[caption id="" align="alignright" width="350"] pliers to cut wood samples...[/caption]
The last month I have been optimizing the cellulose extraction method as I learned it at GFZ Potsdam. As most protocols are case specific some tuning is always needed. In my case I was confronted with very hard / dense wood, as common in tropical tree species. This caused serious trouble when applying the methods used in Potsdam. Mainly cutting up hard wood samples with a scalpel is dangerous at best. As such I opted to give sharp electric pliers a go. In all honesty, this works like a charm. Even for soft wood this should be the preferred method. You have far more control over the sample and don't run the risk of injuring yourself with a very sharp blade.
[caption id="" align="alignright" width="350"] Memmert hot water bath[/caption]
Other tweaks to the protocol include replacing the hot plates and glass containers to heat the samples with a Memmert hot water bath. I could borrow one from the people on the sixth floor (Food Safety lab if I'm not mistaken). This setup has a hood, a programmable thermostat and an auto refill mechanism when evaporation brings the water level below a certain level. These options take care of some of the inconveniences of the hot plate setup, mainly refilling the water bath minimizing the risk of running out of water heating the reagents. It will set me back only as much as two hot plates if I get funded. Win win...
Finally, the glass filter vials are cleaned by ashing the material left in the vials. However this method is limited by the size of the muffle furnace at hand. Given the fact that the ISOFYS lab supports varied research topics the furnaces are generally occupied. Alternatively a colleague, dr. Samuel Bodé, suggested oxidizing all material left in the vials with potassium persulfate (at 85 °C for an hour or two). This method is often used to measure the content of organic material, turning all organic material in CO2 and measuring this of-gassed CO2 content. However, in my case this method would take care of cleaning the vials using oxidation. The method is simple and will free up space in the muffle furnace.