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![[Readers Insight] Why Do Substances with Similar Polarity Dissolve in Each Other?](//www.welch-us.com/cdn/shop/articles/dissolve_535x.jpg?v=1773724307)
![[Readers Insight] Why Do Substances with Similar Polarity Dissolve in Each Other?](//www.welch-us.com/cdn/shop/articles/dissolve_345x345@2x.jpg?v=1773724307)
[Readers Insight] Why Do Substances with Similar Polarity Dissolve in Each Other?
In this article and attached video, the author discusses why substances with similar polarity dissolve in each other through dipole-dipole interactions, the energy change during dissolution, and the effect from entropy and Gibbs free energy. -
![[Readers Insight] HPLC Column Selection: Core to Method Development (Part II)](//www.welch-us.com/cdn/shop/articles/1080-1105-2_535x.jpg?v=1773724204)
![[Readers Insight] HPLC Column Selection: Core to Method Development (Part II)](//www.welch-us.com/cdn/shop/articles/1080-1105-2_345x345@2x.jpg?v=1773724204)
[Readers Insight] HPLC Column Selection: Core to Method Development (Part II)
In this article, the author shares their answers for 8 common questions in column selection, aiming to guide users in choosing the most suitable column through practical experimentation. -
![[Readers Insight] HPLC Column Selection: Core to Method Development (Part I)](//www.welch-us.com/cdn/shop/articles/columnselection2-1080-1105_535x.jpg?v=1773724222)
![[Readers Insight] HPLC Column Selection: Core to Method Development (Part I)](//www.welch-us.com/cdn/shop/articles/columnselection2-1080-1105_345x345@2x.jpg?v=1773724222)
[Readers Insight] HPLC Column Selection: Core to Method Development (Part I)
A chromatographic column is the heart of separation. However, with thousands of column options on the market, it is often asked how to choose "the best one". In this article, the author explains the classifications of HPLC columns and how to select the most cmpatible column for an analyte. -
![[Readers Insight] Why Do Ghost Peaks Appear?](//www.welch-us.com/cdn/shop/articles/ghost-peak-1080-1029_97b7ea33-b337-4ee9-a749-66252df7cf0b_535x.jpg?v=1773724186)
![[Readers Insight] Why Do Ghost Peaks Appear?](//www.welch-us.com/cdn/shop/articles/ghost-peak-1080-1029_97b7ea33-b337-4ee9-a749-66252df7cf0b_345x345@2x.jpg?v=1773724186)
[Readers Insight] Why Do Ghost Peaks Appear?
In this article, we examine the common origins of ghost peaks in HPLC. From mobile phase contamination and instrument residues, to column impurities and sample-related degradation, the article explains how they contribute to the appearance of ghost peaks. -
![[Readers Insight] Is Retention Time Determined Solely by the Polarity of a Compound?](//www.welch-us.com/cdn/shop/articles/ret-time-1080-1027_535x.jpg?v=1773724051)
![[Readers Insight] Is Retention Time Determined Solely by the Polarity of a Compound?](//www.welch-us.com/cdn/shop/articles/ret-time-1080-1027_345x345@2x.jpg?v=1773724051)
[Readers Insight] Is Retention Time Determined Solely by the Polarity of a Compound?
Have you ever thought about this question: In reversed-phase chromatography, does an earlier elution always mean the compound has higher polarity? Or rather — is retention time determined solely by the polarity of a compound? In this article, we explore what polarity is, why it acts as the primary factor affecting retention time, and what other factors are unneglectable. -
![[Readers Insight] Mobile Phase Selection in Method Development: How to Optimize](//www.welch-us.com/cdn/shop/articles/mpoptimize-1080-1020_535x.jpg?v=1773723983)
![[Readers Insight] Mobile Phase Selection in Method Development: How to Optimize](//www.welch-us.com/cdn/shop/articles/mpoptimize-1080-1020_345x345@2x.jpg?v=1773723983)
[Readers Insight] Mobile Phase Selection in Method Development: How to Optimize
In method development, the selection of mobile phases is an important part to success. This article discusses thoroughly different mobile phases and their use in HPLC and LC-MS, and provides recommendations for initial mobile phase choices. -
Распространенные проблемы при твердофазной экстракции: практическое руководство по устранению неполадок
Solid-Phase Extrtaction is a fast, easy and high-performance sample preparation technique widely used, but routine SPE runs can encounter recurring problems. This article summarizes typical causes and practical fixes for each SPE problem. -
![[Readers Insight] Retention Time Drifts: Why Do They Occur?](//www.welch-us.com/cdn/shop/articles/1080-1017-2_535x.jpg?v=1773718683)
![[Readers Insight] Retention Time Drifts: Why Do They Occur?](//www.welch-us.com/cdn/shop/articles/1080-1017-2_345x345@2x.jpg?v=1773718683)
[Readers Insight] Retention Time Drifts: Why Do They Occur?
