Specific delivery of agrochemicals

Abstract

Described is the specific delivery of agrochemicals to plants. More specifically, described is a composition having a targeting agent comprising at least one binding domain that specifically binds to a binding site on an intact living plant and an agrochemical or a combination of agrochemicals. Also described is a binding domain that specifically binds the binding site on an intact living plant. More specifically, described are binding domains comprising a peptide sequence that comprises four framework regions and three complementary-determining regions, or any suitable fragment thereof, so that the binding domains are able to bind or retain a carrier onto a plant. Described are binding domains that specifically bind trichomes, stomata, cuticle, lenticels, thorns, spines, root hairs, or wax layer. Described is a method for delivery of agrochemicals to a plant, for improving the deposition of agrochemicals on a plant, and for retaining the agrochemicals on a plant, using targeting agents comprising the binding domains, and to a method for protecting a plant against biotic or abiotic stress or controlling plant growth using the same. Also, described is a method for manufacturing a specifically targeting agrochemical carrier.

1 . A process for producing specifically targeting microcapsules, the process comprising:
 emulsifying into a continuous aqueous phase an organic phase in which a to be encapsulated agrochemical or combination of agrochemicals is dissolved or dispersed to form an emulsion of droplets of the organic phase in the continuous aqueous phase;   causing an aqueous suspension of microcapsules with polymer walls having anchor groups at their surface to be formed; and   covalently linking at least one targeting agent to the anchor groups at the microcapsule surface, at a ratio from about 0.01 μg to about 1 μg targeting agent per square centimeter microcapsular surface.   
     
     
         2 . The process of  claim 1 , further comprising:
 causing polymerization of polyfunctional monomers or pre-polymers present in the organic phase to form an aqueous suspension of microcapsules having anchor groups at their surface.   
     
     
         3 . The process of  claim 2 , further comprising:
 adding to the emulsion a monomer- or pre-polymer reactant component containing anchor groups.   
     
     
         4 . The process of  claim 1 , further comprising:
 emulsifying into the continuous aqueous phase an organic phase which contains a pre-polymer or mixture of pre-polymers containing anchor groups, causing in situ self-condensation of the pre-polymers surrounding the droplets of organic phase to form an aqueous suspension of microcapsules having polymer walls with anchor groups at their surface.   
     
     
         5 . The process of  claim 1 , wherein the process comprises:
 emulsifying into the continuous aqueous phase an organic phase in which a to be encapsulated agrochemical or combination of agrochemicals is dissolved or dispersed to form an emulsion of droplets of the organic phase in the continuous aqueous phase;   adding to the continuous aqueous phase a water-soluble pre-polymer or mixture of pre-polymers, containing anchor groups;   causing in situ self-condensation of the pre-polymers surrounding the droplets of organic phase to form an aqueous suspension of microcapsules with polymer walls having anchor groups at their surface; and   covalently linking at least one targeting agent to the anchor groups at the microcapsule surface, at a ratio from about 0.01 μg to about 1 μg targeting agent per square centimeter microcapsular surface.   
     
     
         6 . The process of  claim 1 , wherein the targeting agent comprises an antigen binding protein. 
     
     
         7 . The process of  claim 6 , wherein the antigen binding protein is derived from a camelid antibody. 
     
     
         8 . The process of  claim 7 , wherein the antigen binding protein is comprised in a VHH. 
     
     
         9 . A specifically targeting microcapsule produced of a process comprising:
 emulsifying into a continuous aqueous phase an organic phase comprising an agrochemical, together with polyfunctional monomers or pre-polymers, to form an emulsion of droplets of the organic phase in the continuous aqueous phase, thus forming an aqueous suspension of microcapsules, microcapsules thereof having polymer walls with anchor groups at each microcapsule's surface; and   covalently linking a targeting agent to the anchor groups at the microcapsule surface, at a ratio from about 0.01 μg to about 1 μg targeting agent per square centimeter microcapsular surface.   
     
     
         10 . The specifically targeting microcapsule, of  claim 9 , able to bind an agrochemical or combination of agrochemicals to a surface. 
     
     
         11 . The specifically targeting microcapsule of  claim 9 , having a targeting agent comprising an antigen binding protein. 
     
     
         12 . The specifically targeting microcapsule of  claim 11 , wherein the antigen binding protein is derived from a camelid antibody. 
     
     
         13 . The specifically targeting microcapsule of  claim 12 , wherein the antigen binding protein is comprised in a VHH sequence. 
     
     
         14 . An agrochemical composition comprising a suspension or dispersion of the specifically targeting microcapsules of  claim 9  in an aqueous medium. 
     
     
         15 . A method of protecting a plant, or modulating viability, growth or yield of a plant or plant part and/or to modulate gene expression in a plant or plant part, the method comprising:
 utilizing the agrochemical composition of  claim 14  to protect a plant and/or to modulate the viability, growth or yield of a plant or plant part, and/or to modulate gene expression in a plant or plant part.   
     
     
         16 . The process of  claim 1 , wherein the continuous aqueous phase comprises a surfactant. 
     
     
         17 . A process for producing a microcapsule, the process comprising:
 emulsifying into a continuous aqueous phase an organic phase comprising an agrochemical and polyfunctional monomers or pre-polymers, to form an emulsion of droplets of the organic phase in the continuous aqueous phase, thus forming an aqueous suspension of microcapsules, wherein microcapsules thereof have polymer walls with anchor groups at the microcapsule's surface; and   covalently linking a targeting agent to the anchor groups at the microcapsule surface, at a ratio from about 0.01 μg to about 1 μg targeting agent per square centimeter microcapsular surface.   
     
     
         18 . The process of  claim 17 , wherein the continuous aqueous phase comprises a surfactant. 
     
     
         19 . The process of  claim 17 , wherein the organic phase comprises a combination of agrochemicals. 
     
     
         20 . The process of  claim 17 , comprising covalently linking more than one targeting agent to the anchor groups at the microcapsule surface.