Spiky nanorobots powered by magnets have been developed to carry drugs and pierce tumour cell membranes, a key barrier to effective cancer treatment.
By boosting drug entry, these “microscopic scalpels” have been shown to improve chemotherapy results in laboratory and animal studies, suppressing tumour growth and extending survival.
Getting chemotherapy drugs past a cancer cell’s protective shield is one of the toughest challenges in oncology.
Tumour cells defend themselves by forming rigid membranes that block medicine from entering. Even when drugs do get inside, many cancer cells use “efflux pumps” to push them straight back out, leading to drug resistance.
These defences often make chemotherapy less effective, especially in aggressive or late-stage cancers, when time is of the essence.
To address this problem, a group of experts have teamed up to introduce a new strategy involving spiky nanorobots powered by magnets.
These tiny machines function like tiny scalpels, enabling them to penetrate tumour defences and enhance the effectiveness of chemotherapy drugs.
The study, published in Research, was co-led by Dr Zhilu Yang from The Tenth Affiliated Hospital, Southern Medical University, Dr Xing Ma from Harbin Institute of Technology (Shenzhen) and Dr Ning Liu from Tongji University, China.
In laboratory and animal experiments, the nanorobots increased drug penetration into tumour cells, suppressed tumour growth and even extended survival rates, demonstrating how these nanorobots improve drug delivery and treatment outcomes.
“These nanorobots essentially act as mechanical agitators,” explains Dr Liu.
“By rotating under a magnetic field, their sharp spikes disrupt the cell membrane, creating tiny openings that allow drugs to slip inside more efficiently.”
Drug delivery encounters two main challenges: the cell membrane and drug-resistant tumour cells that expel medication.
Whilst nanocarriers such as liposomes have made some progress, they still have limitations regarding stability, targeting and drug release. A new approach using nanorobots overcomes these issues by physically opening the cell's barrier.
The researchers designed the robots using gold nanospikes about 500 nanometers wide — roughly 200 times thinner than a human hair.
A nickel coating made them responsive to magnets, while titanium improved safety inside the body.
Under an external magnetic field, the nanorobots could be guided to tumours and spun in place. Their jagged spikes then pierced cell membranes, generating localised pressure strong enough to create “pores” for drugs to pass through.
In experiments with human liver cancer cells, robots significantly increased the uptake of doxorubicin, a standard chemotherapy drug.
Longer application of the magnetic field led to greater drug entry, with fluorescence imaging showing much higher concentrations inside the cells.
These results were consistent across different tumour types, including cervical and colon cancer models.
“Think of it as giving the drug a shortcut,” says Dr Ma, “Instead of relying on slow diffusion or being blocked by resistance mechanisms, the nanorobots create a mechanical pathway that drugs can use to reach the inside of the cell directly.”
Computer simulations have also confirmed these findings, demonstrating that as the spikes rotated, they created pores in the membrane, which increased its permeability.
Over time, the robots not only increased drug uptake but also directly damaged cancer cells through a process that the researchers refer to as "mechano-killing."
The team also tested their approach on mice with liver tumours.
The group treated with both nanorobots and chemotherapy showed a 61% reduction in tumour growth and a 100% survival rate, with improved overall health compared with those given only chemotherapy or magnetic stimulation.
Tissue analysis confirmed higher cancer cell death and minimal side effects, indicating strong safety potential.
“This dual approach of combining chemotherapy with mechanical disruption represents a powerful new direction for cancer treatment,” says Dr Yang.
“It shows that physical forces, when applied at the nanoscale, can work hand-in-hand with drugs to overcome cancer’s defences.”
Whilst the results are promising, the technology is still in its early stages. More work is required before testing spiky nanorobots on humans, including design refinement, long-term safety and improved delivery methods.
However, overall, the results represent a promising advancement.
By transforming nanorobots into microscopic scalpels, these scientists have shown that it may be possible to physically cut through cancer’s shield, making treatments more effective, less toxic and better suited to the fight against drug-resistant disease.