Showing posts with label Nanostring. Show all posts
Showing posts with label Nanostring. Show all posts

Thursday, March 3, 2011

It is a cold harsh world: Lessons in shipping with dry ice

Two week ago Assaf completed a large scale experiment with the robot. The next step was sending all the samples to Ollie's lab for running the NanoString assays. This involved sending cellular extracts with RNA from ~900 samples. Since the samples are sensitive, they need to be kept cold, and so should be shipped expediently packaged with dry ice to keep the temperature.

It turned out that this is a non-trivial exercise. In our previous iteration, we learned where to order dry ice. Now, however, we needed a much larger box as we were sending hundreds of tubes. 

Assaf used the robot to move the samples into 12-strips of small tubes, organized in 96-well format by using tip boxes.



Ayelet and Assaf then sat down and labeled the strips and packed them in boxes. They sealed the boxes with parafilm to keep everything in place. 



Assaf and I packed the insulating polystyrene box with blocks of dry ice, and arranged the boxes on top of them. Finally we sealed the box tightly and shipped it to UMass.


After three days, we get an email titled "Disaster!". When the UMass people opened the box they found small rocks of dry ice and many fragments of plastic scattered throughout the box (although few boxes remained intact).



(pictures courtesy of Ollie's iPhone)

The lessons we learned from the exercise is a harsh one. Turns out that the plastic strips we use are extremely brittle at cold temperature. Moreover, parafilm no longer binds when cold. Moreover, as the ice blocks evaporate, there is room for play inside the box, and things start to jump around, leading to havoc.

Monday, February 21, 2011

Robotic NanoString Experiment

Today was finished our first large scale experiment using our robotic platform. 

Assaf programmed the robot to grow 90+ strains of yeast over two days to reach optimal conditions (as I previously described), then the robot stimulated them and harvested cells at 9 time points. Each harvesting step involved taking small amount of cells from the plate they were growing them and plunging them into a plate of cold liquid methanol. This immediately freezes the cells and "stops" them cold (literally).

Next, Assaf used the protocol he and Ayelet devised for extracting RNA from yeast cells, to process these 9 x 96well plates. These will be shipped to Ollie's lab for running the NanoString assay to measure exact RNA quantities.

This was the first time we had an actual experiment running from start to finish. Although we "debugged" various parts before, putting all of them together uncovered all types of problems. Assaf had to restart the growth several time before we had the whole thing running. But now we are smarter and know how to get things right the next time.

After few days of heavy robot use, Assaf collected all the plasticware he used. Here is a picture of triumphant Assaf at the end of the process.