Simplified Determination of Rutin in Anti-Aging Skin Cream Formulations

Stephan Altmaier, Lab Head Instrumental Analytics R&D and Anita Piper, Scientist Instrumental Analytics R&D

Rutin, also known as rutoside, quercetin-3-O-rutinoside, or sophorin, is a quercetin glycoside found in various plants, including buckwheat and asparagus. The chemical structure contain units of Rutoside and the disaccharide rutinose (α-L-rhamnopyranosyl-(1->6)-β-Dglucopyranose).

Rutin is believed to possess antioxidant properties, and/or posses anti aging effects on human dermal fibroblasts and human skin. Like other bioflavonoids, Rutin is investigated for its biological activity and often formulated as skin cream, i.e. semi-solid emulsions of oil and water, products.

HPLC analysis of skin cream formulations can profit from use of monolithic rods over particle based columns, due to higher tolerance against matrix-rich samples and clogging. This application illustrates how Rutin can be determined in skin cream samples using a monolithic Chromolith® HighResolution RP-18 endcapped column with UV detection. Sample preparation of the cream samples would only require ethanol-solubilization and filtration prior to analysis, lowering both the cost and time of analysis.

 

Experimental Conditions
Column Chromolith® HighResolution RP-18e 100x4.6 mm
Injection volume 1 µL
Flow rate 1 mL/min
Temperature 25 °C
Pressure drop 56 - 85 bar (812-1233 psi)
Detection VWD, 5 Hz, Response Time 0.1 s, UV = 220 nm
Mobile phase A Phosphate buffer (10 mM, pH 3)
Mobile phase B Methanol
Gradient Time (min) A (%) B (%)
  0 55 45
  5 55 45
  10 10 90
  10.1 55 45
  15 45 45
Diluent Ethanol
Standard solution Rutin was accurately weighed and diluted to volume with diluent (282 µg/mL).
Sample preparation 50 mg Day-Cream were weighed into a 25 mL volumetric flask and filled up with ethanol. The cream suspension was placed into an ultra sonic bath for 20 minutes.

The sample solution was filtered through a 0.45 μm PTFE filter directly into the HPLC vial prior to analysis and placed in the autosampler.

 

Standard Solution

Chromatographic Data Standard Solution (282 µg/mL)

No. Compound Retention Time (min) Area (mAU*min) Tailing Factor
1 t0 void volume 2.0    
2 Rutin 2.8 2,266 1.2

 

Cream samples

1. Selectivity: Inject standard solution of Rutin and determine the retention time, peak purity, tailing factor and column efficiency

No. Retention Time (min) Plates (USP) Tailing Factor Peak Purity
1 Rutin 2.8 8004 1.2 1.000

2. LOD & LOQ

Concentration (ppm)  
LOD (ppm)   5.5
LOQ (ppm) 16.7

3. Linearity (area mAU*min)

Concentration (ppm) Mean Area
2,820  0.06
7,050 0.13
14,100 0.26
28,200 0.50
56,400 1.17
141,000 2.86
282,000 5.77

 

 

Materials