US5200334A — Sol-gel encapsulated enzyme

Claim 1

Independent Claim 148 words

A process for the production of a porous, transparent sol-gel glass containing an alcohol sensitive active biological material entrapped therein comprising: (a) forming a single phase sol by mixing a metal alkoxide in a non-alcoholic medium comprising water and an acid catalyst in a container exposed to ultrasonic energy, the mixture having a pH not greater than about 2; (b) removing the ultrasonic energy and raising the pH of the sol to about 5 to 7 by the addition of a buffering agent; (c) adding said active biological material to the buffered sol; (d) forming a gel and allowing the gel to age; and (e) allowing at least a portion of the water in the gel to evaporate so that the volume of the product produced in step (d) is decreased and the active biological material is trapped in a monolith of the gel having a reduced volume.

Claim 2

Dependent Claim 148 words

A process for the production of a porous, transparent sol-gel glass containing an alcohol sensitive active biological material entrapped therein comprising: (a) forming a single phase sol by mixing a metal alkoxide in a non-alcoholic medium comprising water and an acid catalyst in a container exposed to ultrasonic energy, the mixture having a pH not greater than about 2; (b) removing the ultrasonic energy and raising the pH of the sol to about 5 to 7 by the addition of a buffering agent; (c) adding said active biological material to the buffered sol; (d) forming a gel and allowing the gel to age; and (e) allowing at least a portion of the water in the gel to evaporate so that the volume of the product produced in step (d) is decreased and the active biological material is trapped in a monolith of the gel having a reduced volume.

Claim 3

Dependent Claim 24 words

The process of claim 1 wherein a pre-buffer aging step is added after exposing the mixture to ultrasound but prior to buffering the mixture.

Claim 4

Dependent Claim 16 words

The process of claim 1 wherein the gel is aged for at least about ten days.

Claim 5

Dependent Claim 14 words

The process of claim 1 wherein step(e) continues for at least about ten days.

Claim 6

Dependent Claim 13 words

The process of claim 1 wherein the active biological material is a protein.

Claim 7

Dependent Claim 38 words

The process of claim 1 wherein the active biological material is selected from the group consisting of nuclease, protease, oxidase, esterase, isomerase, metal and metal ion binders, bicarbonate binders, free radical inhibitors, reversible oxygen binders and combinations thereof.

Claim 8

Dependent Claim 47 words

The process of claim 1 wherein the active biological material is selected from the group consisting of RNase A, RNase T1, protease k, chymotrypsin, alcohol oxidase, glucose oxidase, acetylcholine esterase, phosphodiesterase II, aldolase, glucose isomerase, hemoglobin, myoglobin, cytochrome c, aequorin, transferase, urease, superoxide dismutase and combinations thereof.

Claim 9

Dependent Claim 27 words

The process of claim 1 wherein the resultant product is a three dimensional object with a smallest dimension being from about 1000 Angstroms to about 0.5 cm.

Claim 10

Dependent Claim 30 words

The process of claim 1 wherein the volume of the product of step (e) is reduced to about twelve percent (12%) of the volume of the product of step (d).

Claim 11

Dependent Claim 18 words

The process of claim 1 wherein the gel is aged for about 2 days to about 21 days.

Claim 12

Dependent Claim 19 words

The process of claim 1 wherein the aged gel is dried for about 8 days to about 60 days.

Claim 13

Dependent Claim 140 words

A porous, transparent sol-gel glass having entrapped therein an active biological material wherein the glass is prepared by: (a), forming a single phase sol by mixing a metal alkoxide in a non-alcoholic medium comprising water and an acid catalyst and exposing the mixture to ultrasonic energy, the mixture having a pH not greater than about 2; (b) removing the ultrasonic energy and raising the pH of the sol to about 5 to 7 by the addition of a buffering agent; (c) adding an active biological material to the buffered sol; (d) forming a gel and allowing the gel to age; and (e) allowing at least a portion of the water in the gel to evaporate so that external dimensions of the gel produced in step (d) are reduced and the active biological material is held within the structure after evaporation.

Claim 14

Dependent Claim 140 words

A porous, transparent sol-gel glass having entrapped therein an active biological material wherein the glass is prepared by: (a), forming a single phase sol by mixing a metal alkoxide in a non-alcoholic medium comprising water and an acid catalyst and exposing the mixture to ultrasonic energy, the mixture having a pH not greater than about 2; (b) removing the ultrasonic energy and raising the pH of the sol to about 5 to 7 by the addition of a buffering agent; (c) adding an active biological material to the buffered sol; (d) forming a gel and allowing the gel to age; and (e) allowing at least a portion of the water in the gel to evaporate so that external dimensions of the gel produced in step (d) are reduced and the active biological material is held within the structure after evaporation.

