ELECTRODE SENSOR KIT, ELECTRODE ASSEMBLY, AND TOPICAL PREPARATION FOR ESTABLISHING ELECTRICAL CONTACT WITH SKIN, USE THEREOF, AND METHOD OF ELECTRO-IMPEDANCE TOMOGRAPHY (EIT) IMAGING USING THESE

Abstract

An electrode sensor kit for establishing electrical contact with skin comprises at least one contact element and a preparation comprising a mixture of water and at least one lipid for enhancing electrical contact properties between said contact element and the skin, wherein said mixture forms an emulsion, in particular a water-in-oil or an oil-in-water emulsion, having a conductivity of less than 3 mS/cm. An electrode assembly for electrical impedance tomography which comprises said kit is characterized in that (a) said at least one contact element forms an electrode or sensor plate, and (b) said at least one contact element comprises a layer of said preparation.

Claims

1-33. (canceled)

34. A method of using an electrode sensor for performing biosignal measurements, comprising applying at least one contact element connectable to an analytical instrument and a preparation to skin of a test person, the preparation comprising a mixture of water and at least one lipid forming an emulsion having a conductivity of less than 1 mS/cm for enhancing electrical contact properties between the at least one contact element and the skin of the test person, the preparation interposed between the skin of the test person and the at least one contact element.

35. The method of claim 34, further comprising lining up in succession a plurality of contact elements with each contact element spaced apart a distance of 0.5 cm to 10 cm from an adjacent contact element.

36. The method of claim 34, further comprising performing biosignal measurements selected from the group consisting of an EIT-measurement, a heart-rate-measurement or an ECG-measurement.

37. The method of claim 34, further comprising forming the mixture into an oil-in-water or water-in-oil emulsion.

38. The method of claim 34, further comprising selecting the preparation with at least one additive selected from a group of functional additives consisting of hyaluronic acid or salt, hygroscopic substances, hydrophilic substances, saccharides or polysaccharide, polyacrylates, panthenol or D-panthenol, allantoin, aloe vera, glycosaminoglycans, or anionic nonsulfated glycosaminoglycans, algae or alginic acid, amino acids or proteins or hyaluronic acid or salt.

39. The method of claim 34, further comprising selecting the preparation with at least one alcohol, selected from the group consisting of mono-, di-, tri-, and polyhydroxy alcohols, glycerol, sorbitol or propylene glycol.

40. The method of claim 34, further comprising selecting the preparation with the at least one lipid is selected from the group consisting of oils, vegetable oils, phospholipids, diacylphospholipids, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylserine, phosphatidylinositol, or monoacyl derivatives thereor, cholesterol, natural lecithins, natural lecithins from egg, milk, soy, sunflower or oat; enzyme hydrolysed lecithins, enzyme hydrolysed soy lecithins; mixtures of monoacylphospholipids or diacylphospholipids or mixtures of monoacylphospholipids and diacylphospholipids containing 10 to 90 percent by weight of monoacylphospholipids.

41. The method of claim 34, further comprising selecting the preparation in the form of a fluid, a gel or a cream.

42. The method of claim 34, further comprising determining at least one of an electrical voltage, an electrical current, a voltage value, a current value, voltage or a current distribution on the skin.

43. The method of claim 34, further comprising applying the preparation to the skin at predetermined locations prior to application of electrical current or voltage or measurement of electrical values at the predetermined locations.

44. The method of claim 44, further comprising determining an electrical value of the biosignal measurements selected from the group consisting of electro impedance tomography measurements, heart-rate-measurements, or electro cardiograph measurements.

45. The method of claim 34, further comprising selecting the preparation having an amount of the at least one lipid in the range of 5 to less than 50 weight percent.

46. The method of claim 34, further comprising selecting the preparation having an amount of water in the range of 50 to 90 weight percent.

47. The method of claim 34, further comprising selecting the at least one contact element comprised of a material selected from the group consisting of at least one of metals, conductive polymers, textiles or conductive textiles.

48. The method of claim 34, further comprising selecting the at least one contact element comprised of a structure of porous material on a skin contacting surface, wherein a surface of the structure of porous material is at least one of uneven, pocketed or porous.

49. The method of claim 34, further comprising selecting the at least one contact element comprised of a material selected from the group consisting of at least one of metals, conductive polymers, textiles or conductive textiles.

50. An electrode sensor assembly for establishing electrical contact with skin, comprising: at least one contact element connectable to an analytical instrument, the at least one contact element comprising a surface for contacting the skin, said surface being coated or impregnated with a preparation comprising a mixture of water and at least one lipid for enhancing electrical contact properties between the contact element and the skin, and said mixture forming a water-in-oil or an oil-in-water emulsion having a conductivity of less than 1 mS/cm.

51. The electrode sensor assembly of claim 50, wherein the preparation further comprises at least one alcohol, selected from the group consisting of mono-, di-, tri-, and polyhydroxy alcohols, glycerol, sorbitol or propylene glycol.

