Lithium borate

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Lithium boric acid
Image:Lithium borate.jpg
Other names	Lithium borate
Identifiers
CAS number	[12007-60-2]
Properties
Molecular formula	Li₂B₄O₇
Molar mass	169.11 g/mol
Appearance	white powder
Density	2.4 g/cm³, solid
Melting point	917°C
Solubility in water	moderately soluble
Hazards
MSDS	External MSDS
NFPA 704	0 2 0
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

Lithium borate (Li₂ B₄ O₇) is the lithium salt of boric acid.

[edit] Uses

Lithium borate can be used in the laboratory as buffer for gel electrophoresis of DNA and RNA. It has a lower conductivity, produces crisper resolution, and can be run at higher speeds than can gels made from TBE or TAE (5-50V/cm as compared to 5-10V/cm). At a given voltage, the heat generation and thus the gel temperature is much lower than with TBE/TAE buffers, therefore the voltage can be increased to speed up electrophoresis so that a gel run takes only a fraction of the usual time. Downstream applications, such as isolation of DNA from a gel slice or Southern blot analysis, work as expected with lithium boric acid gels. Lithium borate is also an ingredient for use in making glasses and ceramics.

The recipe for 1 liter of 20X lithium borate (LB) DNA electrophoresis buffer is as follows: To 950 mL of dH2O, add 8.392 g of lithium hydroxide monohydrate and 36 g of boric acid, pH should be near 8.2. Adjust volume to 1 L and filter sterilize. This yields a final working concentration of ~10 mM lithium borate and a pH of 8.5. No EDTA is used because this would increase conductivity and is unnecessary in most applications.(adapted from^[1])

Sodium borate is similar to lithium borate and has nearly all of its advantages at a somewhat lower cost, but the lithium buffer permits use of even higher voltages due to the lower conductivity of lithium ions as compared to sodium ions.