Compared to their bulk materials, nanomaterials offer a wide range of distinct physicochemical properties that are ideal for many biomedical purposes. Some of the different applications of nanomaterials within medicine include drug delivery, tissue engineering, bio-micromechanical systems (bioMEMS), biosensors, microfluidics, and diagnostics. Of these, nanomaterial-based drug delivery systems have emerged as one of the primary uses of nanotechnology within medicine.
The small size of nanomaterials is mainly responsible for their various advantageous properties. For drug delivery systems, nanomaterials have not only improved the targeting specificity of these drugs but have also improved circulation time, biodistribution, solubility, intracellular delivery, and ability to cross biological membranes. For cancer treatment purposes, nanocarriers have also been found to allow for drugs to accumulate at high levels at the tumor site.
An Overview of Inorganic Nanomaterials
Inorganic nanoparticles (INPs) have been widely studied over the past several decades for a wide variety of industrial purposes. Within the field of biomedicine, INPs have been utilized for both diagnostic and therapeutic purposes.
For example, gold nanoparticles (AuNPs) have been widely studied due to their biocompatibility and the ease of controlling their size distribution and shape, which can include spheres, nanorods, and cubes, among others. Furthermore, the surface chemistry of AuNPs can also be easily modified through conjugation with various polymers, antibodies, small-molecule therapeutics, and molecular probes.
Another prevalent type of INP includes iron oxide nanoparticles (IONPs), which have been widely used since the 1960s for diagnostic imaging and therapeutic purposes. To date, the United States Food and Drug Administration (FDA) has approved several IONPs for both therapeutic and imaging use. In particular, magnetite (Fe3O4) nanoparticles have been used as a contrast agent for magnetic resonance imaging (MRI) due to their extremely low cytotoxicity profile, magnetic responsiveness, tunability, and controlled size and surface modification.
MSNPs have also been studied for their use as stimuli-responsive drug release systems. In this application, the surface of MSNPs can be manipulated to adjust the controlled release of the encapsulated drug after a trigger reaction occurs. Some of the different medications that have been incorporated into MSNP-based drug delivery systems include vancomycin and adenosine triphosphate (ATP).
An Overview of Organic Nanomaterials
Several organic-based nanomaterials, including liposomes, micelles, and polymer nanoparticles, have been developed for drug delivery purposes.
Liposomes, for example, or a type of lipid-based nanomaterial that consists of an aqueous core surrounded by a phospholipid bilayer. This structure is therefore amphiphilic and allows for the formation of a thermodynamically stabilized vesicle. Some of the most common types of phospholipids that are often incorporated into liposomes include phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylserine, and phosphatidylglycerol. In addition to these phospholipids, stabilizers like cholesterol are also often incorporated into a liposome to increase their stability.
As drug delivery vehicles, liposomes have been shown to improve the permeation of hydrophilic drugs, protect peptides and other protein-based drugs against harsh conditions like the stomach’s acidity, improve the bioavailability of drugs, as well as reduce toxicity and adverse side effects. Notably, the targeting ability and rate of drug release of liposomes depend on the type of lipid incorporated into the liposome and their size, lamellarity, and surface properties.
Applications in Cancer Treatment
Both INPs and organic nanoparticles have been widely studied for their use as drug delivery vehicles for anticancer drugs. For example, AuNPs and IONPs and their combination have been explored for HER2 receptor-based targeting of drugs for the treatment of breast cancer.
Several other HER2-based targeting treatments have been developed based on modified nanocarriers to improve the therapeutic efficacy of specific antineoplastic agents. For example, one recent study discussed the development of trastuzumab conjugated pH-sensitive double-emulsion nanocapsules (DENCs) that are stabilized by both poly (vinyl alcohol) and magnetic nanoparticles. In this work, the researchers used these nanocarriers for the co-delivery of doxorubicin (DOX) and paclitaxel, which were found to improve the targeting ability of these drugs towards HER2 positive breast cancer cells.
The first FDA-approved nanodrug was Doxil®, which is a PEGylated liposomal DOX formulation that passively targets tumors via the enhanced permeability and retention (EPR) effect. Importantly, Doxil® is associated with significantly reduced cardiotoxicity as compared to when DOX is used alone.
Challenges
Despite the numerous advantages associated with both INPs and organic nanoparticles as drug delivery vehicles, several major challenges still account for their limited clinical use. One of the most significant issues includes the regulatory mechanisms currently in place for nanomedicines and the safety and toxicity assessments that need to be better tailored for nanomedical applications….

