US4743377A — Packing material for liquid chromatography

Claim 1

Independent Claim 194 words

A process for the manufacture of a packing material for liquid chromatography, comprising particles having a silicone polymer film coated on substantially the entire surface thereof, said process comprising the steps of: (a) bringing at least one silicone compound having the general formula (I): (R.sup.1 HSiO).sub.a (R.sup.2 R.sup.3 SiO).sub.b (R.sup.4 R.sup.5 R.sup.6 SiO.sub.1/2).sub.c (I) wherein R 1 , R 2 , and R 3 represent, independently, a hydrocarbon residue having 1 to 10 carbon atoms, which may be substituted with at least one halogen atom, R 4 , R 5 , and R 6 represent, independently, hydrogen or a hyrocarbon residue baving 1 to 10 carbon atoms, which may be substituted with at least one halogen atom, a is zero or an integer of 1 or more, b is zero or an integer of 1 or more, c is zero or 2, and a+b+c is 3 to 300, with the proviso that, when c is zero, b is an integer of 1 or more, into contact with particles, whereby the silicone compound is polymerized on substantially the entire surface of the particles, and (b) crosslinking unreacted Si--H groups in the presence of a catalyst.

Claim 2

Dependent Claim 194 words

A process for the manufacture of a packing material for liquid chromatography, comprising particles having a silicone polymer film coated on substantially the entire surface thereof, said process comprising the steps of: (a) bringing at least one silicone compound having the general formula (I): (R.sup.1 HSiO).sub.a (R.sup.2 R.sup.3 SiO).sub.b (R.sup.4 R.sup.5 R.sup.6 SiO.sub.1/2).sub.c (I) wherein R 1 , R 2 , and R 3 represent, independently, a hydrocarbon residue having 1 to 10 carbon atoms, which may be substituted with at least one halogen atom, R 4 , R 5 , and R 6 represent, independently, hydrogen or a hyrocarbon residue baving 1 to 10 carbon atoms, which may be substituted with at least one halogen atom, a is zero or an integer of 1 or more, b is zero or an integer of 1 or more, c is zero or 2, and a+b+c is 3 to 300, with the proviso that, when c is zero, b is an integer of 1 or more, into contact with particles, whereby the silicone compound is polymerized on substantially the entire surface of the particles, and (b) crosslinking unreacted Si--H groups in the presence of a catalyst.

Claim 3

Dependent Claim 30 words

A process according to claim 1, further comprising the step of: (c) trimethylsilylating Si--OH groups formed slightly in said step (b) with an agent capable of providing a trimethylsilyl group.

Claim 4

Dependent Claim 51 words

A process according to claim 1, wherein the silicone compound having the general formula (I) is brought into contact with particles having an average particle size of 3-1000 μm and pores of 30-1000 Å, selected from a group consisting of silica gel, alumina, glass bead, zeolite, hydroxyapatite, graphite and composite particles.

Claim 5

Dependent Claim 29 words

A process according to claim 1, wherein, in step (a), a silcone compound having the general formula (I) in a vapor phase is brought into contact with the particles.

Claim 6

Dependent Claim 22 words

A process according to claim 1, wherein, in step (b), an alkaline, alkyl metal or alkylamine catalyst is used as the catalyst.

Claim 7

Dependent Claim 29 words

A process according to claim 1, wherein the resulting packing material comprises particles having the silicone polymer film coated thereon of a thickness of 3 Å to 30 Å.

Claim 8

Dependent Claim 203 words

A process for the manufacture of a packing material for liquid chromatography, comprising particles having a silicone polymer film coated on substantially the entire surface thereof, said process comprising the steps of: (a) bringing at least one silicone compound having the general formula (I): (R.sup.1 HSiO).sub.a (R.sup.2 R.sup.3 SiO).sub.b (R.sup.4 R.sup.5 R.sup.6 SiO.sub.1/2).sub.c (I) wherein R 1 , R 2 , and R 3 represent, independently, a hydrocarbon residue having 1 to 10 carbon atoms, which may be substituted with at least one halogen atom, R 4 , R 5 , and R 6 represent, independently, hydrogen or a hydrocarbon residue having 1 to 10 carbon atoms, which may be substituted with at least one halogen atom, a is zero or an integer of 1 or more, b is zero or an integer of 1 or more, c is zero or 2, and a+b+c is 3 to 300, with the proviso that, when c is zero, b is an integer of 1 or more, into contact with particles, whereby the silicone compound is polymerized on substantially the entire surface of the particles, and (b) carrying out an addition reaction of a vinyl compound having up to 40 carbon atoms to unreacted Si--H groups.

