Dec 21, 2023 17:10
5 mos ago
25 viewers *
English term
replicate standard
English to Russian
Tech/Engineering
Chemistry; Chem Sci/Eng
Chromatography
High Performance Liquid Chromatography
Linearity
Linearity was demonstrated through the analysis of replicate standards at six levels ranging in concentration from 1.0 mg/mL to 2.0 mg/mL.
Calibration data and the corresponding calibration curve are contained in Appendix.
Linearity
Linearity was demonstrated through the analysis of replicate standards at six levels ranging in concentration from 1.0 mg/mL to 2.0 mg/mL.
Calibration data and the corresponding calibration curve are contained in Appendix.
Proposed translations
+1
9 hrs
*
Declined
измерение (разведений) стандартного раствора в нескольких повторностях
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&c...
Следует использовать, по меньшей
мере, 6 градуировочных стандартов в не менее чем двух повторностях.
Линейность, точность
36–48 проб (6 уровней концентрации, 6–8 повторных анализов на каждом уровне, кроме того,
20 образцов для анализа помех)
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Note added at 9 hrs (2023-12-22 02:51:55 GMT)
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https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&c...
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Note added at 9 hrs (2023-12-22 02:53:45 GMT)
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Не та ссылка на второй фрагмент, надо
https://www.unodc.org/documents/scientific/validation-R.pdf
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Note added at 21 hrs (2023-12-22 14:38:48 GMT)
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Все вопросы - к автору оригинала
https://www.shimadzu.eu/sites/shimadzu.seg/files/shimadzu_ap...
Calibration over the target concentration range is linear on both
detectors, and precision is demonstrated below 2%
for analysis of six replicate standards at the
concentration range of interest
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Note added at 21 hrs (2023-12-22 15:06:07 GMT)
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https://www.jsmcentral.org/sm-chromatography/fulltext_acst-v...
Three replicate standards per concentration level were prepared
and processed. Three measurements of each extract were performed
on the UHPLC System. The linearity range covers sub-therapeutic,
therapeutic and supra-therapeutic (toxic) levels
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&c...
Следует использовать, по меньшей
мере, 6 градуировочных стандартов в не менее чем двух повторностях.
Линейность, точность
36–48 проб (6 уровней концентрации, 6–8 повторных анализов на каждом уровне, кроме того,
20 образцов для анализа помех)
--------------------------------------------------
Note added at 9 hrs (2023-12-22 02:51:55 GMT)
--------------------------------------------------
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&c...
--------------------------------------------------
Note added at 9 hrs (2023-12-22 02:53:45 GMT)
--------------------------------------------------
Не та ссылка на второй фрагмент, надо
https://www.unodc.org/documents/scientific/validation-R.pdf
--------------------------------------------------
Note added at 21 hrs (2023-12-22 14:38:48 GMT)
--------------------------------------------------
Все вопросы - к автору оригинала
https://www.shimadzu.eu/sites/shimadzu.seg/files/shimadzu_ap...
Calibration over the target concentration range is linear on both
detectors, and precision is demonstrated below 2%
for analysis of six replicate standards at the
concentration range of interest
--------------------------------------------------
Note added at 21 hrs (2023-12-22 15:06:07 GMT)
--------------------------------------------------
https://www.jsmcentral.org/sm-chromatography/fulltext_acst-v...
Three replicate standards per concentration level were prepared
and processed. Three measurements of each extract were performed
on the UHPLC System. The linearity range covers sub-therapeutic,
therapeutic and supra-therapeutic (toxic) levels
Reference comments
1 day 17 hrs
Igor Andreev
Native in Russian
Native in: Russian 
Works in: English to Russian, Ukrainian to Russian, English to Ukrainian
Related KudoZ points
:
195
Reference:
Replicates in Analytical Methods - When and How Many?
Do you prepare your samples/standards in duplicate without really thinking about it? If challenged on why, would your answer be something like, "it's good practice, isn't it?" The use of replicates in analytical procedures is commonplace but it is important to understand why you are doing it and also what the results are telling you.
