Biosensor and method of manufacturing such a biosensor

Patent metadata

Field	Value
Publication number	US-9835576-B2
Application number	US-201214000957-A
Country	US
Kind code	B2
Filing date	Feb 14, 2012
Priority date	Feb 22, 2011
Publication date	Dec 5, 2017
Grant date	Dec 5, 2017

Abstract

A method of manufacturing a biosensor having a microbeam linked to a support, at least one electrode a biological molecule A grafted onto the microbeam in a different zone from the zone where the electrode is embedded, and a mechanoelectrical transducer for converting variations of the mechanical properties of the microbeam into an electrical signal, when the biological molecule A is placed in contact with a biological molecule B to be detected and/or quantified. The method includes: formation of an electrode on fluoropolymer material sheet, passivation of the electrode(s), creation of the form of the biosensor in the sheet of polymer material and separation of this form from the sheet, functionalization either of a prefunctionalized zone or of a zone of the microbeam, this zone being different from the zone wherein the electrode is embedded, and grafting of a biological molecule A onto the functionalized zone.

First claim

The invention claimed is:

1. A process for the fabrication of a biosensor, said biosensor comprising:
a microbeam, which is a mobile part of the biosensor, connected to a support,
at least two electrodes, at least a part of each electrode being embedded in the microbeam,
at least one biological molecule (A) grafted onto the microbeam in a location different from where said electrodes are embedded,
a piezoelectric transducer for converting variations in the mechanical properties of the microbeam into an electrical signal, when the at least one biological molecule (A) is brought into contact with a biological molecule (B) to be detected and/or quantified, wherein
the microbeam and its support are made of a fluoropolymer material and form an integral component,
the process comprising the following steps:
(a) formation of at least two electrodes on a sheet made of a fluoropolymer material,
(b) passivation of the at least two electrodes,
(c) creation of a final desired shape of the biosensor in the sheet made of a fluoropolymer material, said desired shape being defined by the microbeam and its support both made of said fluoropolymer material and forming an integral component as well as the at least two electrodes at least a part of each electrode being embedded in the microbeam and, separation of the final desired shape from the sheet,
(d) optionally, prefunctionalization of a zone of the microbeam, the zone being at a location different from where the at least two electrodes are embedded,
(e) functionalization of either the zone prefunctionalized in step (d), when step (d) is carried out, or of a zone of the microbeam, this zone being different than the zone wherein the at least one electrode is embedded,
(f) grafting of at least one biological molecule (A) onto the functionalized zone obtained in step (d), and wherein step (a) further comprises the following steps:
(a1) deposition or grafting of a mask made of a material which is not transparent to VUV radiation, comprising at least one opening or zone made of a material which is transparent to VUV radiation, on the sheet made of fluoropolymer material, this opening or zone having the desired shape of the at least two electrodes,
(a2) irradiation by said VUV radiation, under an inert gas, of the sheet obtained in step (a1),
(a3) removal of the mask,
(a4) grafting of acrylic acid molecules, so as to form a poly(acrylic) acid (PAA) polymer in the irradiated zones obtained in step (a2),
(a5) binding of Cu 2+ ions, by chelation, onto the PAA grafted in step (a4),
(a6) reduction of the Cu 2+ ions into copper microparticles or nanoparticles,
(a7) growth, on the zones containing the copper microparticles or nanoparticles, of a layer of copper or of gold, by means of a metalization bath.

2. The process as claimed in claim 1 , wherein step (c) is performed between step (e) and step (f).

3. The process as claimed in claim 1 , wherein step (c) is performed after step (f) of grafting.

4. The process as claimed in claim 1 , further comprising step (d) and wherein step (c) is performed after step (d) and before step (e).

5. The process as claimed in claim 1 , wherein step (a) further comprises the following steps:
(a8) deposition of a layer of positive-type resin, sensitive to UV radiation, on the sheet made of a fluoropolymer material,
(a9) irradiation, with said UV radiation, of the layer formed in step (a8) through a mask made of a material which is not transparent to UV radiation, comprising at least one opening or one zone made of a material which is transparent to said UV radiation, this opening or this zone having the desired shape of the at least two electrodes,
(a10) elimination of the irradiated resin and of the mask,
(a11) formation of a PAA polymer, in the zones where the resin has been eliminated, via diazonium salt technology,
(a12) binding of Cu 2+ ions, by chelation, onto the PAA formed in step (all),
(a13) reduction of the chelated Cu 2+ ions so as to form copper microparticles or nanoparticles making it possible to autocatalyze the metalization bath of step (a14),
(a14) growth, by means of a metalization bath, of a layer of copper or of gold on the zones comprising the copper microparticles or nanoparticles,
(a15) elimination of the remaining photosensitive resin.