Claim 15

Dependent Claim 27 words

The porous transparent sol-gel glass of claim 12 wherein a pre-buffer aging step is added after exposing the mixture to ultrasound but prior to buffering the mixture.

Claim 16

Dependent Claim 18 words

The porous transparent glass of claim 12 wherein the gel is aged for at least about ten days.

Claim 17

Dependent Claim 19 words

The porous transparent glass of claim 14 wherein the aged gel is dried for at least about ten days.

Claim 18

Dependent Claim 15 words

The porous transparent glass of claim 12 wherein the active biological material is a protein.

Claim 19

Dependent Claim 40 words

The porous transparent glass of claim 12 wherein the active biological material is selected from the group consisting of nuclease, protease, oxidase, esterase, isomerase, metal and metal ion binders, bicarbonate binders, free radical inhibitors, reversible oxygen binders and combinations thereof.

Claim 20

Dependent Claim 49 words

The porous transparent glass of claim 12 wherein the active biological material is selected from the group consisting of RNase A, RNase T1, protease k, chymotrypsin, alcohol oxidase, glucose oxidase, acetylcholine esterase, phosphodiesterase II, aldolase, glucose isomerase, hemoglobin, myoglobin, cytochrome c, aequorin, transferase, urease, superoxide dismutase and combinations thereof.

Claim 21

Dependent Claim 34 words

The porous transparent sol-gel glass of claim 12 wherein the volume of the structure produced by evaporation is reduced to about twelve percent (12%) of the volume of the gel produced in step (d).

Claim 22

Dependent Claim 20 words

The porous transparent glass of claim 12 wherein the gel is aged for about 2 days to about 21 days.

Claim 23

Dependent Claim 20 words

The porous glass of claim 12 wherein the aged gel is dried for about 8 days to about 60 days.

Claim 24

Dependent Claim 52 words

A porous, transparent sol-gel glass having an apparent density of 1.2 g/cc, a specific surface area of about 400 to 800 m 2 /g, a median pore radius of about 15 Angstroms and a maximum pore radius of about 100 Angstroms, the porous, transparent glass having an active biological material entrapped therein.

Claim 25

Dependent Claim 52 words

A porous, transparent sol-gel glass having an apparent density of 1.2 g/cc, a specific surface area of about 400 to 800 m 2 /g, a median pore radius of about 15 Angstroms and a maximum pore radius of about 100 Angstroms, the porous, transparent glass having an active biological material entrapped therein.

Claim 26

Dependent Claim 41 words

The porous, transparent sol-gel glass of claim 22 wherein the active biological material is selected from the group consisting of nuclease, protease, oxidase, esterase, isomerase, metal and metal ion binders, bicarbonate binders, free radical inhibitors, reversible oxygen binders and combinations thereof.

Claim 27

Dependent Claim 50 words

The porous transparent sol-gel glass of claim 22 wherein the active biological material is selected from the group consisting of RNase A, RNase T1, protease k, chymotrypsin, alcohol oxidase, glucose oxidase, acetylcholine esterase, phosphodiesterase II, aldolase, glucose isomerase, hemoglobin, myoglobin, cytochrome c, aequorin, transferase, urease, superoxide dismutase and combinations thereof.

Claim 28

Independent Claim 195 words

A method for the qualitative or quantitative detection of a substance which reacts with or whose reaction is catalyzed by an active biological material which comprises: (1) The production of a porous, transparent sol-gel glass containing an active biological material entrapped therein comprising: (a) forming a single phase sol by mixing a metal alkoxide in a non-alcoholic medium comprising water and an acid catalyst in a container exposed to ultrasonic energy, the mixture having a pH not greater than about 2; (b) removing the ultrasonic energy and raising the pH of the sol to about 5 to 7 by the addition of a buffering agent; (c) adding an active biological material to the buffered sol; (d) forming a gel and allowing the gel to age; and (e) allowing at least a portion of the water in the gel to evaporate causing the gel to shrink and the active biological material to be trapped in the porous glass. (2) Brining the porous, transparent glass containing the active biological material into contact with an aqueous solution of the substance; and (3) Observing the change in optical characteristics of the porous, transparent glass containing an active biological material.

