Erol
☆    

Turkey,
2019-04-09 13:51
(1814 d 22:12 ago)

Posting: # 20135
Views: 7,656
 

 Storage conditions of plasma samples [Bioanalytics]

Hello everyone,

What should be the freezer storage intervals for plasma to be stored at -20°C. Our freezer's range is between -15°C and -40°C. We have a question for this. Question is upper limit is high and it must be maximum -25°C. Is anyone can give me information for the stability of plasma samples -40°C is wrong and why? Thanks.

Dr. Erol
Ohlbe
★★★

France,
2019-04-10 12:25
(1813 d 23:38 ago)

@ Erol
Posting: # 20136
Views: 7,002
 

 Storage conditions of plasma samples

Dear Erol,

❝ What should be the freezer storage intervals for plasma to be stored at -20°C. Our freezer's range is between -15°C and -40°C. We have a question for this. Question is upper limit is high and it must be maximum -25°C.


I guess you mean the lower limit, giving a range of -25°C to -15°C ?

❝ Is anyone can give me information for the stability of plasma samples -40°C is wrong and why?


Generally speaking, if your analyte is stable at -20°C it will be also stable at -40°C. The EMA guideline allows a bracketing approach for small molecules (i.e. if you demonstrate stability at -70°C and -20°C it will cover all temperatures in between). The FDA 2018 guidance goes farther and states that stability at -20°C would cover colder temperatures. The draft M10 guideline allows extrapolation to lower temperatures only for small molecules but allows bracketing for large molecules. This still remains from the Crystal City 3 discussions and White Paper (hey, this one used to be free and now seems to be only accessible for a fee ?). I've heard since at a number of bioanalytical conferences that there is no published data to back up this distinction between small and large molecules. My understanding from discussions at the 13th WRIB last week is that industry will try and have it removed from the M10 final guidance.

Oh, by the way: I doubt your -20°C freezer would be able to reach -40°C anyway.

Regards
Ohlbe
Helmut
★★★
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Vienna, Austria,
2019-04-10 12:46
(1813 d 23:17 ago)

@ Ohlbe
Posting: # 20137
Views: 6,962
 

 OT: Free access to the AAPS J

Dear Ohlbe,

❝ […] the Crystal City 3 discussions and White Paper (hey, this one used to be free and now seems to be only accessible for a fee ?).


Articles of the AAPS J are available for free about one year after publication via PubMed Central. In this case you see the summary and a link to the PDF.
Interesting that articles of Pharm Res (the other main journal of the AAPS) are not free.

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Ohlbe
★★★

France,
2019-04-10 13:45
(1813 d 22:18 ago)

@ Helmut
Posting: # 20138
Views: 6,976
 

 OT: Free access to the AAPS J

Dear Helmut,

❝ Articles of the AAPS J are available for free about one year after publication via PubMed Central. In this case you see the summary and a link to the PDF.


Thanks. I did things the wrong way 'round: I had the paper on my computer, went to the journal from it to provide a link, instead of searching Medline.

So these guys at Springer charge you if you want to download the paper from their own website, but grant others a right to provide it for free... Hum. Not sure I fully understand all marketing strategies.

Regards
Ohlbe
nobody
nothing

2019-04-10 14:26
(1813 d 21:38 ago)

@ Helmut
Posting: # 20139
Views: 6,911
 

 OT: Free access to the AAPS J

❝ Interesting that articles of Pharm Res (the other main journal of the AAPS) are not free.


I always considered AAPS J as yellow press, but found out recently that in the meantime it has a higher impact factor than Pharm Res... (while the Springer subscription is half the price compared to Pharm Res).

PS: Where do these stars under my "nobody" suddenly come from? Very disturbing...

Kindest regards, nobody
Helmut
★★★
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Vienna, Austria,
2019-04-10 17:26
(1813 d 18:37 ago)

@ nobody
Posting: # 20141
Views: 6,865
 

 Forum internal: ★

Hi nobody,

❝ […] in the meantime it has a higher impact factor than Pharm Res... (while the Springer subscription is half the price compared to Pharm Res).


The cheapest way is to become a member of AAPS. Then the subscription for both is included and you have access to ancient stuff not available at PMC.

❝ PS: Where do these stars under my "nobody" suddenly come from?


