medical imaging – Lightsources.org

Optimizing gold nanoparticles for better medical imaging, drug delivery, and cancer therapy

2025/04/302025/04/30

Health care professionals use tiny particles of gold (nanoparticles) for a variety of medical applications — from diagnostic imaging to cancer treatment. Gold works well for these applications because it doesn’t cause adverse reactions inside the body, it doesn’t break down easily, and it’s easy to see on imaging tests.

Ontario researchers used the Canadian Light Source at the University of Saskatchewan to determine whether the size of gold nanoparticles affects how they interact with an amino acid called L-cysteine. L-cysteine plays a key role in many biological processes inside the human body. It can prevent gold nanoparticles from clumping together, which is important for ensuring medical treatments work properly. L-cysteine can form a strong bond with gold, which in turn enables it to more easily attach to specific targets, such as cancer cells.

Yolanda Hedberg, a professor of chemistry at Western University, says that while many different sizes of gold nanoparticles are used in medicine, little is known about how size affects their performance. “We’re trying to understand what they do in the body and where they go. It is important to know if the (gold) particle stays the same size, because each size has specific properties and you design the particle in this way, and then don’t want it to change in the human body.”

Using ultrabright synchrotron light — combined with other techniques — Hedberg and her team discovered that smaller gold nanoparticles (5 nanometer) bond more strongly with L-Cysteine than larger ones (10, 15, and 20 nm). For reference, a human hair is about 100,000 nm wide.

They also found that the smallest gold nanoparticles didn’t clump together as much when L-Cysteine was present. Clumping can negatively affect the effectiveness, stability, and safety of nanoparticles. “This shows they can maintain their size and properties in a biological environment,” says Hedberg.

Read more on CLS website

Research to support optimum care for ventilated preterm babies

2020/12/042021/02/11

A large international collaboration led by researchers from the Hudson Institute for Medical Research and Monash University has revealed that the ventilation of preterm babies to prevent lung collapse could create a risk of brain injury.

A/Prof Flora Wong, a researcher at Hudson Institute and Monash University, and consultant neonatologist at Monash Children’s Hospital, and a team of physiologists used the Imaging and Medical beamline (IMBL) at the Australian Synchrotron to acquire extremely clear and detailed images of blood vessels in large, preterm clinical models, in an investigation to determine if the pressure of lung ventilation affected blood vessels and blood flow.

Read more on the ANSTO website

Image: Micro-angiography showing micro-vessels

A little bit of the moon just landed at ANSTO

2019/08/122019/08/12

Research on lunar meteorite and moon crater analogues coincides with Science Week.

Researchers at the Australian Synchrotron are currently collaborating on a particularly rare, other-worldly sample; a lunar meteorite. “Although we do work on the moons of the outer planets, I believe this is our first sample from Earth’s moon, which could be more than four billion years old,” said Dr Helen Brand, planetary geologist and senior beamline scientist at the Australian Synchrotron.

Lunar meteorites are rocks found on Earth that were ejected from the Moon by the impact of an asteroid or another body. “These objects, which originate primarily from the moon’s crust, are extremely rare and precious. Because of their scarcity, scientists often use analogues or man-made versions of meteorites for investigations. “At the moment it is quite exciting as I have two projects relating to actual and analogue lunar objects, both of which are scheduled for the Imaging and Medical Beamline at the Synchrotron,” she said. n, which could be more than four billion years old,” said Dr Helen Brand, planetary geologist and senior beamline scientist at the Australian Synchrotron.

Discovery may improve cystic fibrosis treatment

2019/01/242019/01/28

A University of Saskatchewan medical research team has made a groundbreaking finding with potential to lead to more effective, longer-lasting and better-tolerated treatments for cystic fibrosis (CF).

“Though we’re still at an early stage for developing new treatments, this is a major discovery of considerable potential relevance to CF patients,” said Dr. Juan Ianowski (PhD), a physiologist at the USask College of Medicine and senior author of a paper on the finding published today in the online Nature Research journal Scientific Reports.
For over 20 years, doctors have treated CF patients with an inhaled concentrated salt solution called hypertonic saline to increase the volume of airway surface liquid (ASL)—a microscopically thin liquid lining that helps remove infected secretions from the clogged chest of a CF patient. The scientific consensus has been that an osmotic reaction drawing water from the blood was responsible for the beneficial increase in ASL from this saline treatment.
But by using synchrotron imaging at the Canadian Light Source (CLS), the national research facility at USask, the nine-member team has concluded that scientists have not completely understood the body’s reaction to the saline treatment.
>Read more on the Canadian Light Source website

Image: Dr. Julian Tam (MD) and Dr. Juan Ianowski (PhD) are researchers with the university’s Respiratory Research Centre.

The quest for better medical imaging at MAX IV

2018/11/102018/11/13

Advances in the world of physics often quickly lead to advances in the world of medical diagnostics. From the moment Wilhelm Röntgen discovered X-rays he was using them to look through his wife’s hand.

A lot of the physics principles at the foundation of MAX IV are also at the foundation of medical imaging technologies such as nuclear magnetic resonance imaging, x-ray computed tomography and positron emission tomography.
Positron emission spectroscopy is more commonly known as PET imaging. It’s a method used to study metabolic processes in the body as a research tool but also to diagnose disease. An important use today is in the diagnosis of metastases in cancer patients, but it can also be used to diagnose certain types of dementia.

In PET, a positron-emitting radionuclide is injected into a patient and travels around the body until it accumulates somewhere, depending on the chemical composition. For example, the fluorine-18 radionuclide when bound to deoxyglucose accumulates in metabolically active cells which is useful for finding metastases. The radionuclide is unstable and emits positrons which is the antimatter equivalent of an electron. When a positron and an electron inevitably meet, they annihilate one another, producing two pulses of gamma radiation traveling in opposite directions. By placing a detector around a patient, it is possible to measure the gamma radiation and convert the signal into something that can be more easily measured. These detectors are made up of materials known as scintillators which take high energy radiation and emit lower energy radiation that can be detected using fast photodetectors – photomultiplier tubes.