We have discussed many topics about the rotary evaporator in previous articles, for instance, how to use a rotary evaporator, how to install a rotary flask evaporator, how to maintain a rotary flask evaporator, and rotary evaporator cannabis extraction method, etc.. In this paper, the author would like to make a brief introduction to the two frequently asked questions on the rotary evaporator.
The first question: How can I evaporate water and ethanol by using a rotary evaporator?
Background: I found my rotary flask evaporator was very slow(4 hours to evaporate 500mL solution) when I’m trying to evaporate ethanol and water, which also contain milk protein. How can I optimize the rotary flask evaporator?
Answer A: You could shift the temperature for quicker evaporation. However, since you have rich proteins in the solution, it doesn't seem wired at all that you take all that time to evaporate the solution (loads of hydrogen bonding!). However,you may have your protein (if it is indeed your goal!) by increasing the temperature.
Answer B: I would like to recommend a vacuum pump to further lower pressure and offering high pumping capacity. Even without elevating temperature, all solution can be evaporated. Pumping it with a vacuum pump which can attain pressure lower than vapour pressure of the solution which you want to evaporate.
Answer C: First you need to determine the percentage of the ethanol inside. After several times, the composition left in the flask will be different; so that you might adding 5 more degree from the boiling point of the mixture.
The second question: Are there alternatives to Nitrogen drying for evaporating chloroform from lipids?
Background: I am following a protocol for extracting lipids from liver tissue for a cholesterol assay. The protocol calls for adding a 2:1 chloroform:methanol mixture, homogenizing, and rotating at 4C overnight. The next day, KH2PO4 is added and the mixture is split into three phases. The lower phase contains the lipids as well as chloroform, which must then be evaporated by drying in a stream of nitrogen.
I do not have access to inert gas, so I was looking for an alternative to this step. I read somewhere that an air stream can be used if hydro is added to prevent oxidation. I don't have access to a speed vac either. Could I just evaporate the chloroform in the hood for a few hours without compromising the samples?
Answer A: A rotary evaporator could solve your problem(40°C maximum temperature of the bath).
Answer B: If you are going to measure only cholesterol, you don't need a speed vac, rotary flask evaporator or even nitrogen stream. Just adding 0.1% of hydro to your samples, and let them evaporate overnight in a fume hood. It works perfectly, and the samples will not suffer. But you can do that if you are planning to quantify cholesterol only. Do not even bother to measure fatty acids, composition or other lipid species. It won't work.
Answer C: Even if you don't have a Speed Vac or rotary evaporator, you can simply use a regular vacuum pump to strip off the solvent. What you need is a clean rubber hose , a vent and a glass trap immersed in ice cold water.
The above mentioned text is the two frequently asked questions on the rotary evaporator. If you want to know more about this, please contact with the henan lanphan. Lanphan is a qualified company which boats a fine reputation both home and abroad, and lanphan is also a manufacturer of the rotary evaporator. If you want to purchase the rotovap, please contact with the lanphan, we are willing to provide the best service. Our emain adress is the [email protected]
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