How was 2009 for you? What do you need to work on in 2010?

LEARNING AT WORK
Training know-how applied to laboratory science

Now that 2009 is coming to an end it is a good time to review how your professional year went and consider what you want to do next year. This may be performed as part of a companywide performance review programme where you will use proscribed templates to identify what you have achieved and what your targets will be for next year. All too often these procedures can feel like a paperwork exercise which is simply done so that a tick can be put in the right box. However, if you want to develop your career further it is a good idea to use a performance review as an opportunity to assess what you can do well and where you want to be in the future.

A training plan is a key component in developing your skills. If you do not have support for formal training then you need to find ways to learn about your chosen subject in an informal way. I am going to concentrate on the technical skills related to working in a pharmaceuticals analytical laboratory but you can probably apply a similar approach to the other workplace skills you require such as so called ‘soft skills’, which includes communication, time management, people management, project planning etc.

What do you currently do well? To figure out what you want to improve you first need to assess your current knowledge and skills. In a laboratory setting this will usually translate into knowledge and skills related to particular analytical tasks. Write out all the tasks which you have used over the past year and try to determine your level of proficiency. It may be convenient to use the following categories:

Analytical chemistry laboratory skills & knowledge
Examples include: Using a balance; Using volumetric glassware; pH measurement; Analytical method validation; Analytical method transfer,etc.

Laboratory techniques
Examples include: High Performance Liquid Chromatography (HPLC); Infra-red spectroscopy; Water determination by Karl Fischer; Titrations, etc.

Laboratory procedures
Examples include: Use of laboratory documentation; Knowledge of standard operating procedures (SOPs); Recording data; Equipment calibration; Deviations and out of specification results, etc.

Pharmaceutical science
Examples include: Forced degradation studies; Stability studies, etc.

This is quite a difficult task. It is advisable to seek help from others. This may mean talking to your line manager but it may also help to talk to an experienced colleague or your peers to give you a range of opinions. You may encounter bias if you only seek out one person’s opinion. The aim is not to come out as high as possible for each identified task but to determine your level of competency as accurately as possible. At the same time as discussing what your current level is you also need to figure out what you need to do next and prioritise which tasks are likely to be most important in your day to day work and most beneficial to furthering your career. The next stage is to convert the information you have obtained into a realistic training plan for 2010.

If you discover that you already have a broad range of knowledge and skills at a highly proficient level (you probably already knew this but it’s nice to have it confirmed!) then you may wish to develop an area of expertise. This is a great way to raise your profile.

Two things to consider:

1. Pick a topic which you find interesting and if possible, very interesting. It is much easier to develop expertise in a subject area that you are passionate about.
2. Pick a subject in which you have a realistic opportunity to gain experience and which is a valuable asset in your career plans.

To summarise, figure out what you are able to do well and what you need to be able to do well to move on to the next step on your career ladder.

This advice is based on the approach used by Mourne Training Services for performing training needs analysis. We carry out job analysis for the roles in your laboratory and define competence based standards for the work activities identified. We then assess current capabilities and identify the learning needs for which training solutions are suggested. Contact us if you are interested in our training consultancy services for training needs analysis.

Feedback from free HPLC training video

In June of this year Mourne Training Services released a free training video on YouTube: ‘A Brief Guide to HPLC instruments’. The video has been extremely popular with over 9000 views in the last six months from all around the world. It has a 5 star rating and has been selected as a favourite by YouTube users many times. An example of a particularly gratifying comment is this one: ‘great video; thank you very much for a simple to understand component breakdown of the process!’ This type of comment assures us that we have achieved our aim with this video.

It was intended to provide a useful resource which explained how all the bits in a HPLC system come together to enable HPLC analysis but it was also an opportunity to try out our new concept for online training. Stretching our minds back to university days we remembered that being at a lecture and having something explained to you was much better in terms of retaining the information than trying to make sense of the notes later, even if the notes were very good. A one hour lecture could take as much as 3 or more hours to get to grips with on your own. We tested this theory a little further by using a poll on the MTS blog where we asked:

Which of the following two methods of learning do you prefer?
1. Reading well written notes on the topic
2. Watching a video which explains the topic

The response was overwhelmingly for option 2; watching a video. Hardly scientific research but still adding to the overall theory that having something explained to you verbally is preferable, even without opportunities for questions.

Our new online training solution, UTrain, consists of training videos which are similar to ‘A Brief Guide to HPLC instruments’ but contain further information. The videos are supported by exercises which can be undertaken by an individual or as part of a group. Fully completed solutions for these exercises is provided. The training is finished off with an e-learning review/assessment which tests the learning. On successful completion of the assessment a certificate is awarded which is recognised by the Royal Society of Chemistry for the purposes of continuing professional development.

UTrain is available as a subscription service which can be purchased by your laboratory. It consists of a series of modules which are available separately, thus you can choose the training that is needed in your lab. The first four modules are available now on the topic of basic HPLC.

Contact us for more information, or, if you would like to arrange a free trial of UTrain so that you can try it out for yourself.

HPLC calculator for pressure conversion

PEAK SOLUTIONS A resource for chromatographers Last month we gave away a HPLC calculator for working out column equilibration times. This month we are pleased to announce that the calculator has been updated to include converting pressure values into different units. Click here to access the calculator; it will open as an Excel document. The directions for how to use the calculator are provided on the spreadsheet.

Help on: Difference in retention times using Agilent and Waters HPLC systems

MTS HELPDESK

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

Question:
"I have a question... I want to know why there is a difference in the retention times observed when using Agilent systems and Waters systems?”