News
Nanocrystals Carrying Radioisotopes Offer New Hope for Cancer Treatment
The Science Scientists have developed tiny nanocrystal particles made up of isotopes of the elements lanthanum, vanadium, and oxygen for use in treating cancer. These crystals are smaller than many microbes and can carry isotopes of [...]
New Once-a-Week Shot Promises Life-Changing Relief for Parkinson’s Patients
A once-a-week shot from Australian scientists could spare people with Parkinson’s the grind of taking pills several times a day. The tiny, biodegradable gel sits under the skin and releases steady doses of two [...]
Weekly injectable drug offers hope for Parkinson’s patients
A new weekly injectable drug could transform the lives of more than eight million people living with Parkinson's disease, potentially replacing the need for multiple daily tablets. Scientists from the University of South Australia [...]
Most Plastic in the Ocean Is Invisible—And Deadly
Nanoplastics—particles smaller than a human hair—can pass through cell walls and enter the food web. New research suggest 27 million metric tons of nanoplastics are spread across just the top layer of the North [...]
Repurposed drugs could calm the immune system’s response to nanomedicine
An international study led by researchers at the University of Colorado Anschutz Medical Campus has identified a promising strategy to enhance the safety of nanomedicines, advanced therapies often used in cancer and vaccine treatments, [...]
Nano-Enhanced Hydrogel Strategies for Cartilage Repair
A recent article in Engineering describes the development of a protein-based nanocomposite hydrogel designed to deliver two therapeutic agents—dexamethasone (Dex) and kartogenin (KGN)—to support cartilage repair. The hydrogel is engineered to modulate immune responses and promote [...]
New Cancer Drug Blocks Tumors Without Debilitating Side Effects
A new drug targets RAS-PI3Kα pathways without harmful side effects. It was developed using high-performance computing and AI. A new cancer drug candidate, developed through a collaboration between Lawrence Livermore National Laboratory (LLNL), BridgeBio Oncology [...]
Scientists Are Pretty Close to Replicating the First Thing That Ever Lived
For 400 million years, a leading hypothesis claims, Earth was an “RNA World,” meaning that life must’ve first replicated from RNA before the arrival of proteins and DNA. Unfortunately, scientists have failed to find [...]
Why ‘Peniaphobia’ Is Exploding Among Young People (And Why We Should Be Concerned)
An insidious illness is taking hold among a growing proportion of young people. Little known to the general public, peniaphobia—the fear of becoming poor—is gaining ground among teens and young adults. Discover the causes [...]
Team finds flawed data in recent study relevant to coronavirus antiviral development
The COVID pandemic illustrated how urgently we need antiviral medications capable of treating coronavirus infections. To aid this effort, researchers quickly homed in on part of SARS-CoV-2's molecular structure known as the NiRAN domain—an [...]
Drug-Coated Neural Implants Reduce Immune Rejection
Summary: A new study shows that coating neural prosthetic implants with the anti-inflammatory drug dexamethasone helps reduce the body’s immune response and scar tissue formation. This strategy enhances the long-term performance and stability of electrodes [...]
Scientists discover cancer-fighting bacteria that ‘soak up’ forever chemicals in the body
A family of healthy bacteria may help 'soak up' toxic forever chemicals in the body, warding off their cancerous effects. Forever chemicals, also known as PFAS (per- and polyfluoroalkyl substances), are toxic chemicals that [...]
Johns Hopkins Researchers Uncover a New Way To Kill Cancer Cells
A new study reveals that blocking ribosomal RNA production rewires cancer cell behavior and could help treat genetically unstable tumors. Researchers at the Johns Hopkins Kimmel Cancer Center and the Department of Radiation Oncology and Molecular [...]
AI matches doctors in mapping lung tumors for radiation therapy
In radiation therapy, precision can save lives. Oncologists must carefully map the size and location of a tumor before delivering high-dose radiation to destroy cancer cells while sparing healthy tissue. But this process, called [...]
Scientists Finally “See” Key Protein That Controls Inflammation
Researchers used advanced microscopy to uncover important protein structures. For the first time, two important protein structures in the human body are being visualized, thanks in part to cutting-edge technology at the University of [...]
AI tool detects 9 types of dementia from a single brain scan
Mayo Clinic researchers have developed a new artificial intelligence (AI) tool that helps clinicians identify brain activity patterns linked to nine types of dementia, including Alzheimer's disease, using a single, widely available scan—a transformative [...]