Quantum dots and cisplatin – a new direction in targeted cancer therapy

This is precisely why new methods are being sought that would allow drugs to be delivered precisely to tumour cells, while sparing healthy tissues. Among the most promising solutions are targeted drug delivery systems based on nanocarriers, particularly quantum dots (QDs).

These nanoparticles are characterized by high stability and are easily modified. They can carry therapeutic agents and release them selectively once they reach target cells. Thanks to their intrinsic fluorescence, quantum dots also allow for tracking of the drug’s pathway within the body. Moreover, their photoluminescent and photothermal properties can be utilized in photodynamic and photothermal therapies, increasing treatment effectiveness through combined therapy.

The glowing vial contains an aqueous dispersion of CdTe quantum dots modified with mercaptopropionic acid (CdTe/MPA), to which cisplatin can be attached via electrostatic interaction.

To date, quantum dots have been studied primarily as carriers for doxorubicin. Far less is known about their use in the transport of platinum-based drugs, such as cisplatin. Therefore, scientists from the Faculty of Chemistry at the Warsaw University of Technology, in their project, want to answer a key question: can ZnO quantum dots become a safe and effective carrier for cisplatin?

“We are working on a system based primarily on ZnO quantum dots combined with cisplatin,” says the project leader, Joanna Zajda, PhD. “We use ZnO QDs with a polymer shell containing functional groups that enable the attachment of the drug via coordination bonds or electrostatic interactions. Such a system should be stable in the bloodstream, while releasing cisplatin only in the acidic environment of cancer cells. Importantly, ZnO quantum dots are less toxic than the commonly used CdSe/ZnS QDs, and as they degrade, they release zinc ions, which are also harmful to cancer cells. This means that the combination of cisplatin and ZnO QDs may act synergistically, enhancing the therapeutic effect. To investigate the behaviour of these structures, we will use, among other methods, capillary electrophoresis coupled with various detection techniques,” adds Joanna Zajda, PhD. “This will allow us to assess the efficiency of forming ZnO QDs-cisplatin structures, system stability, and the degree of drug loading. We will also conduct drug release simulations using simple in vitro models that mimic conditions in the bloodstream and tumour tissue. These are demanding but crucial analyses – the next step depends on them: moving to more advanced biological studies.”

Autosampler CE – a device for capillary electrophoresis.

The research is being carried out under a National Science Centre (NCN) MINIATURA grant, entitled “Connect the dots… with anticancer cisplatin – development and characterisation of a new therapeutic system based on quantum dots.” This work forms the foundation for further preclinical studies and the development of innovative nanocarrier-based therapies.

“Our goal is to create a solution that increases the effectiveness of cancer treatment while simultaneously reducing toxicity for patients,” says Joanna Zajda, PhD. “If the efficacy of the ZnO QDs-cisplatin system is confirmed, we will gain a promising platform for safer and more targeted chemotherapy – and a new tool in the rapidly developing field of nanomedicine.”