crime is a growing threat in the EU,” Europol stated earlier this year.
Fortunately, a new weapon against pharmaceutical counterfeiting may be on the way. Researchers from the University of Copenhagen and Stanford University have shown in a new study that it is possible to distinguish seemingly identical medicines at the molecular level – both across ...
Many animals, including humans, can flexibly modulate their responsiveness to sounds according to different situations. This ability allows them to optimize the use of their limited brain resources by prioritizing the processing of critical information at any given moment.
In line with this idea, a research team at Nagoya University in Japan has demonstrated that when female fruit flies are eager to mate, dopaminergic signals can influence their sensitivity to sounds, including courtship sounds from males, which are an essential source of information for species reproduction.
"We believe that this finding is the first step toward understanding the neural mechanisms that underlie ...
Large ocean animals can be protected throughout much of their lifecycle by huge Marine Protected Areas (MPAs), new research shows.
Scientists tracked sea turtles, manta rays and seabirds – all of which travel far and wide to forage, breed and migrate – in the Chagos Archipelago MPA in the Indian Ocean.
In total, 95% of tracking locations were recorded inside the MPA’s 640,000 square kilometre area – suggesting it is large enough to protect these wandering animals.
The study – by a team including Exeter and Heriot-Watt universities and ZSL – also assessed the impact of a smaller 100,000 square kilometre MPA and found seabirds would be less well protected ...
Up to 60% of women experience some fear about giving birth, especially for the first time, but a new study shows why some women are more likely to stay calm and confident in the lead-up to childbirth.
In a global first, researchers from Robert Gordon University in Scotland and the University of South Australia (UniSA) investigated the factors that help ease childbirth fears, rather than stoke them.
They surveyed 88 pregnant women in their third trimester before attending antenatal classes in north-east ...
Link to video and sound (details below): https://spaces.hightail.com/receive/YDQA0P5cJ7
New study links 2023 Maui wildfire to spike in suicide, overdose
Deaths by suicide and drug overdose significantly increased in the aftermath of the August 2023 Maui wildfire, according to a new study published in the Journal of the American Medical Association (JAMA).
The study, led by Alex Ortega, dean of the Thompson School of Social Work and Public Health, and Keawe‘aimoku Kaholokula, chair of the Department of ...
Niigata, Japan – A group led by the Department of Cell Biology at the Kidney Research Center, Niigata University revealed that elevated activity of cdc42 is a critical initiation event leading to proteinuria, and proposed that suppression of cdc42 activity could be a promising therapy for nephrotic syndrome.
Glomerulus is a filtration unit of the kidney, and the glomerular capillary wall functions as a barrier, preventing the leak of plasma protein into urine. Proteinuria is a clinical symptom showing dysfunction of the barrier of glomerular capillary wall, and is an aggravating factor leading to kidney failure. Besides, ...
Sophia Antipolis, France: Analysis of over 36,000 people with high blood pressure has shown that taking more steps, even below the recommended daily target of 10,000 steps, and walking faster, is associated with a significant reduction in the risk of major problems of the heart and blood vessels.
The study, published today (Thursday) in the European Journal of Preventive Cardiology, found that compared to a daily step count of 2,300 steps, every extra 1,000 steps was linked to a 17% reduction in the risk of developing a major adverse cardiovascular event (MACE), up to 10,000 steps. Additional ...
