InstantForum.NET v4.1.4PerkinElmer Discussion Forumhttp://forums.perkinelmer.com/techsupport@perkinelmer.comSun, 23 Nov 2008 06:37:14 GMT20http://forums.perkinelmer.com/Topic208-7-1.aspxWith regards to mixing samples with the LSC, how much mixing is required for optimal counting conditions?<br><br> My protocol is to add 5ml aqueous sample (containing [sup]3[/sup]H-inositols in 5% TCA solution) to 10ml Insta-gel plus scintillation cocktail and vortex until the mixture goes from cloudy to clear, or for about 1min if mixture doesnt clear. <br><br>Lately Ive found that after counting the samples overnight, the next morning samples would have two distinct layers. A bottom, white very viscous layer and a top, clear layer. Does anyone know what could cause this and whether it affects the amount of counts detected in the samples? (I get much higher, 10x the usual, background levels in these experiments and am unsure if its related to sample mixing)Tue, 30 Sep 2008 21:27:01 GMTErinhttp://forums.perkinelmer.com/Topic181-7-1.aspxProposed Swipe Assay Kit would include:</P><P>1 Liter of ULTIMA Gold XR</P><P>200 7ml Glass Vials</P><P>1 pack of 100 Filter Paper</P><P>Application NoteTue, 22 Jul 2008 07:31:30 GMTMChttp://forums.perkinelmer.com/Topic177-7-1.aspxIs it possible to count Ethanol samples in MicroScint O or Betaplate Scint?Fri, 11 Jul 2008 08:45:50 GMTMShttp://forums.perkinelmer.com/Topic168-7-1.aspxI would like to determine 14C in sea water samples. Typical sample quantities are 5 ml sea water, which vary in pH from 2 to 8. Currently we have Ultima Gold LLT available at our company. Is it possible to use Ultima Gold LLT and is additional sample preparation necessary for sea water samples?Wed, 02 Jul 2008 09:54:24 GMTMShttp://forums.perkinelmer.com/Topic155-7-1.aspxThe RadioAnalysis group in my company is transitioning away from Oxidizing blood samples. We're attempting various methods of solubilizing the samples using Solvable. <P>Currently our procedure, based on an approximate aliquot weight of 0.2g, is as follows:</P><P>Add ~1mL Solvable</P><P>Incubate at ~60ºC for at least 1 hour</P><P>Allow to cool to room temperature</P><P>Add ~0.1mL 0.1M EDTA</P><P>Add ~0.5mL H2O2</P><P>Allow foaming to subside (at least overnight)</P><P>Add ~10mL Ultima Gold XR </P><P>The "problem" we're experiencing is high luminescence values in our samples with low counts (predose aliquots, for instance)... naturally, due to the presence of the H2O2. </P><P>For example:</P><P>DPM= 58 | CPMA= 11 | tSIE= 207.43 | LUM= 29</P><P>This occurs for both 3H and 14C samples. </P><P>I have 2 questions regarding the values:</P><P>1] Do the high luminescence values affect the figures we're seeing in our DPM and CPMA values (we're using TriCarb 2900's running on QuantaSmart, WITH luminescence correction installed)?</P><P>2] Will those luminescence values decrease if our samples are incubated after the H2O2 addition? </P><P>Regarding #1, my supervisor is convinced the DPM and CPMA values are entirely inaccurate if the luminescence values are high.</P><P>Thanks in advance for your thoughts!</P><P>M.KüehlThu, 05 Jun 2008 13:19:09 GMTMKuehlhttp://forums.perkinelmer.com/Topic147-7-1.aspxI heart at a recent show that PerkinElmer was launching a new Ultima Gold product. Has anyone else heart of this - I didn´t see anything on their website? - Thanks"Tue, 13 May 2008 09:44:20 GMTRonhttp://forums.perkinelmer.com/Topic130-7-1.aspxI am running polyacrylamide gels and silver staining them to identify my radiolabeled (tritium) protein of interest, then cutting out the band, dissolving it in "Solvable", and counting it in a scintillation counter. I have read some references which suggest that silver staining will quench the tritium signal. Has anybody tried this?<br>Thanks!!Tue, 15 Apr 2008 16:22:59 GMTgaryhttp://forums.perkinelmer.com/Topic125-7-1.aspxI want to count vacuum pump oil that maybe contaminated with tritium. How do I do it. What is the best cocktail to use.Mon, 31 Mar 2008 08:47:11 GMTSoxFanhttp://forums.perkinelmer.com/Topic126-7-1.aspxHi,</P><P>In order to miniaturizing LSC assay, it is recommended to use cocktails with high sample loading capacities in microplate format. For TopCount, MicroScint PS is recommend. For MicroBeta Ultima Gold XR is recommended. Does anyone know why different cocktails are recommended for these two instruments?Thu, 03 Apr 2008 06:20:22 GMTalberhttp://forums.perkinelmer.com/Topic123-7-1.aspxAnnexample of increasing counts was observed when glass fiber filters were quantified in a Safe LSC cocktail. Previously applied methods in a classical cocktail were adapted to a Safe cocktail.</P><P>The observed phenomenon of incresing counts can be explained by the higher viscosity of a Safe cocktail.</P><P>It just takes more time to elute the sample from a filter compared to a classical cocktail and when counting is stared at a too early stage, material can come of the filter and contribute to increasing count rates over a period of time until an equilibrium is reached.Tue, 18 Mar 2008 04:38:08 GMTJtWhttp://forums.perkinelmer.com/Topic119-7-1.aspxHow can LSC samples be decolorized?Fri, 14 Mar 2008 16:43:24 GMTAquasolichttp://forums.perkinelmer.com/Topic50-7-1.aspxI have a high number of LSC samples per day. Does Perkin provide "giant" formats of my cocktail (UltimaGold) with a reduced cost per liter?:cool:Thu, 06 Mar 2008 10:07:15 GMTEShttp://forums.perkinelmer.com/Topic117-7-1.aspxIs there a guide that shows what cocktails are compatible with what microplates?<P>:DThu, 13 Mar 2008 13:49:42 GMTThe Terminatorhttp://forums.perkinelmer.com/Topic32-7-1.aspxWhat exactly is the difference between Safer and Classical products?Thu, 03 Jan 2008 12:37:02 GMTMChttp://forums.perkinelmer.com/Topic34-7-1.aspxWhat is sample load capacity and why should this be considered before setting up my assay?Thu, 03 Jan 2008 12:50:51 GMTMC