Lactic acid quantitation in hand dishwashing liquid using an HILIC-UV methodology.
Different hydrophilic interaction chromatography (HILIC) columns were screened for lactic acid separation in hand dishwashing liquid products and the influence of mobile phase strength, buffer concentration and column temperature on the retention of lactic acid on a Zorbax NH(2) column was investigated. An isocratic HILIC method for the quantitation of lactic acid in hand dishwashing liquid products was developed. The mobile phase consists of 70% methanol and 30% 20 mM sodium phosphate buffer (v/v) at pH 2.5. The HILIC stationary phase is Zorbax NH(2), 250x4.6 with a 5 microm particle size. Detection was carried out using a variable wavelength UV-VIS detector at 226 nm. The linear range and percent recovery for lactic acid in the products were 44.68-1206.39 microg/mL and 100.3%, respectively. This paper provides an optimized HILIC methodology for the analysis of an acidic polar analyte (lactic acid) on a basic stationary phase. The proposed method can be used for the routine analysis of lactic acid.
Storton
Mark
M
Global Analytical Science Department, Colgate-Palmolive Company, Piscataway, NJ 08855, USA.
Exarchakis
James
J
Waters
Tracy
T
Hao
Zhigang
Z
Parker
Barry
B
Knapp
Michael
M
D002021:Buffers; D002853:Chromatography, Liquid / Q000379:methods*; D006235:Hand Disinfection; D019344:Lactic Acid / Q000032:analysis*; D057230:Limit of Detection; D015203:Reproducibility of Results; D013056:Spectrophotometry, Ultraviolet / Q000379:methods*; D013501:Surface-Active Agents / Q000737:chemistry*; D013696:Temperature
D002021:Buffers; D013501:Surface-Active Agents; D019344:Lactic Acid