Particle deposition, clearance and interaction with lung surfactant

Breathing Life into Research: How Computers Help Us See Where Particles Go in the Lungs

Our lungs are incredibly complex — a delicate network of branching airways that delivers life-giving oxygen to every cell in the body. But along with oxygen, we also breathe in countless particles every day — from helpful medicines delivered through inhalers to harmful pollutants like dust, smoke, and even microplastics. Understanding exactly where these particles travel and where they end up in the lungs is essential for protecting health and improving treatments.

Dr. Suvash C. Saha’s research brings cutting-edge computer technology into this challenge. Using detailed 3D models of the lungs reconstructed from CT scans, he and his team run Computational Fluid Dynamics (CFD) simulations — advanced computer calculations that can predict how air moves and how particles behave as we breathe. These models are not generic; they are based on actual lung scans, meaning they capture the unique shapes, twists, and turns of each airway.

By simulating different breathing patterns, particle sizes, and airflow rates, the research can pinpoint “hotspots” where particles are most likely to settle. This is vital for two reasons. First, for medicine delivery, it helps improve inhalers so drugs reach exactly the parts of the lungs where they are needed. Second, for environmental health, it reveals how harmful particles from pollution or microplastics accumulate in sensitive lung regions, potentially leading to disease.

This virtual approach offers a safe, ethical, and cost-effective way to study the lungs without invasive procedures. It also opens the door to personalised healthcare — tailoring inhaler designs or treatment strategies to match a patient’s unique lung shape and breathing style.

Dr. Saha’s work doesn’t just stay in the lab. Its findings help doctors, engineers, and policymakers make informed decisions, whether that’s designing cleaner cities, developing better medical devices, or assessing the risks of emerging pollutants. By combining medical imaging with powerful computer simulations, this research provides a clear view of an invisible process, helping us all breathe a little easier.

Clearing the Airways: How Advanced Computer Models Help Us Understand Mucociliary Transport in Chronic Respiratory Diseases

Our lungs have a natural cleaning system that works quietly, day and night. Tiny hair-like structures called cilia beat in a coordinated rhythm, moving a thin layer of mucus that traps dust, bacteria, and other unwanted particles out of the airways. This process, known as mucociliary transport, is one of the body’s first lines of defence for keeping the lungs healthy and free from infection.

In people with chronic respiratory diseases such as asthma, chronic bronchitis, or chronic obstructive pulmonary disease (COPD), this cleaning system often doesn’t work as well. The mucus can become too thick or sticky, cilia can slow down, and harmful particles may linger in the lungs, leading to inflammation, infections, and breathing difficulties. Understanding exactly how and why this process changes in disease is key to developing better treatments.

Dr. Suvash C. Saha’s research uses advanced numerical methods — powerful computer-based simulations — to explore mucociliary transport in unprecedented detail. By creating 3D, physics-based models of the airways and incorporating realistic biological data, these simulations can mimic how mucus and cilia interact under healthy and diseased conditions. The models can test “what-if” scenarios — for example, how changes in mucus viscosity, cilia beat frequency, or airflow patterns might help or hinder the clearance of particles.

This approach allows researchers to explore situations that would be difficult or even impossible to study directly in patients. It provides a safe and cost-effective way to predict how different therapies — such as inhaled medicines, hydration treatments, or mechanical interventions — could improve airway clearance.

Ultimately, the goal is personalised medicine: tailoring treatments to the specific characteristics of each patient’s lungs. By combining insights from medical imaging, biological studies, and advanced computer modelling, Dr. Saha’s work aims to give doctors a clearer picture of how to restore and protect this vital self-cleaning system, helping patients with chronic respiratory diseases breathe easier and live healthier lives.

At the Molecular Frontier: How Computer Simulations Reveal the Secrets of Breathing

Every breath we take seems simple — air goes in, air comes out — yet at the microscopic level, it’s a marvel of physics, chemistry, and biology working together. One of the unsung heroes of breathing is the lung surfactant — a thin, soapy layer of molecules that coats the inside of our air sacs (alveoli). This layer dramatically reduces surface tension, stopping the tiny air sacs from collapsing and making breathing effortless.

But breathing isn’t just about air meeting lung tissue — it’s about how air and water molecules interact at this surfactant layer. These interactions are happening at nanometre scales and at speeds far too fast for the naked eye to see. Understanding this invisible process is crucial for tackling breathing difficulties in premature babies, people with acute respiratory distress syndrome (ARDS), or those exposed to pollutants that damage the surfactant.

Dr. Suvash C. Saha’s research uses molecular dynamics simulations — a powerful type of computer modelling — to zoom in on these interactions with incredible detail. Imagine a virtual microscope that doesn’t just see molecules but watches how they move, vibrate, and interact over time. By building a computer model of the lung surfactant monolayer and surrounding water and air molecules, these simulations reveal how temperature, pressure, or pollutants might change its behaviour.

Through this approach, the research can answer vital questions:

• • How does the surfactant layer adapt during inhalation and exhalation?

  • What happens when harmful particles or chemicals disrupt it?

  • How might engineered surfactants be designed to restore function when the natural system fails?

The beauty of molecular dynamics is that it allows scientists to run “what-if” scenarios in a safe, controlled virtual environment — something that would be impossible to do inside a living lung. This not only advances fundamental science but also helps in designing better medical treatments, inhalation therapies, and protective measures against airborne hazards.

By blending high-performance computing with molecular-scale biology, Dr. Saha’s work opens a new window into one of the most critical — and delicate — interfaces in the human body, bringing us closer to breathing breakthroughs that can save lives.

Tiny Threats: How Microplastics and Nanoplastics Affect Health in a Mice Model

We’ve all heard about plastic waste polluting our oceans, but the problem doesn’t end there. Over time, larger plastic items break down into tiny fragments — some small enough to see (microplastics) and others so small they’re invisible to the naked eye (nanoplastics). These particles are now found everywhere — in the air we breathe, the water we drink, and even in the food we eat. But what happens when they enter living organisms?

Dr. Suvash C. Saha’s research tackles this pressing question by studying how microplastics and nanoplastics interact inside the body, using a carefully controlled mice model. Mice are often used in biomedical research because their biological systems share many similarities with humans, allowing scientists to explore health impacts before translating findings to human medicine.

This work doesn’t just look at single types of particles — it focuses on the interactional effects. That means examining what happens when both microplastics and nanoplastics are present together. Could they amplify each other’s harmful effects? Could one type change how the other moves through the body? These are critical questions for understanding the real-world risks, because in nature, we’re rarely exposed to just one pollutant at a time.

Using advanced imaging and biochemical analysis, the research tracks where these particles go inside the body, whether they build up in certain organs, and how they influence inflammation, immune responses, and tissue health. Early findings suggest that combined exposure could pose more complex risks than either type of plastic alone, potentially affecting respiratory, digestive, and even reproductive systems.

The ultimate goal of this research is to provide scientific evidence for public health policy, guiding regulations to limit environmental plastic pollution and protect human health. It also offers a deeper understanding of how these particles might contribute to chronic diseases over time.

By uncovering how microplastics and nanoplastics interact inside a living organism, Dr. Saha’s work shines a light on a hidden threat — and brings us one step closer to solutions that keep our environment, and ourselves, healthier.