Knowledge Base
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[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)
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?
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?
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
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. -
Common Problems in Solid-Phase Extraction: A Practical Troubleshooting Guide
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?
Learn the causes of retention time drift in HPLC analyses, explained thoroughly through mobile phase, column, instrument, and sample solvent. -
Resolving Weak Retention and Multiple Interferences in the HPLC Analysis of Sodium Metabisulfite
This article discusses an HPLC method for accurately determining sodium metabisulfite in complex formulations where common additives such as citric acid, sodium benzoate, and disodium EDTA may cause interference. By using Welch Xtimate Sugar-H column, the method achieves strong retention and effective separation without interferences. -
The Savior of Diabetes: Human Insulin and Its HPLC Analysis Method
This article presents an HPLC case study on the analysis of human insulin using the Welch Xtimate® SEC-120 column, featuring the column’s stable and reliable performance in quantifying human insulin injections. -
A Premier Alkaloid: Nicotine and the Strategy for Developing Its Determination Method
Nicotine analysis is notoriously challenging due to its weak retention on conventional columns. This article shares a practical UHPLC-MS method using the Welch Ultisil HILIC Amphion II column, detailing the development approach, chromatographic conditions, and key advantages for reliable nicotine detection. -
[Readers Insight] Matrix Effects in Mass Spectrometry: Why They Matter
In this article, we explore further how matrix effects affects recovery results in mass spectrometry analyses by hindering preparation loss, and discuss when it should be corrected by using calibration curves prepared by blank matrices. -
Determination of Mannitol Related Substances with Xtimate Sugar-Ca
Mannitol is a substance with important applications in pharmaceutical and food. See how Welch Xtimate Sugar-Ca columns perform well in determination of mannitol related substances in accordance with Chinese Pharmacopoeia 2025 Edition.