Answer:
“To answer this question we must first look closely at what exactly is a retention time? It is measured as the time from the injection of the sample to the time the separated component of interest is observed by the HPLC detector. Therefore the total retention time will depend not only on the time taken for the component to travel through the HPLC column but also the time taken to travel through the tubing both before the column and after the column. This time, which is in addition to that spent on the column, will depend on the overall volume of tubing, we refer to this as the ‘extra column volume’.

The amount of extra column volume for different brands of HPLC instruments will be slightly different since they are not all made in the same way. Additionally, the user of the instrument can alter the extra column volume by a variety of actions such as replacing lengths of tubing, cutting off the end of the tubing when removing stainless steel ferrules, installing column switching valves, etc. These factors result in small differences in the retention time observed for different brands of instrumentation.

A feature of the chromatogram which tells us about the extent of the extra column volume is the void volume, t0. This is usually the first disturbance in the baseline and corresponds to the solvent in which your sample was injected. This solvent is unretained and so corresponds to the time required for an unretained component to travel through the column to the detector. If you calculate the capacity factor, k’ you can remove the effects of extra column volume for each peak, this value should be the same for different HPLC systems (assuming all other variables are constant, i.e. same column, same mobile phase, same method etc.).

Capacity factor, k’ = (t – t0)/t0

where t = retention time and t0 = the time taken for non-retained components to elute. The capacity factor is a measure of where the peak of interest is located with respect to the void volume (the elution time of unretained components).

Another reason for a difference in retention times which can lead to larger differences relates to gradient methods. When running these types of method the changes in mobile phase composition are controlled by the gradient proportioning valve (GPV) in the pump (for low pressure mixing HPLC systems, the most common type in use). The consequence of this is that there is a delay between changing the gradient and that effect being experienced at the column. This has to take into account the extra volume between the GPV and the injection port. The total volume from the GPV to the column is called the dwell volume and this is another reason why you may experience different retention times using Instruments from different manufacturers. In my experience I have noticed very little difference when measuring the dwell volumes of Agilent and Waters systems.

To calculate the dwell volume for a particular system, refer to a previous post on interpretation of HPLC methods (Wednesday, 14th October 2009).

In practice we tolerate small differences in retention time on different systems provided there is no negative effect on the observed chromatography but a larger difference may need further investigation.”

Do you have anything to add? Feel free to leave a comment.

Thoughts on applying QbD to analytical methods

The MTS blog post on applying Quality by Design to analytical methods (Wednesday 11th November 2009) has been published as a short article on the Pharma QbD website.

Quality by Design for analytical methods

ANALYTICAL TOPICS

Quality by Design (QbD) is the name given to the principle of fully understanding a process and the effect of the various characteristics which influence the process, rather than just testing the resulting product at the end to check if the process has performed as expected. This concept was adopted by the FDA in 2004 as detailed in ‘Pharmaceutical CGMPs for the 21st century – A Risk Based Approach’ [1] and is included in ICH Q8 'Pharmaceutical Development’ [2] and ICH Q9 ‘Quality Risk Management’ [3].

QbD has been applied to manufacturing processes but can it be applied to analytical methods? When we develop analytical methods we typically select suitable method parameters based on experience and knowledge and then check to ensure that we can achieve the desired results by applying analytical method validation characteristics. Thus we can ensure that the method can quantify at the levels required, that the results are always the same and that they give the true value, etc. This approach does not result in a full understanding of how the parameters of the method can affect the results.

Validation guidelines such as ICH Q2 [4] list the validation characteristics which should be investigated when validating your analytical method. These characteristics include intermediate precision, reproducibility and robustness. These three can provide understanding of the effects of method parameters.

Intermediate precision tests how the method performs when carried out by different analysts, on different analytical systems, on different days, etc. Reproducibility is required when the method needs to transferred to another laboratory and adds to the previous variables investigated for intermediate precision that of carrying out the method in a different laboratory. Robustness testing investigates the effect of slight changes to the method parameters. For example, in a HPLC method the effect of the flow rate, buffer strength and composition of the mobile phase might be investigated.

If performed thoroughly and correctly, the combination of these three validation characteristics can provide a good understanding of how a method performs and yet often this is not the case. Why?

One of the problems is that these characteristics are usually investigated at the end of a validation study due to the effort involved; they are time consuming, require different analysts, systems etc and thus are expensive to perform. For this reason they may only ever be investigated for projects which are in a late stage of development and even then often only the bare minimum of testing is performed. Also, there is a tendency to treat validation studies as a ‘tick-list’ exercise. It is regarded as a separate task which may even be performed by a different set of operators to those routinely using the method, thus valuable knowledge and experience is not gathered together. Another issue is the statistical knowledge required to interpret the results, particularly relating to robustness studies which are best performed using multivariate analysis techniques, such as design of experiments (DoE).

Applying QbD would involve moving these studies which provide an understanding of the method to the beginning of the method development process instead of performing them at the end of method validation. This would mean that the method parameters would be chosen on the basis of these experiments and would be within a design space of the method. The use of automation in these experiments would be desirable to reduce the effort involved and analytical chemists would benefit from a good understanding of the necessary statistics.


References:
1. US Food and Drug Administration, Pharmaceutical CGMPs for the 21st Century – A Risk Based Approach, 2004.
2. The International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use, Quality Guideline Q8 Pharmaceutical development, 2006.
3. The International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use, Quality Guideline Q9 Quality Risk Management, 2006.
4. The International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use, Quality Guideline Q2(R1) Validation of Analytical procedures: Text and Methodology, 2005.