Titration made easy

Total Lab Supplies offers a range of Titration solutions.

Titration is is a common laboratory method of quantitative chemical analysis to determine the concentration of an identified analyte (a substance to be analysed). A reagent, called the titrant or titrator, is prepared as a standard solution of known concentration and volume. The titrant reacts with a solution of analyte (which may also be called the titrand) to determine the analyte's concentration. The volume of titrant that reacted with the analyte is called the titration volume.

Total Lab Supplies supplies SI Analytics range of Titrators for all applications including Karl Fischer titration.

Karl Fischer titration is a classic titration method in chemical analysis that uses coulometric or volumetric titration to determine trace amounts of water in a sample. It was invented in 1935 by the German chemist Karl Fischer. Today, the titration is done with an automated Karl Fischer titrator.

You can’t go wrong with the new TitroLine® KF titrators from SI Analytics.

The TitroLine® 7500 KF is the volumetric generalist and the TitroLine® 7500 KF trace is the specialist for low water contents.  Both new titrators have the following features:-

• Fast, easy and precise
• With standard methods for different applications (titer, blank value, 1 or 2 component reagent)
• The addition of solvent and the extraction of the titrated sample are managed by the titration stand TM 235 KF (optional for TitroLine® 7500 KF trace
• Online display of curve and measurement drift during titration

We can also supply a FULL range of Hydranal® chemicals for use with all brands of Karl Fischer titrators.

Visit http://www.totallabsupplies.co.uk/?p=1730 for more information.

Want to extract your own DNA?

As shown recently by Professor Brian Cox on the BBC TV Series Wonders of Life it is possible using a few household ingredients to extract your own DNA.

 

DNA, or Deoxyribonucleic Acid, is the genetic material of nearly all living organisms on the planet Earth and, as such, can be called the basic building block of life. In 1953, James Watson and Francis Crick unveiled their discoveries about DNA and the double helix model, which formed the basis of genetic coding.

DNA - A Brief Description

DNA is located in the cell nucleus as the basic structure of the genes, and is composed of two strands of nucleic acid made up of units called nucleotides, wound around each other to form a double helix shape.

Nucleic acids, called that because they were discovered in cell nuclei, are long organic polymers that contain carbon, hydrogen, oxygen, nitrogen and phosphorus, forming the inherited genetic material inside each cell. In humans, each gene is a segment of DNA and controls protein synthesis, regulating most of the activities that take place in the cells.

The DNA molecule can make exact copies of itself by the process of replication, thereby passing on hereditary information - so determining all physical (and some would argue, personality) traits. This enables DNA to be used to identify gender, hair and eye colour, and other genetic markers.


To extract DNA at home you will need the following:
•saline solution (a glass of salty water)
•a clean glass
•1 tsp (5ml) washing-up liquid/detergent
•3 tsp (15ml) tap water
•a clean teaspoon
•a bottle of ice-cold alcohol (gin or vodka are excellent, as many people keep these in the freezer2. If you don't have strong booze available, any alcohol will do, such as rubbing alcohol.)
•a mouthful of spit

Method

1. Swill out your mouth with the saline solution for about 30 seconds. This is to collect the DNA contained in your saliva, and around the walls of your cheeks.
2. Spit the contents of your mouth into a glass containing a mix of three teaspoons of water and one teaspoon of washing-up liquid/detergent. You are thus (hopefully) transferring the DNA from your cheek cells into the solution.
3. Stir this mix slowly and gentlyfor a couple of minutes. During this process it is necessary to break up tissue (in this case, cheek cells) mechanically, and then to degrade both the cell membranes and those surrounding the nuclei - releasing the DNA contained within them
4. Now pour (slowly!) some of the ice-cold alcohol carefully down the inside of the glass, allowing it to settle on top of the solution. DNA is insoluble in cold alcohol and while there will be a few bubbles, the other compounds in the mixture will dissolve, and the DNA will separate from the other ingredients. Leave it for about two to three minutes for this to happen
5. If you are lucky you will see a spindly white substance, maybe clumps of it if you are really careful, forming on top of the salt/detergent mixture. Be patient - it will happen slowly. The resulting 'goo' is unique to you; it is your very own DNA!

For more information visit:

http://www.h2g2.com/approved_entry/A26560424

Or watch Professor Brian Cox in action below.

http://www.bbc.co.uk/programmes/p01466mm