Why L-ascorbic acid has yellow color when dissolved in water?

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What solvent can I used for Paal Knorr reaction between 6-amino hexanoic acid and 2.5 hexanedione?

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Ester cleavage conditions?

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Is CD44 degraded in lysosome together with hyaluronan after CD44 mediated endocytosis of hyaluronic acid?

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How to remove DCU and HOBT from my reaction?

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What is the most common number of epitopes in an multi-epitope Vaccine?

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I want to performe MALDI-TOF MS for bacterial identification, I would appreciate it if anyone can tell me the matrix solution preparation protocol ?

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Unknown debris sheets observed in cell culture flasks?

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How to increase solubility of Poly acrylic acid in Dioxane solvent?

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What is a good reagent for lentiviral plasmid transfection in HeLa cells?

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Steingrimur Stefansson

Hi Estriningtyas Rismawanti . It sounds like you have oxidation of the ascorbic acid. I would reccommend making a concentrated stock solution of ascorbic acid in high quality DI water and keep it in the cold.

Yurii V Geletii

Dear Steingrimur Stefansson , you are right. Solutions of ascorbic acid become yellow due to oxidation by air. Use each time a freshly prepared stock solution.