What the analyst expects from you

What the analyst expects from you…

A simplified schematic of the DI water process.

Laboratory water

From a laboratory scientist point of view, the water we drink it is dirty. In a laboratory we need get our water closer to the school ideal of H2O (pure water).

LOD from signal-to-noise ratio

How low can you go? A practical guide to the Limit of Detection

Before you chose a piece of equipment or experimental method you need to ensure that it can detect the thing you want to measure (analyte) in the concentrations present. For example, can your method detect 1ppb phosphate in sea water? If you can’t measure it then there is no point in making, or collecting, it!

Excel and statistics for physical scientists

While Excel is anything but ideal for use in statistical work it can do many amazing things. However, it can be quite opaque as to what is actually happening and difficult to find the correct function. For this reason I have picked out the key functions for the statistical analysis discussed here.

Choosing a SignificanceTest.

Significance tests

In an experiment you may hypothesize there is a relationship between two values or two sets of values. To ensure that relationship is robust you need carry out a test of the significance of that hypothesized relationship.

The analytical balance.

The laboratory balance: a practical guide

The laboratory balance is so often the forgotten object that sits in the corner of the laboratory. Forgotten, that is, until it is called on to give an accurate measurement. There are few things more frustrating than a balance that is not behaving itself and usually this is due to neglect.

The forward method of operating a mechanical pipette.

Practical pipetting: a guide

The overlap between cooking and science is massive. So, when I heard the key ability of a chef being described as: “Perfect and fast. Fast and perfect” it rang some bells; particularly for the time consuming laboratory process of transferring liquids. We may use different words such as “accurate and precise” but the principle is the same. Get it wrong and your experiment may be ruined, take too long and you’ll be there forever.

Going Green – Solvents

In Cohen labs we have been looking at ways of decreasing our environmental impact and improving safety for our lab users. One aspect of this is looking at our use of non-aqueous solvents.