Which UV-spectrophotometer ?

[gozde]

Hi,

I would ask if you would buy a Perkin Elmer, or PG Inst UV-visible spectrophotometer?

I used Perkin Elmer previously, and is very accurate as I know. I had some difficulties with the sipper and software but they were minor problems. Now I would like to ask his/her opinion to someone who has used both instruments.

Thanks,

Gozde

[DR]

It really depends on your application.
For our routine dissolution samples, we found a Thermo Evolution 220 to be effective (and lots cheaper than high end units from PE and Cary). It also has the benefit of using a Xe flash lamp - it is only on when it is needed, no warm up time, no crazed optics due to long term exposure to UV, no D2 lamps having to be replaced annually or every other year whether used or not...

But for high end sensitivity at narrower slit widths, reduced stray light etc, the larger, more expensive UVs with longer light paths are still better.

PS - you might have a look around to see if spectroscopists have their own forum similar to this, you would probably get a lot more detailed information elsewhere.

[gozde]

That helped a lot. Thanks.

[uzman]

Hi Gozde ,

PG Instruments has some drawbacks , such as blue straylight filter inside the instrument becoming foggy during time course , and effecting the readings around 500nm.
Also the 8 cell compartment producing back emf voltages during position change and changing the absorbance readings during measurements on certain cell positions , especially on position 2.
The UV-Win software is good and user friendly but take into consideration of those mechanical problems.

[gozde]

Thanks uzman. I think I want Cary 60.
And price of PG has already made me suspicious about future problems, even if you did not mention them.

PS for doctor, Thermo is not cheaper at all in Turkey