Assessment of Regular and NPH Insulin Concentration via Two Methods of Quantification: The Washington State Insulin Concentration Study (WICS). Other Scholarly Work

Neumiller, Joshua J, Chen, Gang, Newsome, Cheyenne et al. (2021). Assessment of Regular and NPH Insulin Concentration via Two Methods of Quantification: The Washington State Insulin Concentration Study (WICS). . 15(2), 324-328. 10.1177/1932296819883291

cited authors

  • Neumiller, Joshua J; Chen, Gang; Newsome, Cheyenne; Hughes, Sally; Lazarus, Philip; White, John R

fiu authors

abstract

  • Background

    Recent reports have suggested that insulin vials purchased in community pharmacies do not meet the minimum required intact insulin concentration (≥95 U/mL) as defined by the United States Pharmacopeia. We sought to independently obtain multidose human insulin vials from a variety of community pharmacies across the state of Washington and quantitatively measure intact insulin.

    Methods

    Sixty 10-mL vials of insulin (n = 30 regular human insulin and n = 30 neutral protamine Hagedorn insulin) were purchased and assayed. To ensure random selection of lots and supply chain sources, insulin samples were purchased on a variety of calendar dates from various pharmacy locations across Washington State, inclusive of both chain and independent pharmacies. All samples were assessed for intact insulin concentration via both Ultra Performance Liquid Chromatography coupled with UV detection (UPLC-UV) and Ultra Performance Liquid Chromatography-Mass Spectrometry (UPLC-MS).

    Results

    When considering all samples (N = 60), the mean concentration was 101.8 ± 4.4and 91.5 ± 1.9 U/mL as determined by UPLC-UV and UPLC-MS, respectively. Measured concentrations ranged from 90.0 to 108.4 U/mL when assayed by UV UPLC and 86.1 to 95.4 U/mL for UPLC-MS.

    Conclusion

    To our knowledge, this is the first study following the report by Carter et al that assessed human insulin concentrations by both UPLC-UV and UPLC-MS. These findings are important because they demonstrate that the results obtained from these two methods differ and that the method used must be considered when interpreting findings.

publication date

  • March 1, 2021

keywords

  • Chromatography, High Pressure Liquid
  • Chromatography, Liquid
  • Humans
  • Insulin
  • Insulin, Isophane
  • Tandem Mass Spectrometry
  • Washington

Digital Object Identifier (DOI)

Medium

  • Print-Electronic

start page

  • 324

end page

  • 328

volume

  • 15

issue

  • 2