Claim 29

Independent Claim 195 words

A method for the qualitative or quantitative detection of a substance which reacts with or whose reaction is catalyzed by an active biological material which comprises: (1) The production of a porous, transparent sol-gel glass containing an active biological material entrapped therein comprising: (a) forming a single phase sol by mixing a metal alkoxide in a non-alcoholic medium comprising water and an acid catalyst in a container exposed to ultrasonic energy, the mixture having a pH not greater than about 2; (b) removing the ultrasonic energy and raising the pH of the sol to about 5 to 7 by the addition of a buffering agent; (c) adding an active biological material to the buffered sol; (d) forming a gel and allowing the gel to age; and (e) allowing at least a portion of the water in the gel to evaporate causing the gel to shrink and the active biological material to be trapped in the porous glass. (2) Brining the porous, transparent glass containing the active biological material into contact with an aqueous solution of the substance; and (3) Observing the change in optical characteristics of the porous, transparent glass containing an active biological material.

Claim 30

Dependent Claim 16 words

The method of claim 25 wherein the change in optical characteristics is observed using spectroscopic techniques.

Claim 31

Dependent Claim 27 words

The method of claim 26 wherein the spectroscopic techniques are selected from the group consisting of UV, IR, visible light, fluorescence, luminescence, absorption, emission and reflection techniques.

Claim 32

Dependent Claim 24 words

The method of claim 25 wherein a pre-buffer aging step is added after exposing the mixture to ultrasound but prior to buffering the mixture.

Claim 33

Dependent Claim 16 words

The method of claim 25 wherein the gel is aged for at least about ten days

Claim 34

Dependent Claim 17 words

The method of claim 29 wherein the aged gel is dried for at least about ten days.

Claim 35

Dependent Claim 13 words

The method of claim 25 wherein the active biological material is a protein.

Claim 36

Dependent Claim 38 words

The method of claim 25 wherein the active biological material is selected from the group consisting of nuclease, protease, oxidase, esterase, isomerase, metal and metal ion binders, bicarbonate binders, free radical inhibitors, reversible oxygen binders and combinations thereof.

Claim 37

Dependent Claim 45 words

The method of claim 25 wherein the active biological material is selected from the group consisting of RNase A, RNase T1, chymotrypsin, alcohol oxidase, glucose oxidase, acetylcholine esterase, phosphodiesterase II, aldolase, glucose isomerase, hemoglobin, myoglobin, cytochrome c, aequorin, transferase, urease, superoxide dismutase and combinations thereof.

Claim 38

Dependent Claim 28 words

The method of claim 25 wherein the porous transparent sol-gel glass is prepared in the form of a film with a thickness of greater than about 1000 Angstroms.

Claim 39

Dependent Claim 28 words

The method of claim 25 wherein the porous transparent sol-gel glass is prepared in the form of a monolith with a smallest dimension less than about 0.5 centimeters.

Claim 40

Dependent Claim 33 words

The method of claim 26 wherein the porous transparent sol-gel glass is prepared in the form of a three dimensional structure having a shortest dimension between about 1000 Angstroms and about 0.5 centimeters.

Claim 41

Dependent Claim 33 words

The method of claim 25 wherein the porous glass formed in step (1) (e) has a volume of about twelve percent (12%) of the volume of the gel formed in step (1) (d).

Claim 42

Dependent Claim 18 words

The method of claim 25 wherein the gel is aged for about 2 days to about 21 days.

Claim 43

Dependent Claim 19 words

The method of claim 25 wherein the aged gel is dried for about 8 days to about 60 days.

Claim 44

Dependent Claim 104 words

A process for the production of a porous, transparent aged gel containing an alcohol sensitive active biological material entrapped therein comprising: (a) forming a single phase sol by mixing a metal alkoxide in a non-alcoholic medium comprising water and an acid catalyst in a container exposed to ultrasonic energy, the mixture having a pH not greater than about 2; (b) removing the ultrasonic energy and raising the pH of the sol to about 5 to 7 by the addition of a buffering agent; (c) adding an active biological material to the buffered sol; and (d) forming a gel and allowing the gel to age.

Claim 45

Dependent Claim 104 words

A process for the production of a porous, transparent aged gel containing an alcohol sensitive active biological material entrapped therein comprising: (a) forming a single phase sol by mixing a metal alkoxide in a non-alcoholic medium comprising water and an acid catalyst in a container exposed to ultrasonic energy, the mixture having a pH not greater than about 2; (b) removing the ultrasonic energy and raising the pH of the sol to about 5 to 7 by the addition of a buffering agent; (c) adding an active biological material to the buffered sol; and (d) forming a gel and allowing the gel to age.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1996-04-05	1996-10-05	1997-04-06	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	2000-04-05	2000-10-05	2001-04-06	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2004-04-05	2004-10-05	2005-04-06	$7700.00	Window Closed / Lapsed

Sol-gel encapsulated enzyme

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