5 replies to this topic

[Mad researcher]

Is this recipe for SB buffer correct? i found it online. If not, can you give me the correct recipe please?

SODIUM BORATE BUFFER

50x Stock:
  
20 g NaOH
pH to 8.0 with approx 120 g H₃BO₃ (boric acid powder)
bring to 1 L with dH₂O

NOTE:  This stock will precipitate over time, requiring heat to re-dissolve crystallized salts before dilution.


1x Working Buffer:

20 ml of 50x stock
980 ml dH2O
  
NOTE:  The pH of the working solution will be higher than that of the 50x stock
NOTE:  Do not re-use 1x solution for more than a day or it will go fuzzy.  Really.


Translated to concentrations:

50x Stock:  500 mM NaOH, pHed to 8.0 w/ H₃BO₃
1x Working buffer:  10 mM NaOH, pHed to 8.5 w/ H₃BO₃

Just removed your duplicated post bits.  Bob

[bob1]

Those look correct to me.

I re-use SB several times, sometimes even over a month or so I will use the same buffer.  find it slows down after about 5x reuse.

[Mad researcher]

I like the SB buffer and i have replaced my TBE buffer with SB buffer. It was quite fast :-)

[Mad researcher]

What voltage do you prefer while using SB buffer and for how much time?

[bob1]

Depends on the size of the product I am looking for.  Typical PCR of 500 ish bp, and I would go 300 V for 6 -10 min.

[Mad researcher]

I have 300 bp products and i run it at 150 V for 40 mts.
I am planning to increase the voltage to 250 V and reduce the time to 20 mts.