4 replies to this topic

[Maddie]

Hi everyone,

Does someone here uses the Qubit™Quantitation Kit from Invitrogen to quantify DNA?
I'm interested in bying it but I'd like to have feedback from people who use it if possible.
Thanks

Maddie

[hobglobin]

Maddie, on 15 September 2010 - 06:26 AM, said:

Hi everyone,

Does someone here uses the Qubit™Quantitation Kit from Invitrogen to quantify DNA?
I'm interested in bying it but I'd like to have feedback from people who use it if possible.
Thanks

Maddie

We use it regularly, but actually I've not really an idea how exact the values are. The advantages are that it is really easy to use, it's very fast to use and handling errors seem unlikely. Due to the different fluorescent dyes, it really measures only what you need (i.e. DNA, RNA or proteins) due to specifically binding of the different dyes.
But there are of course several disadvantages: Pipetting errors are more likely compared to other systems as you have to make dilution steps (though in other spectrophotometers too), the fluorescent dyes are expensive (you need different ones for different probes and concentrations; the tubes may be too expensive), you won't get an idea about purity of the samples (by calculating different ratios).

Here is a of course heavily biased comparison by Invitrogen.

[Maddie]

Quote

We use it regularly, but actually I've not really an idea how exact the values are. The advantages are that it is really easy to use, it's very fast to use and handling errors seem unlikely. Due to the different fluorescent dyes, it really measures only what you need (i.e. DNA, RNA or proteins) due to specifically binding of the different dyes.
But there are of course several disadvantages: Pipetting errors are more likely compared to other systems as you have to make dilution steps (though in other spectrophotometers too), the fluorescent dyes are expensive (you need different ones for different probes and concentrations; the tubes may be too expensive), you won't get an idea about purity of the samples (by calculating different ratios).

Here is a of course heavily biased comparison by Invitrogen.

Thanks   . The reason I want to try it is because the nanodrop is totally inaccurate when it comes to low DNA concentrations. Also the numbers are biaised by ssDNA and, more problematic for me, by humic acids. Do you know if the dyes from the Qubit would bind to humic acids?
I agree that the dilution can bring extra errors but what I like here is that you can use more than 1 or 2ul. I doubt I'd have 20ul to waste for that but hopefully 5 to 8ul would be enough to get something above 100pg/ul.
So I guess the instrument measures total amount of dsDNA and then divides the # by the volume you used to get a concentration, right?
Concerning the fluorometer, is it good quality? Did it ever break?

[i.m]

Maddie, on 15 September 2010 - 07:25 AM, said:

Quote

We use it regularly, but actually I've not really an idea how exact the values are. The advantages are that it is really easy to use, it's very fast to use and handling errors seem unlikely. Due to the different fluorescent dyes, it really measures only what you need (i.e. DNA, RNA or proteins) due to specifically binding of the different dyes.
But there are of course several disadvantages: Pipetting errors are more likely compared to other systems as you have to make dilution steps (though in other spectrophotometers too), the fluorescent dyes are expensive (you need different ones for different probes and concentrations; the tubes may be too expensive), you won't get an idea about purity of the samples (by calculating different ratios).

Here is a of course heavily biased comparison by Invitrogen.

Thanks   . The reason I want to try it is because the nanodrop is totally inaccurate when it comes to low DNA concentrations. Also the numbers are biaised by ssDNA and, more problematic for me, by humic acids. Do you know if the dyes from the Qubit would bind to humic acids?
I agree that the dilution can bring extra errors but what I like here is that you can use more than 1 or 2ul. I doubt I'd have 20ul to waste for that but hopefully 5 to 8ul would be enough to get something above 100pg/ul.
So I guess the instrument measures total amount of dsDNA and then divides the # by the volume you used to get a concentration, right?
Concerning the fluorometer, is it good quality? Did it ever break?

Hello!
I recently started using the Qubic to quntify RNA extracted from soil samples. In most cases it was ok, but for some samples though I had a good band on the gel the reading was really low to count. Same happend after repeated these samples. It so happens that these ones where the "dirtiest" after the extraction, with the pellet looking rather dark.So i was wondering if humic acids may be the problem. Have you (or anybody else)found out if the dyes can bind to the humic acids?

[i.m]

Maddie, on 15 September 2010 - 07:25 AM, said:

Quote

We use it regularly, but actually I've not really an idea how exact the values are. The advantages are that it is really easy to use, it's very fast to use and handling errors seem unlikely. Due to the different fluorescent dyes, it really measures only what you need (i.e. DNA, RNA or proteins) due to specifically binding of the different dyes.
But there are of course several disadvantages: Pipetting errors are more likely compared to other systems as you have to make dilution steps (though in other spectrophotometers too), the fluorescent dyes are expensive (you need different ones for different probes and concentrations; the tubes may be too expensive), you won't get an idea about purity of the samples (by calculating different ratios).

Here is a of course heavily biased comparison by Invitrogen.

Thanks   . The reason I want to try it is because the nanodrop is totally inaccurate when it comes to low DNA concentrations. Also the numbers are biaised by ssDNA and, more problematic for me, by humic acids. Do you know if the dyes from the Qubit would bind to humic acids?
I agree that the dilution can bring extra errors but what I like here is that you can use more than 1 or 2ul. I doubt I'd have 20ul to waste for that but hopefully 5 to 8ul would be enough to get something above 100pg/ul.
So I guess the instrument measures total amount of dsDNA and then divides the # by the volume you used to get a concentration, right?
Concerning the fluorometer, is it good quality? Did it ever break?

Hello!
I recently started using the Qubit to quntify RNA extracted from soil samples. In most cases it was ok, but for some samples though I had a good band on the gel the reading was really low to count. Same happend after repeated these samples. It so happens that these ones where the "dirtiest" after the extraction, with the pellet looking rather dark.So i was wondering if humic acids may be the problem. Have you (or anybody else)found out if the dyes can bind to the humic acids?