You really need to try running your samples on the two instruments to see which is most appropriate. Without more information on the application it is diffciult to be more precise. I work for Malvern Instruments and we would be more than happy to demonstrate the Mastersizer to you. ■

There are other alternatives than laser diffraction like systems using online image analysis. The advantage is you get shape information plus "you see is what you get"

you can have a look at our homepage ■

Thanks for your answer.

I did have a look at image analysis, but as this particle analyzer will be part of our QC procedure, laser diffraction is the best option for us, it's less time consuming and easier to use. John, I'm in touch with one of your colleague and will come to Malvern pretty soon to do some trials.

No offense to helpful salesman, but I was hoping more for some users experience on these machines, the pros and cons of their everyday uses...

Thanks ■

image analysis is not more time consuming : look e.g. at FPA or PartAn from Anatec. You fill your sample in, you start your measurement, product is fed computer controlled by vibrating feeder, goes throug a dispersing nozzle in case of fine material in the FPA and measurement results are continuously updated while the measurement is running, you get your printout and stored results in tables (plus images if you like).

So I see no difference in ease of use compared to LD

Best regards

Peter ■

Thanks a lot bill that's a lot of usefull information. I've just had a meeting with a salesman from Horiba, so I'm now looking also at the LA950V2.

I'm going to recheck the data of the different machines using your recomendation. It seems that the Crystalizer is an end of the line product not to say outdated, which explain probably the low cost compare to other. Unfortunately these machines don't come cheap and cost is definitely an issue here. The Malver seems to be the easy choice as it's the most used, but the problem with the 2000E is that it's not automated and with people with little experience like me, the less adjustement the better. The LA950V2 is fully automated and seems to have everything we're looking for...

I haven't heard of the Beckman Coulter LS 13320 before, I'm going to give them a call to see if they have a budget option for us.

Thanks for you offer of running sample for us but I've already sent sample to Malvern and Horiba, and await their results.

Thanks again for all these info. ■

In my experience, I have found the Symaptec laser diffraction system to be a very robust and versatile tool in sizing dry product, be it fine or coarse or mixed. Our group work primarily with fine pharmaceutical powders and we have recently purchased the Symaptec laser diffraction system.

The key reason for our choice was that being a modular system, the Sympatec provides a range of dry dispersion options. The trick with sizing dry products is dependent on how well the material is dispersed, and we have found the Sympatec dry dispersion capabilities far superior to that of other systems.

The Sympatec is able to disperse dry powders using different dispersion pressures, which also enables pressure titration studies. We have used pressure titration to not only develop methods for sizing, but also understand the cohesive/adhesive properties of different materials we work with. Furthermore, the different sampling options on the Symaptec enable measurements to be made using small quantities (30 - 40 mg), which is important when with working with drug actives. The Sympatec possesses two sampling units, which interface with the dry dispersion RODOS system. These include the VIBRI that employs a shoot and vibrating plate for which large quantities of powder may be sampled. The system that we use extensively is the ASPIROS, which disperses small quantities of powder enclosed in a small vial. These systems in-conjunction with the RODOS dispersing system have made method development a lot easier and sampling time a lot shorter.

The Symaptec laser diffraction housing - the HELOS comes with a range of lens, that enable sizing in the fine and coarse range. We have found that the ability of the Symaptec to collect data using both the Fraunhofer and Mie theory as another plus when we were reviewing it for purchase.

Working in an academic group, the modularity of the Sympatec one us over and we can now adapt the system to size material to our spec. Also, the support we have had from Sympatec has been fantastic, we find their servicing folk and after-sales support helpful. If you would like to have any further info on the system, please feel free to contact me on j.shur@bath.ac.uk. ■

One of the world most easest is the Microtrac particle size instrument.. ■

First I'd like to thank you all for your input. It's very useful to have other peoples opinion when we don't know much on the subject. We've now purchased our particle analyzer, and I thought I would share my experience for other people who might look for the same thing.

We were looking for a laser difraction particle analyzer that could do measurement in the range of 0.1 to 500 micron in dry.

We tried the Malvern 2000, the Horiba LA950-V2 and the Beckman Coulter LS 13 320. We've had to discard the LS 13 320 as the tornado dispersion system was not powerful enough to disperse properly our powder.

It's was then difficult to chose between the Malvern and the Horiba. Both machines performance were identical.

The Horiba has advantages in bench size and user friendliness of the software but their previous model were not always recommended by other users. Malvern is well established in the uk and promised to offer a better after sale service.

At the end we took the risk to go with Horiba, and after almost 6 month, we are very please of our choice.

Being novice in particle size analysis we needed a lot of help and support, and that's exactly what we got from Horiba.

They've always answered quickly and professionally to all our questions, and I would definitely recommend them to anyone looking at purchasing a particle analyzer.

Thanks again to all. ■