Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Quantum dots light the way

21.07.2015

A drug-encapsulating nanoparticle teams up with bright bio-labels to measure how anticancer chemotherapy formulations enter cells

Polymer nanoparticles that release medicine at controlled rates inside cells have the potential to enhance the efficacy of many clinical drugs. A*STAR researchers have now developed an eye-catching way to evaluate the performance of different polymer drug-delivery formulations using luminescent quantum dots as imaging labels1.


Confocal images of quantum dots localized within colon cells can guide the development of innovative drug delivery formulations.

Reproduced, with permission, from Ref. 1 © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Tiny, inorganic quantum-dot crystals are finding increasing use as biological probes due to their powerful optical characteristics. By stimulating the dots with laser light, researchers can obtain sharp images to monitor processes such as drug delivery for much longer time frames than nearly any other technique. However, a key challenge lies in incorporating hydrophobic quantum dots into biocompatible, water-soluble polymers.

Ming-Yong Han and co-workers from the A*STAR Institute of Materials Research and Engineering in Singapore turned to a copolymer known as poly(D,L-lactide-co-glycolide), or PLGA, for their quantum-dot imaging strategy. This non-toxic material has tunable water-repelling or water-attracting ability, depending on the proportion of lactic and glycolic acid components. It is also an ideal drug delivery platform for the popular anticancer drug doxorubicin — a fluorescent molecule used to treat diseases including leukemia and Hodgkin’s lymphoma.

“The choice of polymer and nanoparticle preparations plays an important role in making uniformly fluorescent particles,” says co-author Choon Peng Teng. “Different hydrophobic or hydrophilic interactions affect how quantum dots are incorporated.”

The team synthesized two kinds of PLGA nanoparticles — one loaded with doxorubicin, and the other containing quantum-dot bio-labels — and incubated them in a culture of human colon cells. After two hours, confocal imaging revealed that both kinds of polymer nanoparticles were engulfed by the cells through an endocytosis mechanism and internalized into the cytoplasm (see image). The bright emissions from the dots enabled the researchers to quantify the uptake as 25 per cent of the cell volume.

Since the behavior of the quantum dot-labeled nanoparticles paralleled the doxorubicin-impregnated materials, Han and colleagues realized this imaging system could model the effectiveness of other important drug-delivery schemes. Initial investigations appear promising — the quantum-dot-loaded PLGA nanoparticles mimicked different drug-delivery systems for targeting brain, lung and breast cancer cell lines, and were compatible with both water-soluble and water-insoluble drugs.

One further advantage of this approach, notes co-author Khin Yin Win, is that it can simulate the action of non-fluorescent anticancer drugs previously untraceable with confocal imaging. “This model can facilitate monitoring biocompatibility and cellular uptake, but it can also evaluate how feasible certain materials are as drug carriers,” she says. “This could lead to more innovative drug-delivery systems.”

The A*STAR-affiliated researchers contributing to this research are from the Institute of Materials Research and Engineering. More information about the group’s research can be found at the Synthesis & Integration group webpage.

Reference
Win, K. Y., Teng, C. P., Ye, E., Low, M. & Han, M.-Y. Evaluation of polymeric nanoparticle formulations by effective imaging and quantitation of cellular uptake for controlled delivery of doxorubicin. Small 11, 1197–1204 (2015). | article

A*STAR Research | ResearchSEA
Further information:
http://www.research.a-star.edu.sg/research/7324
http://www.researchsea.com

More articles from Materials Sciences:

nachricht InLight study: insights into chemical processes using light
05.12.2016 | Fraunhofer-Institut für Lasertechnik ILT

nachricht Physics, photosynthesis and solar cells
01.12.2016 | University of California - Riverside

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

IHP presents the fastest silicon-based transistor in the world

05.12.2016 | Power and Electrical Engineering

InLight study: insights into chemical processes using light

05.12.2016 | Materials Sciences

High-precision magnetic field sensing

05.12.2016 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>