A Taiwan research team has developed a new approach for investigating the amount of nano-/microparticles taken up by mammalian cells. This project was led by Dr. Chung-Hsuan Chen, Distinguished Research Fellow and Director of the Genomics Research Center (GRC) at Academia Sinica, and Dr. Wen-Ping Peng, a Jointly-appointed Assistant Professor of the GRC and the Department of Physics at National Dong Hwa University of Taiwan, in collaboration with Dr. Alice Yu, Distinguished Research Fellow and Deputy Director of the GRC. The research was published online in the leading international journal, Angewandte Chemie, on April 13, 2010.

Nano-/microparticles have been pursued by researchers in recent years as possible carriers for drug delivery. Therefore, effective quantitative measurement of the cellular uptake of nano-/microparticles is of great importance. Conventionally these tiny particles have been measured using certain types of mass spectrometry (an analytical technique for the determination of the elemental composition of a sample or molecule) including Inductively Coupled Plasma Atomic Emission Spectroscopy and Inductively Coupled Plasma Mass Spectrometry (ICP-MS). However, these methods of measurement are limited to elemental particles such as gold nanoparticles.

For this study, scientists used a different type of spectrometer called the Charge-Monitoring Mass Spectrometer (CMS), a device which was itself developed by a group at the GRC and the Institute of Atomic and Molecular Sciences at Academia Sinica in 2007 to measure single cancer cells at higher speeds. This time, researchers from the GRC Physical and Computational Genomics group used this recently-developed device to measure the masses of cells of nano-/microparticle, a novel approach for investigating the amount of nano-/microparticle uptake into mammalian cells.

The group’s findings indicate that the CMS is an adequate tool for time-resolved measurements of nanogold uptake by cells. They also found that the CMS could measure particles over a larger size range from 30nm to 250 nm. In addition, as the CMS only takes two-steps to examine the nanogold and the ICP-MS takes five-steps rendering the CMS analysis is more time-efficient. Most importantly, however, the CMS will also be able to measure non-metal nano particles, including polymeric nanoparticles, carbon nanotubes, diamond nanoparticles, viruses, micelles and liposomes in addition to elemental particles.

“This research brings more efficiency to the measurement and detection of the mass changes of a cell as a result of malignancy or the uptake of nanoparticles. The CMS is proven to be useful in streamlining the determination the quantity of both gold and polystyrene nano-/microparticles taken up into cells. We expect that such device will be of importance in medical applications,” noted the first author of the study, Huan-Chang Lin, a Ph.D. candidate in the Department of Bio-Industrial Mechatronics Engineering at National Taiwan University.

This research is co-funded by the National Science Council, Academia Sinica and the National Health Research Institute. The full list of authors is Huan-Chang Lin, Hsin-Hung Lin, Cai-Yu Kao, Alice L. Yu, Wen-Ping Peng and Chung-Hsuan Chen.

The full-text of the study was published under the title Quantitative Measurement of Nano-/Microparticle Endocytosis by Cell Mass Spectrometry, available at the Angewandte Chemie website at:

http://www3.interscience.wiley.com/journal/123349954/abstract?CRETRY=1&SRETRY=0.

Angewandte Chemie is published by the German Chemical Society. In 2008 it had an impact factor of 10.879.

Dr. Chung-Hsuan Chen, Genomics Center, Academia Sinica

(Tel) +886-2-2787-1200

Dr. Wen-Ping Peng, Department of Physics, National Dong Hwa University

(Tel) +886-3-8633-733

Fang-Hsun Yeh, Public Relations Office, Central Office of Administration, Academia Sinica (Tel) +886-2-2789-8824, (M) 0922-036-691, hongsum@gate.sinica.edu.tw