An anti-microbial coating (10, 10', 10", 10′′′, 10ʺʺ) of a substrate, wherein the coating (10, 10', 10", 10′′′, 10ʺʺ) is obtained by applying an aqueous solution or suspension in droplet form onto a surface of the substrate by means of an electrostatic spraying method, the aqueous solution or suspension containing at least one metal oxide soluble therein and/or at least one metal salt, the coating containing at least one metal oxide and/or at least one metal salt, wherein the coating (10, 10', 10", 10′′′, 10ʺʺ) is developed in the form of a matrix structure, the matrix structure having a plurality of islands spaced apart from one another, and the islands having a diameter in a range in particular from about 0.1 μm to about 500 μm, preferably from about 1 μm to about 200 μm, particularly preferably from about 2 μm to about 100 μm, and the islands each being spaced apart from one another in accordance with their diameter, wherein a metal oxide constitution is described by the formula A c O d or Me e O d, wherein A is selected from the elements of group 4 and Me is selected from the elements of group 6 of the periodic table of the elements (IUPAC nomenclature) and 0 is the element oxygen, wherein c, d and e independently of one another can take a value between 0 and 24, i.e. not 0 and 24, the metal oxide preferably being TiO 2, ZrO 2, HfO 2, molybdenum oxide or tungsten oxide, and wherein a metal salt constitution is described by the formula XBO 3, wherein X is selected from the elements of groups 5, 7, 8, 9, 10, 11, 12, the lanthanides or the actinides, and B is selected from the elements of group 15 of the periodic table of the elements (IUPAC nomenclature), and 0 is the element oxygen. wherein the coating (10, 10', 10", 10′′′, 10ʺʺ) is obtained by applying an aqueous solution or suspension in droplet form onto a surface of the substrate by means of an electrostatic spraying method, the aqueous solution or suspension containing at least one metal oxide soluble therein and/or at least one metal salt, the coating containing at least one metal oxide and/or at least one metal salt, wherein the coating (10, 10', 10", 10′′′, 10ʺʺ) is developed in the form of a matrix structure, the matrix structure having a plurality of islands spaced apart from one another, and the islands having a diameter in a range in particular from about 0.1 μm to about 500 μm, preferably from about 1 μm to about 200 μm, particularly preferably from about 2 μm to about 100 μm, and the islands each being spaced apart from one another in accordance with their diameter, wherein a metal oxide constitution is described by the formula A c O d or Me e O d, wherein A is selected from the elements of group 4 and Me is selected from the elements of group 6 of the periodic table of the elements (IUPAC nomenclature) and 0 is the element oxygen, wherein c, d and e independently of one another can take a value between 0 and 24, i.e. not 0 and 24, the metal oxide preferably being TiO 2, ZrO 2, HfO 2, molybdenum oxide or tungsten oxide, and wherein a metal salt constitution is described by the formula XBO 3, wherein X is selected from the elements of groups 5, 7, 8, 9, 10, 11, 12, the lanthanides or the actinides, and B is selected from the elements of group 15 of the periodic table of the elements (IUPAC nomenclature), and 0 is the element oxygen.