52. The electrode sensor assembly of claim 50, wherein the at least one lipid is selected from the group consisting of oils, vegetable oils, phospholipids, diacylphospholipids, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylserine, phosphatidylinositol, or monoacyl derivatives thereor, cholesterol, natural lecithins, natural lecithins from egg, milk, soy, sunflower or oat; enzyme hydrolysed lecithins, enzyme hydrolysed soy lecithins; mixtures of monoacylphospholipids or diacylphospholipids or mixtures of monoacylphospholipids and diacylphospholipids containing 10 to 90 percent by weight of monoacylphospholipids.

53. The electrode sensor assembly of claim 50, an amount of the at least one lipid is in the range of 5 to less than 50 weight percent and wherein an amount of water is in the range of 50 to 90 weight percent.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0122] An embodiment of the present invention will now be described by way of example with reference to the accompanying drawings showing schematically in

[0123] FIG. 1: a cross sectional view of an electrode sensor kit;

[0124] FIG. 2: a frontal view of a representative section of electrode assembly;

[0125] FIG. 3 experimental setup.

DETAILED DESCRIPTION OF THE INVENTION

[0126] In FIG. 1 an exploded view of a cross sectional view of an electrode sensor assembly 1 according to the invention is schematically shown in relation to a living being's skin 2. The electrode sensor assembly 1 comprises a contact element 3. Said contact element 3 comprises an electrically conductive material. On the side of the contact element 3 facing the skin 2 (i.e. surface 5 of contact element 3), the contact element 3 is in contact with preparation 4. Contact element 3 and preparation 4 form said sensor assembly 1. The contact element 3 may comprise a porous structure and/or layer on at least one surface 5. Exemplarily said porous structure comprises a fabric, such as a conductive fabric. The preparation may penetrate into said pores, e.g. into said fabric. Furthermore the contact element 3 is connectable to an analytical instrument (not shown here).

[0127] In FIG. 2 a frontal view of an electrode assembly 1 for electrical impedance tomography is depicted. The electrode assembly 1 comprises several plate-like contact elements 3 which are attached to or integrated in a belt-like strap 6, such as for example a strip, in particular a strip of cloth, a belt, or a band. The contact elements 3 are arranged in mutual spaced apart manner. Advantageously said arrangement extends in longitudinal direction of the strip. Typically a contact element 3 comprises an elongate plate-like shape and advantageously the longitudinal extent of the contact element 3 is arranged transversely to the length of the strap 6 (as shown in FIG. 2). According to present invention each contact element 3 may be wetted with the preparation 4 as indicated by the dotted area.

[0128] Resistance measurements of topical preparations may be conducted with an experimental setup as depicted in FIG. 3. The experimental setup consists essentially of a container of non conducting material (7). In said container electrodes (8, 8′) of a defined surface are arranged in a mutual position set apart in a defined distance (9). The electrodes may be flat and arranged parallel, facing each other with their planes. Further in order to measure resistance and conductivity of a fluid, gel or cream, said substance is filled into the container (7), the electrodes are connected to a power source forming an electrical circuit and appropriate measurement instruments are connected to the circuit.

[0129] The described invention is useful to optimize the electrical properties of the contact between one or several electrodes, typically an array of electrodes, and skin in living beings, particularly humans.

[0130] While this invention is susceptible of embodiments in many different forms, there is described herein in detail, illustrated embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspects of the invention to the embodiments illustrated.

EXAMPLES

[0131] Below presented experimental setup comprehends the general framework to determine the conductance (or resistance) of a material, e.g. such as a fluid, a gel, or a cream.

[0132] Small plastic cubes/cuboids (7) of 1 cm.sup.3 or 2 cm.sup.3 (see FIG. 3) were filled with preparations according to present invention. Copper electrodes (8, 8′) of 1 cm.sup.2 were arranged to have a volume of 1 cm.sup.3 or 2 cm.sup.3 of preparation in between them at an electrode distance (9) of 1 cm or 2 cm, respectively. The resistance was measured with the programmable LCR—Bridge HM8118, by Hameg Instruments GmbH, Industriestrasse 6, D-63533 Mainhausen, Germany, at frequencies of 200 kHz, 100 kHz, or 50 kHz.

[0133] Tested preparations according to present invention comprise compositions within the following range of example 1, see table below. Desired compositions comprise values within the closer range presented in the third column of the table below.

TABLE-US-00001 desired range Example 1 of example 1 (in weight (in weight percentage) percentage) Water 50-80 55-77 Oil/s 20-45 20-40 Alcohol/s  1-20  4-15 Additives 0-5 0.5-4  

[0134] The additives comprise skin compatible surfactants (surface active agents), optionally also humectants, odorants, and/or colorants etc.

[0135] Comparative examples were prepared from commercially available electrode creams and electrode sprays:

[0136] Comparative example 1: from Sigma, electrode cream, REF 17-05, by Parker Laboratories, Inc.

[0137] Comparative example 2: Dispo Contact, EKG-Elektrode Spray, Pharmacode 2817886.

[0138] Measured exemplary values of inventive preparations are presented in the following table. The tested preparation of example 1 is particularly suited for EIT belt applications. The different frequencies used show a small effect only.

TABLE-US-00002 200 kHz 100 kHz 50 kHz Comparative example 1 15.6 mS/cm 15.5 mS/cm 15.4 mS/cm Comparative example 2 75.6 mS/cm 74.1 mS/cm 77.5 mS/cm Example 1 0.253 mS/cm  0.239 mS/cm  0.227 mS/cm