What are the effects of temperature on HPLC analysis?
Thread Content
The air conditioning in our analysis room is broken, and the temperature difference has been quite large lately. Using the same analysis method, the patterns obtained on the second day always differed from those of the previous day, indicating quite poor reproducibility. I would like to ask: just how significant is the impact of temperature on HPLC analysis? Which specific aspects are affected?
This post was last edited by zbx on 2009-12-29 at 21:17. The optimal operating temperature for HPLC is between 20 and 25 degrees; large temperature differences can have a significant impact on retention times. Are your chromatography columns placed in a thermostat? If so, the changes will be limited. Also, has there been any change in the composition of your mobile phase? Changes in the mobile phase composition can also lead to substantial variations in retention times.
The column thermostat broke down very early on; this problem has existed for a long time and has yet to be resolved. Is there any way to repair or replace it? It’s also impossible to get in touch with the manufacturer now.
Reply to the moderator: The device was purchased a long time ago, around 2004. It is German equipment, KNAUER; the pump model is K-501, and the UV detector model is K-2501. After it was purchased, it was said that it didn’t work very well at the time, so it was left unused; it wasn’t brought back into use until last year. I came to this analysis lab at the beginning of this year, so I can’t find the original manufacturer at all.
You can contact the distributors of German companies on the Chinese mainland; you probably don’t import directly from Germany, right? Or find the original purchase invoice to see through which channel the product was bought, and then get in touch.
I tried to find German companies’ distributors on the Chinese mainland, but it seems I couldn’t locate any. PS: If anyone knows, please pass the message along! Thanks! As for the details of those purchases at that time, no one in the company knows about them anymore; haha, what a pity~~~ (It is said that they were left unused ever since they were purchased, with no one paying attention to them. Attempts to check the records in the finance department were met with refusal, as too much time has passed – it’s not really considered a big issue~~~)
The regular moderator is an expert in instruments, but they can’t necessarily help you with lookups.
Okay, thank you, moderator! :loveliness:
I took a look; it seems to mean the same thing: high-pressure liquid phase, the temperature control is broken. Although I’ve never worked with liquid phases, for chromatography the three key elements are temperature, pressure, and flow rate. If one of these is compromised, the instrument becomes unusable – unless you identify the cause of the problem with temperature control and fix it! The pump is a complementary product; first find the original model of the instrument. Also, first check if it’s the heating wire that’s burned out Did the fuse blow? Is it still the temperature control circuit board? Contact the manufacturer while simultaneously trying to find the cause yourself. I haven’t used this kind of UV detector either; I’ll ask around. This post was last edited by chengjingbao on 2009-3-27 21:06]
I looked for it today; the original temperature control box can no longer be found. I’m currently using a domestic one, from Hanbang, but it’s broken.
1. Remove the temperature control unit from your instrument and give it to the instrumentation technician; there are basically three possible issues: a faulty fuse, a problem with the heating element, or a faulty temperature control unit. All of these can be easily checked. 2. If the temperature control unit is damaged, it generally does not affect the analysis process, so you can use an air conditioner to maintain a constant temperature. 3. Clean the dust from your instrument; it is also recommended not to turn it on right away. For devices that have not been used for a long time, it is best to have an expert diagnose them before turning them on. 4. If you still encounter problems, you can contact me via text message
Thank you to the moderator for their support! The condition of the instrument’s surface is still fine; at the moment, I really want to take apart the detection cell to take a look.
For the detection cell, you can wash the empty column; if you are not very familiar with its structure, it is recommended that you do not make any changes. If you do decide to make changes, wait until you have thoroughly understood the instructions. Remember, the true heart of a liquid chromatograph is the pump, but the detector is also something that a novice analyst can adjust – proceed with caution
A forum member helped me find out that the general agent for Nor in Germany in China is Beijing ChuangXinTongHeng. Unfortunately, their website is in English; why don’t you take a look? If there really is something belonging to you, reply to confirm. http://www.knauer.net/e/e_index.html?cf=
Can I buy another one? From what you say, the possibility of repair is low.
It’s best not to touch the UV detector for now; if you really want to do so, it’s advisable to first watch a video on its structure and the maintenance procedures. If you have such an intention, post it here and I’ll see if I can prepare a complete set of materials for you. It’s fine if there isn’t one. If you’re not sure, it’s best not to move!
Okay, thank you to the moderator for the help. I also checked Beijing Xintongheng’s website and even contacted their office, but got nothing out of it. As for the “video on UV detector structure and maintenance steps,” I really would like to learn about it*; I’d appreciate it if the moderator could help, hehe :)