Navigation Links
Nanoscale method for investigating living systems

By observing how tiny specks of crystal move through the layers of a biological membrane, a team of University of Wisconsin-Madison electrical and computer engineers has devised a new method for investigating living systems on the molecular level. The discovery could lead to an entirely new level of manipulation, imaging and understanding of the inner workings of cells.

The specks are known as quantum dots or inorganic semiconductor nanocrystals. Measuring in millionths of a millimeter, these dots are so small that the addition or removal of electrons changes the properties of the dot. The team, including Electrical and Computer Engineering Professors Dan van der Weide and Robert Blick with researchers Sujatha Ramachandran and George Kumar, found that by applying voltages to a solution of quantum dots and membranes similar to those of living cells, the dots would be pressed into the membranes. The dots formed rings, which in turn acted as portals in the membranes. These artificial portals or pores could enable a method of investigating living systems by means of semiconductor technology that until now could be theorized but not directly observed.

"To get a feeling of why this is important, you have to understand that each of our cell membranes has specific pores in them that regulate the flow of ions in and out," says Blick. "Through these ions, your cells will build up electric potential and communicate with other cells. This is how signal transduction is performed in your body, but it is also how chemicals react with your body. When, for example, caffeine enters a cell it stimulates the opening and closing of these ion channels. What we've found is that these quantum dots can form artificial pores that enhance the flow of ions and which we can control from the outside via voltage."

Quantum dots can be encoded with different colors making them useful as fluorescent labels for staining cells. Their resistance to photobleaching and physical siz e of less than 10 nanometers are making them increasingly popular in biomedical applications ranging from intracellular tagging of molecules to applications such as tracking devices for neuronal receptors and as interfaces between nerve cells. Researchers have labeled the dots with isotopes, injected them into mice and then tracked them with tomography.

The Wisconsin engineering team set out to use optical tagging or labeling of membrane pores in order to visualize their function and simultaneously measure their current/voltage relationship. "What we found was that quantum dots formed their own pores, which in the long run could mean that we could combine optical activity and readout with direct-current recording of cellular activity," says Blick. Because these artificial pores elicit bursts of current in the artificial membranes, the team believes quantum dots could perform similarly in other excitable cells such as neurons and muscles, and looks forward to understanding how the dots behave in vivo in excitable cells. The researchers will look next into properties that cause the artificial pores to open and close.


Source:University of Wisconsin

Related biology news :

1. Nanoscale Diagnostic Sets Sights on Alzheimers
2. Nanoscale microscope sheds first light on gene repair
3. Color-blind method opens new doors in DNA sequencing
4. New imaging method gives early indication if brain cancer therapy is effective, U-M study shows
5. Studies reveal methods viruses use to sidestep immune system
6. An entropy-based gene selection method for cancer classification using microarray data
7. New methods of gene delivery using lasers
8. Breakthrough method in nanoparticle synthesis paves the way for new pharmaceutical and biomedical applications
9. Shift of weather patterns necessitates rethinking of reforestation methods
10. Scientists use manufacturing methods to reconstruct mastodon
11. Researchers develop promising new gene network analysis method
Post Your Comments:

(Date:11/4/2015)... ALBANY, New York , November 4, 2015 /PRNewswire/ ... According to a new market report published by Transparency ... Size, Share, Growth, Trends and Forecast 2015 - 2022", ... value of US$ 30.3 bn by 2022. The market ... during the forecast period from 2015 to 2022. Rising ...
(Date:10/29/2015)... 29, 2015  Rubicon Genomics, Inc., today announced ... of its DNA library preparation products, including the ... ThruPLEX Plasma-seq kit. ThruPLEX Plasma-seq has been optimized ... NGS libraries for liquid biopsies--the analysis of cell-free ... applications in cancer and other conditions. Eurofins Scientific ...
(Date:10/27/2015)... -- Munich, Germany , October ... automatically maps data from mobile eye tracking videos created ... that they can be quantitatively analyzed with SMI,s analysis ... , October 28-29, 2015. SMI,s Automated Semantic Gaze ... tracking videos created with SMI,s Eye Tracking Glasses ...
Breaking Biology News(10 mins):
(Date:11/30/2015)... HOLLISTON, Mass. , Nov. 30, 2015 /PRNewswire/ ... HART ), a biotechnology company developing bioengineered ... has received written notification from The NASDAQ Stock ... minimum bid price requirements. The letter noted that ... of HART,s common stock having exceeded $1.00 per ...
(Date:11/30/2015)... DIEGO , Nov. 30, 2015 Human ... that the company has acquired Cypher Genomics, Inc., a ... robust human genomic interpretation software solutions. The ... will join HLI including Cypher CEO and Co-founder, Ashley ... of HLI,s Pediatric Business.  Financial details of the deal ...
(Date:11/30/2015)... and MAGDEBURG, Germany , November ... NeuroRehabilitation (ECNR) in Vienna, Austria ... European Congress of NeuroRehabilitation (ECNR) in Vienna, ... --> NovaVision, a wholly owned subsidiary of Vycor Medical, ... version of its Internet-delivered NovaVision Therapy Suite at the ...
(Date:11/27/2015)... United Kingdom , Nov. 27, 2015 /PRNewswire/--  Mallinckrodt ... biopharmaceutical company, announced today that it has closed the ... (CMDS) business to Guerbet (GBT- NYSE Euronext) in a ... operations encompassed four manufacturing facilities and a total of ... 75 in the St. Louis ...
Breaking Biology Technology: