Supramolecular capsules

Abstract

Provided is a capsule having a shell of material that is a supramolecular cross-linked network. The network is formed from a host-guest complexation of cucurbituril (the host) and one or more building blocks comprising suitable guest functionality. The complex non-covalently crosslinks the building block and/or non-covalently links the building block to another building block thereby forming the supramolecular cross-linked network. The capsules are obtained or obtainable by the complexation of a composition comprising cucurbituril and one or more building blocks having suitable cucurbituril guest functionality thereby to form a supramolecular cross-linked network.

1 . A capsule having a shell which is obtainable from the complexation of a composition comprising a host and one or more building blocks having suitable host guest functionality thereby to form a supramolecular cross-linked network. 
     
     
         2 . The capsule of  claim 1 , wherein the host is selected from cucurbituril, cyclodextrin, calix[n]arene, and crown ether, and the one or more building blocks have suitable host guest functionality for the cucurbituril, cyclodextrin, calix[n]arene or crown ether host. 
     
     
         3 . The capsule of  claim 2 , wherein the host is cucurbituril and the one or more building blocks have suitable cucurbituril guest functionality. 
     
     
         4 . The capsule of  claim 3 , wherein the shell is obtainable from the complexation of (a) a composition comprising cucurbituril and (1) or (2); or (b) a composition comprising a plurality of covalently linked cucurbituril and (1), (2) or (3), wherein:
 (1) comprises a first building block covalently linked to a plurality of first cucurbituril guest molecules and a second building block covalently linked to a plurality of second cucurbituril guest molecules, wherein a first guest molecule and a second guest molecule together with cucurbituril are suitable for forming a ternary guest-host complex,   (2) comprises a first building block covalently linked to a plurality of first cucurbituril guest molecules and a plurality of second cucurbituril guest molecules, wherein a first and a second guest molecule together with cucurbituril are suitable for forming a ternary guest-host complex and optionally the composition further comprises a second building block covalently linked to one or more third cucurbituril guest molecules, one or more fourth cucurbituril guest molecules or both, wherein a third and a fourth molecule together with cucurbituril are suitable for forming a ternary guest-host complex, and/or the first and fourth molecules together with cucurbituril are suitable for forming a ternary guest-host complex, and/or the second and third molecules together with cucurbituril are suitable for forming a ternary guest-host complex; and   (3) comprises a first building block covalently linked to a plurality of first cucurbituril guest molecules, wherein the first guest molecule together with the cucurbituril are suitable for forming a binary guest-host complex. Optionally the composition further comprises a second building block covalently linked to one or more second cucurbituril guest molecules, wherein the second guest molecule together with the cucurbituril are suitable for forming a binary guest-host complex.   
     
     
         5 . The capsule of  claim 4 , wherein the shell is obtainable from the complexation of a composition comprising cucurbituril and (1) or (2). 
     
     
         6 . The capsule of  claim 5 , wherein the shell is obtainable from the complexation of a composition comprising cucurbituril and (1). 
     
     
         7 . The capsule of  claim 3 , wherein the cucurbituril is selected from CB[8] and variants and derivatives thereof. 
     
     
         8 . The capsule of  claim 7 , wherein the cucurbituril is CB[8]. 
     
     
         9 . The capsule of  claim 7 , wherein the cucurbituril forms a ternary complex with a first guest molecule and a second guest molecule, and the first and second guest molecules are selected from the following pairs:
 viologen and naphthol;   viologen and dihydroxybenzene;   viologen and tetrathiafulvalene;   viologen and indole;   methylviologen and naphthol;   methylviologen and dihydroxybenzene;   methylviologen and tetrathiafulvalene;   methylviologen and indole;   N,N′-dimethyldipyridyliumylethylene and naphthol;   N,N′-dimethyldipyridyliumylethylene and dihydroxybenzene;   N,N′-dimethyldipyridyliumylethylene and tetrathiafulvalene;   N,N′-dimethyldipyridyliumylethylene and indole;   2,7-dimethyldiazapyrenium and naphthol;   2,7-dimethyldiazapyrenium and dihydroxybenzene;   2,7-dimethyldiazapyrenium and tetrathiafulvalene; and   2,7-dimethyldiazapyrenium and indole.   
     
     
         10 . The capsule of  claim 1 , wherein the first building block is a polymeric molecule. 
     
     
         11 . The capsule of  claim 10 , wherein the polymeric molecule is or comprises a poly(meth)acrylate-, a polystyrene- and/or a poly(meth)acrylamide polymer. 
     
     
         12 . The capsule of  claim 10 , wherein the polymeric molecule comprises a detectable label. 
     
     
         13 . The capsule of  claim 1 , wherein the second building block, where present, is a particle. 
     
     
         14 . The capsule of  claim 13 , wherein the particle is or comprises gold or silver or mixtures thereof. 
     
     
         15 . The capsule according to  claim 1 , wherein the capsule size is in range from 10 to 100 μm in diameter. 
     
     
         16 . The capsule according to  claim 1 , wherein the capsule diameter has a relative standard deviation (RSD) of at most 10%. 
     
     
         17 . The capsule according to  claim 1 , wherein the shell pore size is in range 1 to 20 nm. 
     
     
         18 . The capsule according to  claim 1 , wherein the capsule encapsulates a component. 
     
     
         19 . The capsule according to  claim 18 , wherein the component is a biological molecule. 
     
     
         20 . A method for the preparation of a capsule having a shell, the method comprising the step of:
 (i) contacting a flow of a first phase and a flow of a second phase in a channel, thereby to generate in the channel a dispersion of discrete regions, preferably droplets, of the second phase in the first phase, wherein the second phase comprises cucurbituril and one or more building blocks having suitable cucurbituril guest functionality suitable to form a supramolecular cross-linked network, thereby to form a capsule shell within the discrete region, wherein the first and second phases are immiscible.   
     
     
         21 . The method of  claim 20 , wherein the second phase either (a) a cucurbituril and (1) or (2); or (b) a plurality of covalently linked cucurbituril and (1), (2) or (3), wherein:
 (1) comprises a first building block covalently linked to a plurality of first cucurbituril guest molecules and a second building block covalently linked to a plurality of second cucurbituril guest molecules, wherein a first guest molecule and a second guest molecule together with cucurbituril are suitable for forming a ternary guest-host complex.   (2) comprises a first building block covalently linked to a plurality of first cucurbituril guest molecules and a plurality of second cucurbituril guest molecules, wherein a first and a second guest molecule together with cucurbituril are suitable for forming a ternary guest-host complex and optionally the composition further comprises a second building block covalently linked to one or more third cucurbituril guest molecules, one or more fourth cucurbituril guest molecules or both, wherein a third and a fourth molecule together with cucurbituril are suitable for forming a ternary guest-host complex, and/or the first and fourth molecules together with cucurbituril are suitable for forming a ternary guest-host complex, and/or the second and third molecules together with cucurbituril are suitable for forming a ternary guest-host complex; and   (3) comprises a first building block covalently linked to a plurality of first cucurbituril guest molecules, wherein the first guest molecule together with the cucurbituril are suitable for forming a binary guest-host complex. Optionally the composition further comprises a second building block covalently linked to one or more second cucurbituril guest molecules, wherein the second guest molecule together with the cucurbituril are suitable for forming a binary guest-host complex.   
     
     
         22 . The method of  claim 21  wherein the second phase comprises cucurbituril and (1) or (2). 
     
     
         23 . The method of  claim 22 , wherein the second phase comprises cucurbituril and (1). 
     
     
         24 . The method of  claim 20 , wherein the cucurbituril is selected from CB[8] and variants and derivatives thereof. 
     
     
         25 . The method of  claim 24 , wherein the cucurbituril is CB[8]. 
     
     
         26 . The method of  claim 24 , wherein the cucurbituril forms a ternary complex with a first guest molecule and a second guest molecule, and the first and second guest molecules are selected from the following pairs:
 viologen and naphthol;   viologen and dihydroxybenzene;   viologen and tetrathiafulvalene;   viologen and indole;   methylviologen and naphthol;   methylviologen and dihydroxybenzene;   methylviologen and tetrathiafulvalene;   methylviologen and indole;   N,N′-dimethyldipyridyliumylethylene and naphthol;   N,N′-dimethyldipyridyliumylethylene and dihydroxybenzene;   N,N′-dimethyldipyridyliumylethylene and tetrathiafulvalene;   N,N′-dimethyldipyridyliumylethylene and indole;   2,7-dimethyldiazapyrenium and naphthol;   2,7-dimethyldiazapyrenium and dihydroxybenzene;   2,7-dimethyldiazapyrenium and tetrathiafulvalene; and   2,7-dimethyldiazapyrenium and indole.   
     
     
         27 . The method of  claim 20 , wherein the first building block is a polymeric molecule. 
     
     
         28 . The method of  claim 27 , wherein the polymeric molecule is or comprises a poly(meth)acrylate-, a polystyrene- and/or a poly(meth)acrylamide polymer. 
     
     
         29 . The method of  claim 27 , wherein the polymeric molecule comprises a detectable label. 
     
     
         30 . The method of  claim 20 , wherein the second building block, where present, is a particle. 
     
     
         31 . The method of  claim 30 , wherein the particle is or comprises gold or silver or mixtures thereof. 
     
     
         32 . The method of  claim 20 , wherein the second phase is an aqueous phase and the first phase is a water immiscible phase. 
     
     
         33 . The method of  claim 20 , wherein the second phase further comprises a component for encapsulation, and the step (i) provides a capsule having a shell encapsulating the component. 
     
     
         34 . The method of  claim 20 , wherein the method further comprises the step of (ii) collecting the outflow from the channel, thereby to obtain a droplet, which contains a capsule. 
     
     
         35 . The method of  claim 34 , further comprising the step of drying the capsule obtained in step (ii). 
     
     
         36 . A method of delivering a component to a location, the method comprising the steps of:
 (i) providing a capsule having a shell encapsulating a component, as defined in  claim 18 ;   (ii) delivering the capsule to a target location;   (iii) releasing the component from the shell.