Thursday 21 January 2010

Help on: Installing an Analytical Balance


Do you have any problems relating to analytical chemistry for pharmaceuticals or training? Send your questions to the MTS helpdesk using our contact form.

"Recently I have ordered a new analytical balance for my lab. I want to know what precautions I will have to take for proper installation. And as for calibration, up to what range of weights should I verify?”

“The instructions supplied with a new analytical balance are usually quite comprehensive and provide information on how to set up the balance correctly taking into account suitable location and internal calibration capabilities. Some other considerations (as provided by Scientech Balances) are as follows:

  • Set up the balance on a firm weighing table and even surface. Turn the adjustable feet until the balance is level using the spirit level/bubble indicator as guidance.
  • Avoid exposing the balance to vibrations during weighing. Corners of rooms are usually less prone to vibrations.
  • Best operating temperature is about 20°C/68°F at about 50% relative humidity. If you transfer the balance to a warmer area, make sure to condition the balance for about 2 hours at room temperature, leaving the unit unplugged from AC power. This is because the moisture in the air can condense on the surfaces of a cold balance whenever it is brought into a substantially warmer place. Never expose the balance to extreme moisture over long periods.
  • Protect the balance from drafts that come from open windows or doors. Heat and air-conditioning ducts will also product draft resulting in unstable readings.
  • Use caution when using weigh containers made of plastic since plastic is more prone to holding a electrostatic charge. If the samples being weighed hold static electricity an aftermarket static ionizer maybe needed for ionization for static removal. Static charges tend to develop when different materials rub against one another. Some materials can pick up excess electrons, resulting in negative static charges while other materials give up electrons, resulting in a positive charge. If the charged material is non-conducting (as are films, glass lenses and plastics), then the static charge remains.
  • Allow sufficient space around the balance for ease of operation and keep away from radiating heat sources.

Modern analytical balances typically include internal calibration features but regularly checking the accuracy against external calibrated masses is good practice. The calibration weights which you should verify will depend on the operating range of the balance so choose weights which bracket the range of weights which you will use the balance to measure and perhaps one or two spaced out throughout the range."

Wednesday 20 January 2010

Help on: Troubleshooting in pharmaceutical analysis


Do you have any problems relating to analytical chemistry for pharmaceuticals or training? Send your questions to the MTS helpdesk using our contact form.

"What are the general problems occurring in HPLC, GC and spectroscopy during operation in the pharmaceutical industry?”

“A full discussion of the general problems which can occur when operating HPLC, GC and spectroscopy for applications in the pharmaceutical industry could run to several books! In my experience the greatest problems are usually due to a lack of experience, knowledge and skills on the part of the operator (that’s probably the answer you would expect from a trainer!).

Modern analytical instruments have developed to such an extent that they can be fairly simple to use, with sophisticated software that lulls you into a false sense of security about your own abilities. It pays to remember what is actually happening during analysis and a good background in the theory of the technique will enable effective troubleshooting.

If you consider HPLC, setting up a run and then processing it can be quite a straightforward task. But, if the results are not as expected then a solid understanding of the method will help to assess the available information and diagnose the problem. This knowledge extends to an understanding of how the instrumentation works, an example being the selection and use of a suitable wash solvent to prevent carryover of your analyte from one injection to another. Most often, problems will occur when developing methods for new compounds, since that is when knowledge and skills are tested most.

The answer to building suitable skills and knowledge is primarily through effective training (which Mourne Training Services is always happy to provide) but developing experience after the training is equally important. Making sure that learning is fully implemented and kept up to date is a significant challenge for both individuals and managers in the pharma industry. Troubleshooting problems actually helps to develop expertise.

There is a wealth of information to be found on the web relating to troubleshooting of all these techniques. For example, type ‘HPLC troubleshooting’ into a search engine and you will be presented with numerous helpful resources. I recommend chromatography magazines such as LCGC which has regular troubleshooting columns for both LC and GC. There are also many books available which provide more in-depth knowledge regarding troubleshooting.”

Tuesday 19 January 2010

MTS Website Updates

The MTS website has been updated!

You can now access more information about our new online training package for in-house use: UTrain. This includes a request form for a free trial of the package to allow you to try it out.

We have also updated the free training resources page including a Useful Links section. Please send us your suggestions for links.