Allantoin

key words: Allantoin, CE, IUPAC: (2,5-Dioxo-4-imidazolidinyl), other names: urea5-ureidohydantoin,  glyoxyldiureide, CAS Number: 97-59-6, chemical formula: C4H6N4O3

The effectiveness of comfrey for the treatment of bone fractures and wound healing was already known to Hildegard von Bingen. The active ingredient is called allantoin.

Allantoin, allantoine, analysis of, Kapillarelektrophorese, CE, capillary electrophoresis

Structure of allantoin

Apart from comfrey allantoin is also found in other plants like black salsify and maple. Allantoin accellerates cell formation and soothes the skin. Besides the medical aspects allantoin became important in cosmetics and is therefore often found in skin creams, shower gels and suntan lotions. Nowadays mostly allantoin obtained by chemical synthesis is used. The analysis of allantoin with capillary electrophoresis is achieved using an electrolyte with acidic pH-value, where allantoin migrates as a cation. In the presence of complex sample matrices the use of micellar electrolytes is recommended.

Allantoin standard solution

  • Separation mode: MEKC
  • Electrolyte: Borate/SDS
  • Capillary: fused silica, 50 µm ID, bubble cell, 64 cm in total
  • Injection: 10 s, 50 mbar
  • Detection: direct UV, 225 nm
  • Description: The standard solution contains 20 mg/l allantoin.
Allantoin-Standard

Allantoin standard solution

Download: Allantoin-Standard.pdf

Linearity check of allantoin standard solutions

  • Separation mode: MEKC
  • Electrolyte: Borate/SDS
  • Capillary: fused silica, 50 µm ID, bubble cell, 64 cm in total
  • Injection: 10 s, 50 mbar
  • Detection: direct UV, 225 nm
  • Description: The linearity of allantoin has been investigated in the range of 1 to 1000 mg/l over eleven steps. The pdf shows the example of six electropherograms at different concentrations, the calibration line as well as statistical data of the calibration.
Allantoin-Lin-lang

Linearity of the determination of Allantoin

Download: Allantoin-Lin-lang

Allantoin in comfry

  • Separation mode: MEKC
  • Electrolyte: Borate/SDS
  • Capillary: fused silica, 50 µm ID, bubble cell, 64 cm in total
  • Injection: 10 s, 50 mbar
  • Detection: direct UV, 225 nm
  • Description: Allantoin is found in every part of comfry, whereas the roots are mostly used for medical purposes. The electropherograms summarized in the pdf show the analysis of watery extracts of the blossoms, leaves, stems and roots.
Allantoin in Beinwell

Allantoin in blossoms, stems, leaves and roots of comfry

Download: Allantoin-Beinwell.pdf

Allantoin in mouthwash and antidandruff lotion

  • Separation mode: MEKC
  • Electrolyte: Borate/SDS
  • Capillary: fused silica, 50 µm ID, bubble cell, 64 cm in total
  • Injection: 10 s, 50 mbar
  • Detection: direct UV, 225 nm
  • Description: The mouthwash and the antidandruff lotion were diluted with water. Further sample preparation was not necessary.
Allantoin-Mundwasser

Allantoin in mouthwash

Download: Allantoin-Mundwasser-Antischuppenlotion.pdf

Allantoin in shower gel and body-milk

  • Separation mode: MEKC
  • Electrolyte: Borate/SDS
  • Capillary: fused silica, 50 µm ID, bubble cell, 64 cm in total
  • Injection: 10 s, 50 mbar
  • Detection: direct UV, 225 nm
  •  Description: The shower gel and body-milk were diluted with water. Further sample preparation was not necessary.
Allantoin-Duschgel

Allantoin in shower gel

Download: Allantoin-Duschgel-Body-Milk

Calibration of allantoin with short-end method

  • Separation: MEKC, short-end
  • Electrolyte: Borate/SDS
  • Separation length: 8 cm
  • Capillary: fused silica, 50 µm ID, bubble cell, 64 cm in total
  • Injection: 5 s, -50 mbar from outlet side
  • Detection: direct UV, 225 nm
  • Description: Also for the short separation length of only 8 cm the quantification of allantoin is possible with very good linearity (R²=0,9999). The linearity has been investigated in the range of 1 to 1000 mg/l. The pdf shows the example of six electropherograms at different concentrations, the calibration line as well as statistical data of the calibration.
Allantoin-Lin

Linearity of allantoin standard solutions with a short separation distance

Download: Allantoin-Lin

Allantoin in medical creams

  • Separation: MEKC, short-end
  • Electrolyte: Borate/SDS
  • Capillary: fused silica, 50 µm ID, bubble cell, 64 cm in total
  • Injection: 5 s, -50 mbar from outlet side
  • Detection: direct UV, 225 nm
  • Description: Three different creams are shown which are used to support wound healing and prevention of scar forming, haemorrhoids and care cream for diabetic patients. Despite the very short separation length of 8 cm and the complex sample matrices all peaks were separated at the baseline. Allantoin was already detected after the short separation time of only one minute.
Allantoin-medizinische-Cremes

Allantoin in medical creams

Download: Allantoin-medizinische-Cremes

Allantoin in cosmetics

  • Separation: MEKC, short-end
  • Electrolyte: Borate-SDS
  • Capillary: fused silica, 50 µm ID, bubble cell, 64 cm in total
  • Injection: 5 s, -50 mbar from outlet side
  • Detection: direct UV, 225 nm
  • Description: Due to the skin smoothing and caring effect allantoin is inserted in multiple cosmetic products. Four different samples are shown where allantoin can easily be quantified despite different sample matrices.
Allantoin-Kosmetika

Allantoin in cosmetics

Download: Allantoin-Kosmetika