There are different types of replicates in analytical methods, which are used for different purposes. Most commonly it comes down to two types, either preparation replicates or measurement replicates. In the case of preparation, these are samples or standards that are prepared from the beginning to end of the procedure in the same way but separately (often referred to as replicate weighings). In the case of measurement replicates, a single sample/standard is measured more than once (an example would be multiple injections in the case of HPLC).
Standard Preparation
Replicates in calibration standard preparation are often used to provide confidence in the initial weighing of the standard material. The idea is that if the response is corrected using the actual amount which was weighed out, then the response factors will be the same if the weighing has been performed correctly.
This may apply in the case of single point calibrations, where a single concentration of standard is used for the calibration, or in multi-level calibration where the original weighing is diluted to prepare a series of standards over a range of concentrations.
The difficult part is setting an acceptance criteria for the required agreement between these replicate standards. Duplicate preparation is common since it requires the least amount of extra work but two results cannot be compared using common statistical tools, such standard deviation. Usually the agreement is expressed as a percentage of one result compared to the other. How close this should be to 100% will depend on the inherent error in the method and the considerations are similar to those in setting acceptance criteria during method validation.
...
There are different types of replicates in analytical methods, which are used for different purposes. Most commonly it comes down to two types, either preparation replicates or measurement replicates. In the case of preparation, these are samples or standards that are prepared from the beginning to end of the procedure in the same way but separately (often referred to as replicate weighings). In the case of measurement replicates, a single sample/standard is measured more than once (an example would be multiple injections in the case of HPLC).
Standard Preparation
Replicates in calibration standard preparation are often used to provide confidence in the initial weighing of the standard material. The idea is that if the response is corrected using the actual amount which was weighed out, then the response factors will be the same if the weighing has been performed correctly.
This may apply in the case of single point calibrations, where a single concentration of standard is used for the calibration, or in multi-level calibration where the original weighing is diluted to prepare a series of standards over a range of concentrations.
The difficult part is setting an acceptance criteria for the required agreement between these replicate standards. Duplicate preparation is common since it requires the least amount of extra work but two results cannot be compared using common statistical tools, such standard deviation. Usually the agreement is expressed as a percentage of one result compared to the other. How close this should be to 100% will depend on the inherent error in the method and the considerations are similar to those in setting acceptance criteria during method validation.
...
Discussion
Т.е., если вы, как в случае System Suitability, будете вкалывать при прогоне образцов по 5-6 повторов 5-6 стандартов для каждых 6-10 образцов, вы просто угорите. Т.е., для выполнения линейности методику несколько меняют и делают 5-6 вводов 1 стандарта (например, самой низкой концентрации). А вот что делали авторы представленного фрагмента я, увы, понять не могу. Читать можно и справа налево, и слева направо, и по диагонали, и вообще как вздумается. По любому нужно смотреть Приложение, чтобы оценить их "креативность". Другой момент - авторство. Сейчас этих креативных такое количество из самых разных мест, что, как говорила тетя Роза Дальвадорес " и не сосчитаешь". Поэтому этот фактор тоже необходимо принимать в рассмотрение, чтобы понять на какое число делить представленный текст. Единица здесь вряд ли уместна.
Мораль: и разведения, и повторности - равновероятны, как и шанс встретить/не встретить мамонта до момента ознакомления с Приложением.
https://www.usp.org/sites/default/files/usp/document/harmoni...
Но в ней четко прописано replicate injections, а вот у разных авторов уже начинаются всевозможные инсинуации, смысл коих иногда просто так не разберешь. Еще один момент есть duplicate standard. Это не повторный ввод стандарта, это т.н. эталон-свидетель или вторичный эталон, приготовленный по образу и подобию первичного эталона. В общем, это "скользкая" тема. Еще один момент глава <621> USP написана по поводу пригодности хроматографической системы, а не по ее линейности. Хотя рекомендации по количеству повторностей автоматом переносятся на линейность. .Обычно вкалывают 5-6 повторов стандарта в начале прогона и в качестве bracketing standards через каждые 6-10 образцов.
P.S. Six levels - это и есть 6 разведений: 1,... , и 2 mg/mL, т.е. в этом двукратном диапазоне изменения концентраций. Какие еще 4 концентрации были использованы, должно быть указано в методике