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Welch Chromatographic Solutions for Peptide Drugs
Chromatographic analysis for peptide drugs are important for ensuring product quality and safety. In this article, we introduce our solutions for peptide drug analysis, including the chiral analysis of protected amino acids, the determination of peptide related substances, the analysis of peptide aggregates by SEC, and the evaluation of amino acid ratios using the Welch Ultisil Amino Acid Method Kit. -
[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. -
On World Chocolate Day: Analyzing Disodium EDTA in Chocolate by HPLC
Chocolate is one of the most consumed sweet on Earth, and its quality and safety is a major consideration. However, chocolate's component greatly interfere with chromatographic analysis. In this article, we present an HPLC method with trichloromethane pretreatment to analyze Disodium EDTA in chocolate. -
Welch Solution for Biological Sample Analysis
In this article, we present solutions for the chromatographic analysis of biological samples from Welch Materials, covering SEC, RPLC, HIC, and ion exchange chromatography, with multiple applications of peptides, nucleic acids, antibodies, and proteins. -
[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. -
WelPacker DAC: Your Best Teammate in Purification
Dynamic Axial Compression (DAC) columns are a definitive tool in preparative-scale liquid chromatographic separation and purification. In this article, we thoroughly explore the key advantages of WelPacker DAC and discover its packing and maintenance details. -
[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. -
Advanced Chromatographic Resolution of Chiral Compounds, Part VI: Intermediates
While synthetic intermediates are not themselves in the final API, their stereochemical purity affects product quality greatly. In this article, we present application notes of five typical synthetic intermediates, witnessing how Blossmate chiral columns successfully separate them from their enantiomers. -
Maximizing Longevity: Five Practical Ways to Extend HPLC Column Life
An HPLC column is a high-cost core consumable in laboratories, and improper handling and operational errors contribute to column degration. In this article, we introduce five foundational rules that safeguard your HPLC columns and explain the reason behind it.