EPR (Electron Paramagnetic Resonance) as Method of Non-invasive Characterization of Melanin Content in Skins With Different Phototypes

Skin Pigmentation Clinical Trial

Official title:

EPR (Electron Paramagnetic Resonance) as Method of Non-invasive Characterization of Melanin Content in Skins With Different Phototypes

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT04270903
• Other study ID #: MELA-RPE-PHOTOTYPE
• Status: Completed
• Start date: March 22, 2019
• Est. completion date: December 20, 2019

Study information

• Verified date: February 2020
• Source: Université Catholique de Louvain
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

The aim of this study is to assess the signal of melanin using Electron Paramagnetic resonance (EPR). Melanin is a paramagnetic pigment detectable by EPR. Recent advances in instrumentation allows the application of EPR in human beings. The characterization of melanin by EPR could be potentially interesting in the context of melanoma detection and characterization. While another clinical study is currently ongoing aiming at demonstrating the feasibility of the non-invasive detection of the EPR signal of melanin in melanoma patients, it is crucial to have a control group with healthy skin. The aim of the present study is to assess the influence of skin pigmentation of the EPR signal recorded. In the present clinical study, the EPR signal of melanin will be characterized in healthy skin with different phototypes (1-2, 3-4, 5-6) to assess the potential influence of skin pigmentation on the EPR signal.

Description:

Electron paramagnetic resonance (EPR), also known as electron spin resonance (ESR), is a spectrometric method enabling the observation of the absorption of energy by the free radicals contained by a sample immerged in a strong homogenous magnetic field. An EPR spectrum reveals only the presence of paramagnetic centers and can thus only be observed with samples containing lone unpaired electrons. In water-containing biological environments, most of free radicals are very reactive and have a very short life. To detect such species, a strategy is to use extrinsic molecules that will react with these species to form EPR measurable adducts. This technique is called "spin trapping". In contrast, the study of stable free radicals does not require the use of spin-trap agents. Melanins are part of the rare stable biological radicals directly observable with EPR. In practice, melanin is the only endogenous stable radical that can be detected using 1 GHz EPR.

The aim of the present study is to measure the EPR signal recorded from skin with different pigmentations. 45 healthy volunteers will be enrolled:

15 subjects with phototype 1-2, 15 subjects with phototypes 3-4, 15 subjects with phototypes 5-6. The parameters described hereafter will be investigated:

• g factor (resonance condition); expected g=2.005;

• shape of the signal, presence of a shoulder at g=2.01 due to pheomelanin;

• intensity of the signal (signal height, double integration, double integration relative to reference).

This will provide a database for other ongoing studies carried out in patients with suspicious lesion (nevi vs melanoma)

Recruitment information / eligibility

• Status: Completed
• Enrollment: 45
• Est. completion date: December 20, 2019
• Est. primary completion date: September 17, 2019
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Healthy volunteers with skin belonging to Phototype I-II, III-IV, V-VI

Exclusion Criteria:

• Subjects under 18 years

• Subjects with pacemakers

• Subjects with non-removable implants with metal or otherwise not known to be MRI-compatible.

• Pregnant women

Related Conditions & MeSH terms

• Free Radicals
• Magnetic Resonance
• Phototype
• Skin Pigmentation

Intervention

Device:
• EPR measurement
Subject put in a magnet, magnetic field sweeping around 40 mTesla. Irradiation with a wave with a frequency of 1.1 GHz. A resonator (surface coil) is put at the surface of the skin (arm). The EPR signal is recorded.

Locations

Country	Name	City	State
Belgium	Université catholique de Louvain	Brussels

Sponsors (1)

Lead Sponsor	Collaborator
Université Catholique de Louvain

Country where clinical trial is conducted

Belgium, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Measurement of the EPR signal intensity	Signal height / Double integration / Double integration relative to reference signal	Through study completion (6 months)