A study from FAU has shown that lipid nanoparticles restructure their membrane significantly after being absorbed into a cell and ending up in an acidic environment. Vaccines and other medicines are often packed in little fat droplets, or lipids. In this form, they are absorbed by cells and release their “cargo” once they are there. The trigger is a change in the pH value in the droplet’s surroundings. Researchers at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) have now created a computer simulation of what exactly happens. Their findings may help to optimize the release of the active substances. The results have been published in the journal Small.
Modern vaccines are often based on mRNA. mRNA is very sensitive and can be broken down easily by the body. To protect it, it is packed in little fat droplets, known as lipid nanoparticles, and injected in this form. In the body, the nanoparticles are absorbed by the cells and stored in microscopic sacs known as endosomes. The environment inside them is fairly acidic.
“In response to the rise in acidity, the lipids deposit their cargo inside the cells,” explains Prof. Dr. Rainer Böckmann, Professor of Computational Biology at the Department of Biology at FAU.
Lipid nanoparticles consist of various components. One important component is what is known as amino lipids. In other words, lipids incorporate a nitrogen atom. Amino lipids can absorb hydrogen ions in an acidic environment and become positively charged. They are absorbed at a specific pH value, which varies depending on the specific amino lipid. At this point, also referred to as the pKa value, the lipids change from not having a charge to having a charge.
“This change in their properties is what ultimately causes the nanoparticles to release their content,” explains Böckmann.
When the lipid is absorbed into the endosome, a slightly acidic setting, a chain reaction is triggered: Increasing numbers of amino lipids absorb hydrogen and become positively charged. This gradually destabilizes the nanoparticle until the cargo is delivered.
The doctoral candidate Marius Trollmann and Prof. Böckmann simulated this process on the supercomputers at the Erlangen National High-Performance Computing Center (NHR@FAU). They were able to produce a film showing how the lipid’s membrane gradually re-forms when the surrounding pH value changes.
“We were also able to demonstrate to what extent the pKa value of the amino lipids depends on the surrounding molecules,” explains Böckmann. “Depending on which other compounds are available in their surroundings, it can undergo a shift of up to four units.”
When they are in a watery environment with a pH value of nine, the amino lipids absorb hydrogen ions and become positively charged. The lipid environment surrounding the nanoparticle shifts the transition point to a pH value of five to six, in other words the value that is found within the endosomes.
Findings significant for research into vaccines
The study shows for the first time in detail how acidification in the endosome causes the lipid nanoparticles to release their content. The researchers simulated a lipid droplet with a molecular composition that is already used in practice: Nanoparticles such as these are used as transport vehicles for mRNA vaccines, not only in the fight against COVID, but potentially in future also for treating cancer.
“In order for that to be successful, it is important that the nanoparticles release as large a quantity of their mRNA into the cell as possible,” stresses Böckmann. “Using our simulation, it is possible to continue to optimize the composition of the nanoparticles to make the process even more effective in future.”
Publication details
Marius F.W. Trollmann et al, Decoding pH‐Driven Phase Transition of Lipid Nanoparticles, Small (2026). DOI: 10.1002/smll.202511381
Journal information: Small
Key concepts
Biomolecular & subcellular processesNanostructuresSubcellular structuresSurfactants, micelles & vesiclesMolecular dynamics
Provided by Friedrich–Alexander University Erlangen–Nurnberg
News
Scientists Discover the Brain May Enter a New Biological Phase Between 50 and 75
A single-cell study reveals major changes in immune cells, genome organization, and gene regulation within the aging human hippocampus, offering important insights into brain aging and dementias associated with age. Between roughly ages 50 [...]
Our books now available worldwide!
Online Sellers other than Amazon, Routledge, and IOPP Indigo Global Health Care Equivalency in the Age of Nanotechnology, Nanomedicine and Artifcial Intelligence Global Health Care Equivalency In The Age Of Nanotechnology, Nanomedicine And Artificial [...]
