A critical analysis of single-frequency LCR databridge impedance measurements of human skin

Details

• Personal Author:
  Bunge AL ; Orazem ME ; White EA
• Description:
  Testing whether the barrier of skin samples has sufficient integrity for meaningful measurements of in-vitro chemical permeability is usually required when data are generated for regulatory purposes. Recently, skin integrity has been assessed using LCR databridge measurements, which are reported as resistances determined in either series (SER) or parallel (PAR) modes at a single frequency, typically 100 or 1000Hz. Measurements made at different combinations of mode and frequency are known to differ, although the skin literature reveals confusion over the meaning of these differences and the impact on the interpretation of integrity test results. Here, the theoretical meanings of resistance and capacitance measurements in PAR and SER mode are described and confirmed experimentally. SER-mode resistances are equal to the real part of the complex impedance; whereas, PAR-mode resistances are the inverse of the real part of the admittance. Capacitance measurements reported in SER and PAR modes are similar manipulations of the imaginary parts of the complex impedance and admittance. A large body of data from human cadaver skin is used to show that the PAR-mode resistance and SER-mode capacitance measured at 100Hz are sensitive to skin resistivity, which is the electrical measurement most closely related to skin integrity. [Description provided by NIOSH]
• Subjects:
  Men Occupational Health Safety Skin Skin Absorption Women
• Keywords:
  Author Keywords: Electrical Impedance Spectroscopy Constant Phase Element Humans In-vitro In-vitro-study Skin-absorption Skin-exposure Skin Barrier Function Skin Integrity Stratum Corneum
• ISSN:
  0887-2333
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  Colorado ; Florida ; OSHA Region 4 ; OSHA Region 8
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  25
• Issue:
  4
• NIOSHTIC Number:
  nn:20039405
• Citation:
  Toxicol In Vitro 2011 Jun; 25(4):774-784
• Contact Point Address:
  Annette L. Bunge, Chemical Engineering Department, Colorado School of Mines, Golden, CO 80401
• Federal Fiscal Year:
  2011
• Performing Organization:
  Colorado School of Mines
• Peer Reviewed:
  True
• Start Date:
  20040901
• Source Full Name:
  Toxicology in Vitro
• End Date:
  20090331
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:a07e776d8b402c5b4721b38ba61defd271f6cd4f54c7551f823023dc675eab77a29aa4b1039c5501db29453b68230d56744cf5768985b957f0999108a88b57b6
• Download URL:
  https://stacks.cdc.gov/view/cdc/192700/cdc_192700_DS1.pdf
• File Type:
  [PDF - 538.96 KB ]