Learn the causes of retention time drift in HPLC analyses, explained thoroughly through mobile phase, column, instrument, and sample solvent. -
Устранение слабого удерживания и множественных помех при анализе метабисульфита натрия методом ВЭЖХ
В этой статье рассматривается метод ВЭЖХ для точного определения метабисульфита натрия в сложных рецептурах, где обычные добавки, такие как лимонная кислота, бензоат натрия и динатриевый ЭДТА, могут создавать помехи. Благодаря использованию колонки Welch Xtimate Sugar-H достигается надежное удержание сахара и эффективное разделение без помех. -
Спаситель диабета: человеческий инсулин и метод его анализа ВЭЖХ
В этой статье представлено практическое исследование ВЭЖХ-анализа человеческого инсулина с использованием колонки Welch Xtimate? SEC-120, демонстрирующее стабильную и надежную работу колонки при количественном определении инъекций человеческого инсулина. -
Главный алкалоид: никотин и стратегия разработки метода его определения
Анализ никотина, как известно, представляет собой сложную задачу из-за его слабого удерживания на обычных колонках. В данной статье представлен практический метод УВЭЖХ-МС с использованием колонки Welch Ultisil HILIC Amphion II, а также подробно описан подход к разработке, условия хроматографирования и ключевые преимущества для надежного обнаружения никотина. -
![[Readers Insight] Matrix Effects in Mass Spectrometry: Why They Matter](//www.welch-us.com/cdn/shop/articles/matrix-effect-2-1080-922_535x.jpg?v=1773718626)
![[Взгляд читателей] Матричные эффекты в масс-спектрометрии: почему они важны](//www.welch-us.com/cdn/shop/articles/matrix-effect-2-1080-922_345x345@2x.jpg?v=1773718626)
[Взгляд читателей] Матричные эффекты в масс-спектрометрии: почему они важны
В этой статье мы более подробно рассмотрим, как матричные эффекты влияют на результаты восстановления в масс-спектрометрических анализах, препятствуя потере препарата, и обсуждаем, когда их следует корректировать с помощью калибровочных кривых, подготовленных с использованием пустых матриц.
![[Readers Insight] Why Do Substances with Similar Polarity Dissolve in Each Other?](http://www.welch-us.com/cdn/shop/articles/dissolve_535x.jpg?v=1773724307)
![[Readers Insight] Why Do Substances with Similar Polarity Dissolve in Each Other?](http://www.welch-us.com/cdn/shop/articles/dissolve_345x345@2x.jpg?v=1773724307)
![[Readers Insight] HPLC Column Selection: Core to Method Development (Part II)](http://www.welch-us.com/cdn/shop/articles/1080-1105-2_535x.jpg?v=1773724204)
![[Readers Insight] HPLC Column Selection: Core to Method Development (Part II)](http://www.welch-us.com/cdn/shop/articles/1080-1105-2_345x345@2x.jpg?v=1773724204)
![[Readers Insight] HPLC Column Selection: Core to Method Development (Part I)](http://www.welch-us.com/cdn/shop/articles/columnselection2-1080-1105_535x.jpg?v=1773724222)
![[Readers Insight] HPLC Column Selection: Core to Method Development (Part I)](http://www.welch-us.com/cdn/shop/articles/columnselection2-1080-1105_345x345@2x.jpg?v=1773724222)
![[Readers Insight] Why Do Ghost Peaks Appear?](http://www.welch-us.com/cdn/shop/articles/ghost-peak-1080-1029_97b7ea33-b337-4ee9-a749-66252df7cf0b_535x.jpg?v=1773724186)
![[Readers Insight] Why Do Ghost Peaks Appear?](http://www.welch-us.com/cdn/shop/articles/ghost-peak-1080-1029_97b7ea33-b337-4ee9-a749-66252df7cf0b_345x345@2x.jpg?v=1773724186)
![[Readers Insight] Is Retention Time Determined Solely by the Polarity of a Compound?](http://www.welch-us.com/cdn/shop/articles/ret-time-1080-1027_535x.jpg?v=1773724051)
![[Readers Insight] Is Retention Time Determined Solely by the Polarity of a Compound?](http://www.welch-us.com/cdn/shop/articles/ret-time-1080-1027_345x345@2x.jpg?v=1773724051)
![[Readers Insight] Mobile Phase Selection in Method Development: How to Optimize](http://www.welch-us.com/cdn/shop/articles/mpoptimize-1080-1020_535x.jpg?v=1773723983)
![[Readers Insight] Mobile Phase Selection in Method Development: How to Optimize](http://www.welch-us.com/cdn/shop/articles/mpoptimize-1080-1020_345x345@2x.jpg?v=1773723983)
![[Readers Insight] Retention Time Drifts: Why Do They Occur?](http://www.welch-us.com/cdn/shop/articles/1080-1017-2_535x.jpg?v=1773718683)
![[Readers Insight] Retention Time Drifts: Why Do They Occur?](http://www.welch-us.com/cdn/shop/articles/1080-1017-2_345x345@2x.jpg?v=1773718683)
![[Readers Insight] Matrix Effects in Mass Spectrometry: Why They Matter](http://www.welch-us.com/cdn/shop/articles/matrix-effect-2-1080-922_535x.jpg?v=1773718626)
![[Взгляд читателей] Матричные эффекты в масс-спектрометрии: почему они важны](http://www.welch-us.com/cdn/shop/articles/matrix-effect-2-1080-922_345x345@2x.jpg?v=1773718626)