Knowledge Base
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How to Calculate Spiked Recovery Rate in Chromatographic Analysis
In analytical chemistry, spiked recovery rate is a fundamental parameter used to evaluate the accuracy of an analytical method. In this article, we explore the three categories of spiked recovery experiments, the calculation of spiked recovery rate and required spiking amount, and the practical experimental guidelines for a valid experiment. -
[Readers Insight] Is Elution Order Determined Solely by the Polarity of a Compound?
In introductory liquid chromatography training, almost every beginner has heard the following statement: “In reversed-phase chromatography, more polar compounds elute first, while less polar compounds elute later.” But chromatography is not that simple. In this article, we discuss factors beyond polarity that determines elution order. -
Transferring HPLC Methods to UHPLC: Here's How
In modern analytical chemistry, UHPLC offers significant benefits, including increased throughput, superior resolution, and reduced solvent consumption. However, transferring methods from HPLC to UHPLC is more than simply swapping columns. In this article, we explore the essentials in transferring a method, from mathematical calculation to method validation. -
What Is UHPLC? Understanding the Differences Between UHPLC and HPLC
HPLC has been one of the most widely used analytical chromatographic techniques, yet it is not fast enough to meet every laboratory analysis. In this article, we explore UHPLC, the faster version of liquid chromatography, compare the differences between UHPLC and HPLC, and discuss the limitations and application fields of UHPLC. -
[Readers Insight] Does Hydrogen Bonding Exist between Acetonitrile and Water?
The existence of hydrogen bonding in acetonitrile-water solutions is a fundamental question. In this article, we will discuss the question in details, including the physicochemical properties of acetonitrile and water, the interaction that takes place when acetonitrile is dissolved in water, and the abnormalities that may occur when using acetonitrile-water solutions as mobile phase or for sample extraction. -
[Readers Insight] Why Mobile Phase Alterations Can Reverse Elution Order
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. -
When LC Methods Failed to Reproduce: What Could Be the Cause?
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. -
Solvent Effect, The Hidden Killer of Chromatographic Peak Shapes
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. -
[Readers Insight] What Happens If Formic Acid Was Replaced by Acetic Acid in HPLC Analysis?
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. -
[Readers Insight] A Novel Analytical Approach: New Perspectives on Ionic Liquid Extraction
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. -
Dedicate or Share? Maximize Your HPLC Column Use
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. -
[Readers Insight] Why Peak Fronting Occurs? Causes and Analysis
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.