Unzipping the Code of Life: Scientists Pinpoint Where DNA First Opens
Researchers mapped where DNA first opens and how a helicase gate may release one strand as genome copying begins. Before a cell can divide, it must open its tightly wound DNA and begin copying the entire [...]
Scientists Tested an 8-Hour Eating Window and Found a Surprising Brain Benefit
Limiting the daily eating window may provide brain benefits beyond those associated with weight loss. Eating within a shorter daily window may provide cognitive benefits beyond those associated with weight loss alone, according to [...]
Focused Ultrasound Opens Blood-Brain Barrier to Treat Brain Cancer
Summary: A new study demonstrates that primary brain tumors (gliomas) are particularly receptive to targeted drug delivery using focused ultrasound (FUS) combined with microbubbles. The team developed a high-resolution MRI protocol to track blood-brain barrier [...]
AI’s promise and practical limits in drug discovery
AI tools are becoming increasingly common in early drug discovery, allowing scientists to analyse data and navigate large volumes of research. However, according to Dr Raminderpal Singh, turning that potential into consistent scientific workflows [...]
GHCE Concept
From the preface of the book Global Health Care Equivalency in the Age of Nanotechnology, Nanomedicine and Artificial Intelligence, Edited by Frank Boehm: Since the publication of my first book (Nanomedical Device and Systems [...]
Healthcare Headlines: Challenges and Advances in 2026
Health-related updates reveal financial adjustments by Universal Health Services due to Medicaid reimbursement uncertainties, significant pollution-linked health concerns from French-British oil firm Perenco in Congo, drug trial setbacks, potential restructuring at major medical firms, [...]
Scientists Discover the Brain Protein That Helps Alzheimer’s Spread Through the Brain
Scientists have identified a brain protein that may help Alzheimer’s spread, revealing a potential new target for slowing the disease’s progression. Alzheimer’s disease is closely linked to the accumulation of a toxic form of the protein [...]
How Immune Dysregulation Contributes to Psychiatric Disorders
Introduction Growing evidence suggests that disruptions in immune function may play an important role in the development and progression of psychiatric disorders. However, immune mechanisms probably contribute more strongly in some patients than others, [...]
Electrostatic Discharge Boosts Triboelectric Nanogenerator Current and Enables DC Output
Controlled electrical discharges could enable triboelectric nanogenerators to achieve higher peak currents, extending nano-enabled energy harvesting into chemical processing and self-powered sensing. Paper: Electrostatic discharge as a breakthrough strategy for triboelectric nanogenerators. A new review [...]
Swiss laboratory uses old drugs against rare diseases
Researchers at the University of Geneva are combing through collections of approved drugs to find new therapies for rare diseases – with some success. This approach is gaining traction around the world, while pharmaceutical [...]
Nanozyme Aptasensors Show Promise for Faster Food, Health, and Environmental Testing
By pairing robust artificial enzymes with highly selective aptamers, nanozyme aptasensors could help detect disease biomarkers, pathogens, and contaminants faster, but the review shows that real-world deployment still depends on overcoming matrix interference, biofouling, [...]
Paralyzed Man Feels Sensation Again With Brain Stimulation Device
Aneuroprosthetic system has allowed a man with paralysis to grasp and lift objects and feel touch again. The device helped 42-year-old Keith Thomas of Massapequa, New York, who was paralyzed from the chest down [...]
Global Cancer Cases Could Surge 67% by 2050, New Report Warns
New data reveal major geographic disparities and highlight the urgent need for global action on prevention, early detection, and equitable access to treatment. For roughly one in five people worldwide, cancer will become part [...]
A Deadly Ebola-Like Virus Is Spreading. Are We Ready?
BU virologist Nancy Sullivan says the Bundibugyo outbreak in the Democratic Republic of the Congo underscores the need for broader outbreak preparedness. The death of a nurse marked the moment health officials recognized that [...]