6. The process as claimed in claim 1 , wherein step (a) further comprises the following steps:
(a16) formation of a PAA polymer on the sheet made of a fluoropolymer material, via diazonium salt technology,
(a17) binding of Cu 2+ ions, by chelation, onto the PAA formed in step (a16),
(a18) reduction of the chelated Cu 2+ ions into copper microparticles or nanoparticles,
(a19) growth, by means of a metalization bath, of a layer of copper or of gold on the zones comprising the copper microparticles or nanoparticles, said metallization bath being activated by the reduction performed during step (a18),
(a20) deposition of a layer of positive-type resin, sensitive to UV radiation, on the surface of the sheet made of fluoropolymer material and which has been metalized, obtained in step (a19),
(a21) irradiation, with said UV radiation, of the layer formed in step (a20), through a mask made of a material which is transparent to said UV radiation, comprising at least one opening or one zone made of a material which is not transparent to said UV radiation, this opening or this zone silhouetting the desired shape of the at least two electrodes
(a22) elimination of the irradiated resin and of the mask,
(a23) elimination of the copper or of the gold, by chemical etching in the zones where the resin has been eliminated,
(a24) elimination of the remaining photosensitive resin.

7. The process as claimed in claim 1 , wherein step (a) further comprises the following steps:
(a25) irradiation of a sheet made of a fluoropolymer material with VUV radiation, under an inert gas,
(a26) grafting, onto the sheet obtained in step (a25), of acrylic acid molecules so as to form an acrylic acid polymer PAA,
(a27) binding of Cu 2+ ions, by chelation, onto the PAA grafted in step (a26),
(a28) reduction of the Cu 2+ ions into copper microparticles or nanoparticles,
(a29) growth, on the zones comprising the copper microparticles or nanoparticles, of a layer of copper or of gold, by means of a metalization bath,
(a30) deposition of a layer of positive-type resin, sensitive to UV radiation, on the metalized sheet made of a fluoropolymer material, obtained in step (a29),
(a31) irradiation, with said UV radiation, of the layer formed in step (a30), through a mask made of a material which is transparent to said UV radiation, comprising an opening or a zone made of a material which is not transparent to said UV radiation, this opening or this zone silhouetting the desired shape of the at least two electrodes,
(a32) elimination of the irradiated resin and of the mask,
(a33) elimination, by chemical etching, in the zones where the resin has been irradiated, either of the layer of copper if formed in step (a29), or of the layer of gold, if formed in step (a29),
(a34) elimination of the remaining resin.

8. The process as claimed in claim 1 , wherein step (b) further comprises the following steps:
(b1) spin-coating of SU-8-negative-type epoxy resin onto the sheet made of a fluoropolymer material comprising the at least two electrodes,
(b2) deposition or grafting, onto the layer of resin obtained in step (c1), of a mask made of a material which is not transparent to said UV radiation, comprising an opening or a zone made of a material which is transparent to UV radiation, this opening or zone having the shape of the at least two electrodes,
(b3) irradiation, with said UV radiation, of the layer of SU-8-resin through th

Assignees

• Polesel Maris Jérôme
• Berthelot Thomas
• Commissariat Energie Atomique

Inventors

• Polesel Maris Jérôme
• Berthelot Thomas

Classifications

• G01N27/327 Primary

  Biochemical electrodes {, e.g. electrical or mechanical details for in vitro measurements} · CPC title

• B82Y15/00

  Nanotechnology for interacting, sensing or actuating, e.g. quantum dots as markers in protein assays or molecular motors · CPC title

• B82Y40/00

  Manufacture or treatment of nanostructures · CPC title

• G01N2291/0427

  Flexural waves, plate waves, e.g. Lamb waves, tuning fork, cantilever · CPC title

• G01N29/022 Primary

  Fluid sensors based on microsensors, e.g. quartz crystal-microbalance [QCM], surface acoustic wave [SAW] devices, tuning forks, cantilevers, flexural plate wave [FPW] devices (microdevices per se B81B) · CPC title