Human physiology utilizes electric fields for signaling, sensing and coordinating body functions. Every muscle movement is triggered by an electrical action potential speeding down neurons to stimulate muscle contraction. Every one of our senses uses ionic currents for signaling from the dark current in our retinal rods to the hair cells in the cochlea of the inner ear. The coordination of most of our organ systems utilizes electrical signals from heart contraction to the thought processing in our brain. So it should not be surprising that our largest organ, the skin, also uses electrical signals in its daily function to direct wound healing and send out distress signals indicating inflammation and skin cancer.

BioElectroMed has developed the Dermacorder™ bioelectric field imager for measuring the electric field in human skin. We have demonstrated its ability to measure electric fields associated with human skin wounds and skin lesions such as basal and squamous cell carcinoma. It can be used to monitor wound healing and to detect changes in the size of skin tumors.  This non-invasive instrument received an Investigational Device Exemption from two separate Institutional Review Boards for the human clinical trials but has not yet been approved for human use by the FDA. 

RECENT APPLICATIONS

Monitoring Wound Healing Non-Invasively

Mammalian skin has a transepidermal potential of about 20-50mV, inside positive. This voltage gradient across the skin is due to the unidirectional transport of the Na⁺ into and Cl^- out of the apical end of the epidermis, and K⁺ out of the basal end.

In addition to this polarized distribution of ion channels, the distribution of Na⁺/K⁺ ATPase ion pumps is also highly localized to the basolateral membranes. When a wound is made, a low resistance pathway is formed and the transepidermal potential goes to zero mV at the wound. However, at distances 1 mm away or greater, the transepidermal potential remains normal. This drives a current of injury out of the wound and generates a lateral electric field that can be detected non-invasively using the Dermacorder™.

5mm long wounds created in SKH-1 mice typically healed on day 6-7 post-wounding as shown in the figure above. At an indicated time point, the wound appearance, histology of the wound, and the surface potential scan by the Dermacorder™ are shown. On day 0 (d0), the full-thickness skin wound was made. The size of the gap gradually decreased on day 1-2 before new skin is generated on day 3. By day 4 dermal hyperproliferation is detected, followed by the scab formation on day 4-5, the wound is healed on day 6 when the thickened dermal layer is diminished, and the wound is hardly noticeable. The surface potential distribution over the wound measured by Dermacorder™ is indicated by the blue traces. As the wound healed, a significant decrease in electric field is demonstrated with the evidence of wound morphology provided.

Publication :

Imaging the electric field associated with mouse and human skin wounds <PDF>

Richard Nuccitelli, PhD¹; Pamela Nuccitelli, BA¹ ; Samdeo Ramlatchan, MS¹; Richard Sanger²; Peter J.S. Smith, PhD²

1. BioElectroMed Corporation, Burlingame, California, and

2. BioCurrents Research Center, Marine Biological Laboratories, Woods Hole, Massachusetts

Detecting Malignant Skin Lesions Non-invasively

When B16 murine melanoma cells are injected beneath the skin they form a melanoma tumor in a few days. As the tumor grows the electric field increases to an average level of 150 mV/mm. We can also detect other skin lesions by a change in surface potential of the overlying epidermis. The common characteristic of lesions that generate electrical signals appears to be inflammation. We speculate that cytokines released by lymphocytes influence the conductance of ion channels in the epidermis and this results in current flow between the epidermis and stratum corneum that generates the observed lateral electric field.