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Knowledge Base

[Readers Insight] Why Mobile Phase Alterations Can Reverse Elution Order

July 1, 2026

Poor resolution is challenging, but elution order reversal is even perplexing. In this article, the author discusses three primary factors that cause peaks to elute inversed when mobile phase changes: pH, organic modifier, and buffer salt.

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When LC Methods Failed to Reproduce: What Could Be the Cause?

June 28, 2026

Reproducibility issues are an unavoidable topic in HPLC. In this article, we break down easily overlooked, application-level factors that cause reproducibility failures into four aspects: reagents, samples, instruments, and columns, and provide a practical troubleshooting framework to help chromatographers isolate issues and achieve robust, consistent separation results in daily laboratory practice.

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Solvent Effect, The Hidden Killer of Chromatographic Peak Shapes

June 25, 2026

Unexplained peak fronting and split peaks often compromise HPLC data quality. Among all possible culprits, solvent effect is the one often overlooked. This article explores the mechanisms of this hidden killer and provides actionable strategies to restore peak symmetry.

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[Readers Insight] What Happens If Formic Acid Was Replaced by Acetic Acid in HPLC Analysis?

June 18, 2026

In this article, we discuss the catastrophic results one would get if they replace formic acid in the mobile phase by acetic acid in an HPLC experiment.

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[Readers Insight] A Novel Analytical Approach: New Perspectives on Ionic Liquid Extraction

June 16, 2026

In this article, we explore a novel analytical approach utilizing the ionic liquid [EimHSO4] for copper ion extraction. By examining its unique phase separation and coordination mechanisms, it highlights how this innovative methodology could pave the way for future LC-MS sample preparation and quantification.

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Dedicate or Share? Maximize Your HPLC Column Use

May 11, 2026

In laboratory analysis, it is common to encounter scenarios where a column loses efficacy after being used in a different project, or where dozens of projects must be conducted by a small amount of columns. In this article, we explore the balance of dedicated and shared HPLC column use to ensure reliable analytical results while maximizing available resources.

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[Readers Insight] Why Peak Fronting Occurs? Causes and Analysis

April 14, 2026

Peak fronting is a common chromatographic anomaly characterized by a gradual leading edge and a steep trailing edge, often occurring during method development. This phenomenon stems from multiple causes, thus resolving it can be much more difficult. In this article, we discuss three primary sources of peak fronting and provide technical solutions to mitigate these effects and optimize chromatographic performance.

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[Readers Insight] When to Use Acetone as a Mobile Phase?

April 12, 2026

Acetone is a versatile solvent in chromatography, yet its application as an HPLC mobile phase remains limited to specific cases like Sudan dye analysis. This article explores the reasons behind the rare use of acetone and summarizes the key considerations when using acetone as a mobile phase.

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[Readers Insight] Why Does the PDA Detector Remain a Cornerstone of Analytical Laboratories

March 30, 2026

We all know that Mass Spectrometry is preferable for trace analysis due to its superior sensitivity. But why do PDA detectors still maintain a high utilization rate? In this article, we explore the practical advantages PDA holds compared to MS.

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The Selectivity Among Detectors: Why Mass Spectrometry Surpasses Spectroscopy?

March 26, 2026

Selectivity is a definitive factor in analytical chemistry. In this article, we discuss the differences between optical spectra and mass spectra, and explain why mass spectrometry surpasses spectroscopy in selectivity.

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[Readers Insight] Is "Not Detected" Truly "Not Detected"? (Not An Article about LOD)

March 19, 2026

When you encounter "Not Detected" in analytical chemistry, does it truly mean the substance is absent? In practice, unscrupulous manufacturers may try to evade detection of prohibited additives by modifying molecular structures to something out of the detection scope. In this article, the author introduces a method using TOF-IDA/MS to effectively expose such modification without the need of reference standards.

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[Readers Insight] How to Analyze Fragment Ions in Mass Spectrometry?

January 19, 2026

In this article, we investigate the fundamental mechanisms of ion fragmentation within mass spectrometry workflows and explore why systematically mapping fragment-ion structures is essential for deeper mass-spectrometric interpretation. It explores the relationship between electronic displacement and dissociation pathways, emphasizing structural reconstruction over simple pattern recognition.

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