ArticleInternational journal of molecular sciences2020
Improved HPLC Conditions to Determine Eumelanin and Pheomelanin Contents in Biological Samples Using an Ion Pair Reagent.
Article in International journal of molecular sciences, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 22 papers.
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Who cites it
22 citing papers in PubMed, 40 citations in OpenAlex.
- Restoring brain functions in the Mo-blo mouse model of Menkes disease with copper nanoclusters.Science advances · 2026Article
- Unraveling UVA1-Induced Photomodifications of Eumelanin and Pheomelanin in Human Skin: Insights into Pigment Darkening.International journal of molecular sciences · 2026Article
- Photoreactive Properties of Melanin Obtained from Human Induced Pluripotent Stem Cell-Derived Melanocytes.International journal of molecular sciences · 2025Article
- Two-pore channel 2 is required for soluble adenylyl cyclase-dependent regulation of melanosomal pH and melanin synthesis.Pigment cell & melanoma research · 2024Article
- Melanometry for objective evaluation of skin pigmentation in pulse oximetry studies.Communications medicine · 2024Review
- Resveratrol-Enriched Rice Callus Extract Inhibits Oxidative and Cellular Melanogenic Activities in Melan-A Cells.Antioxidants (Basel, Switzerland) · 2024Article
- Exploring the Influence of Cold Plasma on Epidermal Melanogenesis In Situ and In Vitro.International journal of molecular sciences · 2024Article
- Eumelanin Detection in Melanized Focal Changes but Not in Red Focal Changes on Atlantic Salmon (International journal of molecular sciences · 2023Article
- Taphonomic experiments reveal authentic molecular signals for fossil melanins and verify preservation of phaeomelanin in fossils.Nature communications · 2023Article
- Distinct cAMP Signaling Microdomains Differentially Regulate Melanosomal pH and Pigmentation.The Journal of investigative dermatology · 2023Article
- Melanin biopolymers from microbial world with future perspectives-a review.Archives of microbiology · 2023Review
- Inhibitory Effects of Polyphenol- and Flavonoid-Enriched Rice Seed Extract on Melanogenesis in Melan-a Cells via MAPK Signaling-Mediated MITF Downregulation.International journal of molecular sciences · 2023Article
- Recent Advances in Characterization of Melanin Pigments in Biological Samples.International journal of molecular sciences · 2023Review
- Genetic architecture and evolution of color variation in American black bears.Current biology : CB · 2023Article
- Effects of Aging on Hair Color, Melanosomes, and Melanin Composition in Japanese Males and Their Sex Differences.International journal of molecular sciences · 2022Article
- 5,6-Dihydroxyindole eumelanin content in human skin with varying degrees of constitutive pigmentation.Pigment cell & melanoma research · 2022Article
- Differential Induction of Reactive Oxygen Species and Expression of Antioxidant Enzymes in Human Melanocytes Correlate with Melanin Content: Implications on the Response to Solar UV and Melanoma Susceptibility.Antioxidants (Basel, Switzerland) · 2022Article
- Natural Melanin: Current Trends, and Future Approaches, with Especial Reference to Microbial Source.Polymers · 2022Review
- Chemical and biochemical control of skin pigmentation with special emphasis on mixed melanogenesis.Pigment cell & melanoma research · 2021Review
- Photoreactivity of Hair Melanin from Different Skin Phototypes-Contribution of Melanin Subunits to the Pigments Photoreactive Properties.International journal of molecular sciences · 2021Article
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Authors and funding
4 authors at 2 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Alkaline hydrogen peroxide oxidation (AHPO) of eumelanin and pheomelanin, two major classes of melanin pigments, affords pyrrole-2,3,5-tricarboxylic acid (PTCA), pyrrole-2,3-dicarboxylic acid (PDCA) and pyrrole-2,3,4,5-tetracarboxylic acid (PTeCA) from eumelanin and thiazole-2,4,5-tricarboxylic acid (TTCA) and thiazole-4,5-dicarboxylic acid (TDCA) from pheomelanin. Quantification of these five markers by HPLC provides useful information on the quantity and structural diversity of melanins in various biological samples. HPLC analysis of these markers using the original method of 0.1 M potassium phosphate buffer (pH 2.1):methanol = 99:1 (85:15 for PTeCA) on a reversed-phase column had some problems, including the short lifetime of the column and, except for the major eumelanin marker PTCA, other markers were occasionally overlapped by interfering peaks in samples containing only trace levels of these markers. These problems can be overcome by the addition of an ion pair reagent for anions, such as tetra-
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