See FAQ#20.
Before it stated “Junior, Regular, Senior, etc.” in dark red (I know you preferred pink). I had to update this “status” manually in the database and received a couple of e-mails like “Why am I still a Junior; I made already 26 posts!”… Hence, I modified the scripts to query the database and throw these stars.

❝ Very disturbing...


I thought that stars and their color are less obtrusive than the text. I’m sorry that they disturb you.
If you insist I can introduce an exception for you. What do you prefer? ♥ ☠ ☢ ☣ ⚕ ℞ or nothing (which would match your nick)?

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nobody
nothing

2019-04-10 17:42
(1813 d 18:21 ago)

@ Helmut
Posting: # 20142
Views: 6,873
 

 Forum internal: ★

I left behind my US clubs last year. No money going in this direction these days, sorry.

I would prefer "nothing" (all lower case, in pink, of course). Possible?

Kindest regards, nobody
Helmut
★★★
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Vienna, Austria,
2019-04-10 17:57
(1813 d 18:06 ago)

@ nobody
Posting: # 20143
Views: 6,831
 

 Forum internal: ★

Hi nobody,

❝ I would prefer "nothing" (all lower case, in pink, of course). Possible?


Your wish is my command. I opted for hotpink (#FF69B4) cause I think it fits you better. If you want boring pink (#FFC0CB), let me know.

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[image]

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nobody
nothing

2019-04-10 18:10
(1813 d 17:53 ago)

@ Helmut
Posting: # 20145
Views: 6,806
 

 Forum internal: ★

Pörfect! Many thanks!

Kindest regards, nobody
Helmut
★★★
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Homepage
Vienna, Austria,
2019-04-10 18:17
(1813 d 17:46 ago)

@ nobody
Posting: # 20147
Views: 6,816
 

 Forum internal: ★

Hi nobody,

❝ Pörfect! Many thanks!


Welcome. Shall I add this one

[image]

as your avatar?

Dif-tor heh smusma 🖖🏼 Довге життя Україна! [image]
Helmut Schütz
[image]

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nobody
nothing

2019-04-10 18:33
(1813 d 17:30 ago)

@ Helmut
Posting: # 20148
Views: 6,809
 

 Forum internal: ★

...better not. I don't want to raise any suspicion. Things are complicated these days. You might end up as a terror organization if you do some art work.

Kindest regards, nobody
mittyri
★★  

Russia,
2019-04-10 18:02
(1813 d 18:01 ago)

@ Helmut
Posting: # 20144
Views: 6,835
 

 Unique statuses

Hi Helmut,

❝ I had to update this “status” manually in the database and received a couple of e-mails like “Why am I still a Junior; I made already 26 posts!”… Hence, I modified the scripts to query the database and throw these stars.


❝ If you insist I can introduce an exception for you. What do you prefer? ♥ ☠ ☢ ☣ ⚕ ℞ or nothing (which would match your nick)?


Hey, are you ready for a next wave of mails with suggestions to have 'unique' statuses?

Kind regards,
Mittyri
Helmut
★★★
avatar
Homepage
Vienna, Austria,
2019-04-10 18:16
(1813 d 17:47 ago)

@ mittyri
Posting: # 20146
Views: 6,812
 

 Unique statuses

Hi mittyri,

❝ Hey, are you ready for a next wave of mails with suggestions to have 'unique' statuses?


The moment I uploaded the script to the server the same idea came into my mind. I hope not.

Dif-tor heh smusma 🖖🏼 Довге життя Україна! [image]
Helmut Schütz
[image]

The quality of responses received is directly proportional to the quality of the question asked. 🚮
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nobody
nothing

2019-04-12 12:43
(1811 d 23:21 ago)

@ Helmut
Posting: # 20152
Views: 6,558
 

 Unique statuses

...you can always say you did nothing for nobody, so no precedence at all ;)

Kindest regards, nobody
Erol
☆    

Turkey,
2019-04-10 22:29
(1813 d 13:34 ago)

@ Ohlbe
Posting: # 20149
Views: 6,798
 

 Storage conditions of plasma samples

Dear Ohlbe,
Thank you for your answer.

Regards

Erol


Edit: Full quote removed. Please delete everything from the text of the original poster which is not necessary in understanding your answer; see also this post #5[Helmut]
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