Lithium borate
2009397
223330023
2008-07-03T16:27:19Z
Kirikou fr
5168652
{{Chembox new
| Name = Lithium boric acid
| ImageFile = Lithium_borate.jpg
<!-- | ImageSize = 200px -->
| ImageName = Lithium boric acid
| OtherNames = Lithium borate<br />
| Section1 = {{Chembox Identifiers
| CASNo = 12007-60-2
}}
| Section2 = {{Chembox Properties
| Formula = Li<sub>2</sub>B<sub>4</sub>O<sub>7</sub>
| MolarMass = 169.11 g/mol
| Appearance = white powder
| Density = 2.4 g/cm<sup>3</sup>, solid
| Solubility = moderately soluble
| MeltingPt = 917°C
| BoilingPt =
}}
| Section7 = {{Chembox Hazards
| ExternalMSDS = [http://www.physchem.ox.ac.uk/MSDS/LI/lithium_borate.html External MSDS]
| NFPA-H = 2
| NFPA-R = 0
| NFPA-F = 0
}}
}}
'''Lithium borate''' ([[Lithium|Li<sub>2</sub>]][[Boron|B<sub>4</sub>]][[Oxygen|O<sub>7</sub>]]) is the [[lithium]] [[salt]] of [[boric acid]].
==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 [[glass]]es and [[ceramic]]s.
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<ref>Brody, J.R., Kern, S.E.,Sodium boric acid: a tris-free, cooler conductive medium for DNA electrophoresis, ''BioTechniques'', 36(2), pp.214-215, 2004.</ref>)
[[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.
<!-- When dealing with lithium boric acid, avoid [[strong acid]]s. {{Fact|date=February 2007}}
Lithium Borate is a salt, not an acid. Boric acid is weak enough to be available in drug stores as an antiseptic. -->
==References==
<references/>
==External links==
* [http://www.npi.gov.au/database/substance-info/profiles/15.html National Pollutant Inventory - Boron and compounds]
[[Category:Acids]]
[[Category:Borates]]
[[Category:Lithium compounds]]
[[Category:Inorganic compound stubs]]
[[ar:بورات ليثيوم]]
[[fr:borate de lithium]]