Method for producing an array of planar microparticles with surface molecular multiplexing, resulting array and use thereof

Abstract

A method for controlled production of an array of planar microparticles with the multiplexing of molecules on the surface thereof, intended to function as molecular sensors and/or actuators and a matrix (array) of microparticles, the surface thereof being printed with all of the molecular components required to provide the surface with functionality. Different molecular elements are multiplexed on the surface of each particle while they are supported on a substrate by means of a structural foot engraved below the particle. These microparticles can be released mechanically from the support on which they are produced using a controlled mechanical rupture method which is not chemically aggressive and therefore does not affect the molecules previously printed on the surface. The array and the particles contained therein offer great versatility in both chemical and/or biological applications.

1 - 26 . (canceled) 
     
     
         27 . A method for producing planar microparticles, the method comprising:
 a) preparing a structuration layer of a microparticle starting material on a first surface of substrate that serves as a support;   b) shaping the structuration layer to form microparticles, the shaping comprising shaping a geometry and lateral dimensions of the microparticles using a microelectronic lithography technique, and defining a thickness of the microparticles using an engraving technique;   c) forming feet in an upper portion of the substrate that is under the structuration layer in order to support each microparticle, by means of engraving techniques;   d) forming chemically functionalized microparticles by chemically functionalizing a surface of each microparticle supported on the feet using one or more molecular components and a molecule printing technique; and   e) individualizing and releasing the planar microparticles from the substrate by breaking each of the feet of the chemically functionalized microparticles by applying a mechanical breaking load.   
     
     
         28 . The method of  claim 27 , wherein each of the feet are under a respective microparticle, and wherein the formation of each of the feet comprises partially engraving the substrate from the first surface toward a second surface that is opposite the first surface using a microelectronic technique, each of the feet having a height and a width that varies through the height, the width decreasing from a first surface of the substrate to a midpoint of the height and increasing from the midpoint toward the second surface of the substrate 
     
     
         29 . The method according to  claim 27 , wherein the substrate is formed of a single material, said material being a silicon sheet, or by two materials, including a second material in the form of a layer that is located in the upper part of the substrate beneath the microparticle structuration layer. 
     
     
         30 . The method according to  claim 27 , wherein the structuration layer of the microparticle is a material selected from the group consisting of polycrystalline silicon, silicon oxide, nitride selected from the group consisting of silicon, gold, platinum, copper, aluminum, nickel, cobalt, chromium, metal oxides; tantalum, iron and aluminum silicates; and silicide selected from the group consisting of tantalum silicide, iron silicide and aluminum silicide; and wherein the starting material of the structuration layer and the upper portion of the substrate where the feet are engraved have a relationship between their rupture limits greater than or equal to 1. 
     
     
         31 . The method according to  claim 27 , wherein the preparation of the structuration layer in stage a) is carried out by depositing or by growing said structuration layer on top of the substrate by a microelectronics technique selected from the group consisting of thermal growth, chemical vapor deposition, sputtering and evaporation. 
     
     
         32 . The method according to  claim 27 , wherein the partial engraving of the foot is carried out via a lateral physical etching or a lateral chemical etching. 
     
     
         33 . The method according to  claim 27 , wherein the microparticles are shaped in stage b) by means of photo-lithographic techniques. 
     
     
         34 . The method according to  claim 27 , wherein the microparticles are shaped all with the same shape and size or in two or more groups with different shapes and sizes. 
     
     
         35 . The method according to  claim 27 , wherein the molecule-printing technique is selected from the group consisting of microcontact printing, dip-pen nanolithography and polymer-pen lithography technique. 
     
     
         36 . The method according to  claim 27 , wherein the molecular component is a molecule with chemical or biological activity, or both, selected from the group consisting of organic compounds, polymers, peptides, proteins, nucleotides, nucleic acids and any combination thereof. 
     
     
         37 . The method according to  claim 27 , wherein the surface of each microparticle is functionalized in stage d) with more than one different molecular element, or with a single molecular element more than one time. 
     
     
         38 . The method according to  claim 27 , wherein the mechanical breaking load is applied by means of a technique selected from the group consisting of rasping, cutting, cryofracturing, 
     
     
         39 . The method according to  claim 27 , wherein the mechanical breaking load comprises applying an adhesive material on the already functionalized surface of the microparticles and subsequently pulling it off, and dissolving the adhesive in media that does not affect the molecular functionalization of the microparticle. 
     
     
         40 . The method according to  claim 27 , which further comprises:
 f) gathering the individualized and released microparticles in a suspension medium.