Claim 9

Dependent Claim 203 words

A process for the manufacture of a packing material for liquid chromatography, comprising particles having a silicone polymer film coated on substantially the entire surface thereof, said process comprising the steps of: (a) bringing at least one silicone compound having the general formula (I): (R.sup.1 HSiO).sub.a (R.sup.2 R.sup.3 SiO).sub.b (R.sup.4 R.sup.5 R.sup.6 SiO.sub.1/2).sub.c (I) wherein R 1 , R 2 , and R 3 represent, independently, a hydrocarbon residue having 1 to 10 carbon atoms, which may be substituted with at least one halogen atom, R 4 , R 5 , and R 6 represent, independently, hydrogen or a hydrocarbon residue having 1 to 10 carbon atoms, which may be substituted with at least one halogen atom, a is zero or an integer of 1 or more, b is zero or an integer of 1 or more, c is zero or 2, and a+b+c is 3 to 300, with the proviso that, when c is zero, b is an integer of 1 or more, into contact with particles, whereby the silicone compound is polymerized on substantially the entire surface of the particles, and (b) carrying out an addition reaction of a vinyl compound having up to 40 carbon atoms to unreacted Si--H groups.

Claim 10

Dependent Claim 22 words

A process according to claim 7, further comprising the step of: (c) crosslinking unreacted Si--H groups in the presence of a catalyst.

Claim 11

Dependent Claim 30 words

A process according to claim 8, further comprising the step of: (d) trimethylsilylating Si--OH groups formed slightly in said step (c) with an agent capable of providing a trimethylsilyl group.

Claim 12

Dependent Claim 22 words

A process according to claim 8, wherein, in step (c), an alkaline, alkyl metal or alkylamine catalyst is used as the catalyst.

Claim 13

Dependent Claim 52 words

A process according to claim 7, wherein the silicone compound having the general formula (I) is brought into contact with particles having an average particle size of 3-1000 um and pores of 30-1000 Å, and selected from a group consisting of silica gel, alumina, glass bead, zeolite, hydroxyapatite, graphite and composite particles.

Claim 14

Dependent Claim 29 words

A process according to claim 7, wherein, the step (a), a silicone compound having the general formula (I) in a vapor phase is brought into contact with the particles.

Claim 15

Dependent Claim 117 words

A process according to claim 7, wherein, in the step (b), a vinyl compound having the general formula (III): R.sup.8 --CH═CH--R.sup.9 (III) wherein R 8 and R 9 represent, independently, a hydrogen atom, an alkyl group having 1 to 40 carbon atoms, a cycloalkyl or cycloalkenyl group having 4 to 8 carbon atoms, or an aryl group which may be substituted by one or more alkyl groups having 1 to 20 carbon atoms, and wherein said alkyl, cycloalkyl or cycloalkenyl group, or aryl group optionally substituted by one or more alkyl groups may be substituted by one or more halogen atoms, hydroxyl, carboxyl, amino, cyano, alkoxycarbonyl, aryloxycarbonyl and/or sulfonic acid groups, is used as the vinyl compound.

Claim 16

Independent Claim 217 words

A method for making a liquid chromatographic separation of components contained in a liquid sample which comprises contacting the liquid sample with a chromatographic column containing a packing material comprising particles having a silicone polymer film coated on substantially the entire surface thereof, said packing material being produced by a process comprising the steps of: (a) bringing at least one silicone compound having the general formula (I): (R.sup.1 HSiO).sub.a (R.sup.2 R.sup.3 SiO).sub.b (R.sup.4 R.sup.5 R.sup.6 SiO.sub.1/2).sub.c (I) wherein R 1 , R 2 , and R 3 represent, indepently, a hydrocarbon residue having 1 to 10 carbon atoms, which may be substituted with at least one halogen atom, R 4 , R 5 , and R 6 represent, independently, hydrogen or a hydrocarbon residue having 1 to 10 carbon atoms, which may be substituted with at least one halogen atom, a is zero or an integer of 1 or more, b is zero or an integer of 1 or more, c is zero or 2, and a+b+c is 3 to 300, with the proviso that, when c is zero, b is an integer of 1 or more, into contact with particles, whereby the silicone compound is polymerized on substantially the entire surface of the particles, and (b) crosslinking unreacted Si--H groups in the presence of a catalyst.

Claim 17

Independent Claim 217 words

A method for making a liquid chromatographic separation of components contained in a liquid sample which comprises contacting the liquid sample with a chromatographic column containing a packing material comprising particles having a silicone polymer film coated on substantially the entire surface thereof, said packing material being produced by a process comprising the steps of: (a) bringing at least one silicone compound having the general formula (I): (R.sup.1 HSiO).sub.a (R.sup.2 R.sup.3 SiO).sub.b (R.sup.4 R.sup.5 R.sup.6 SiO.sub.1/2).sub.c (I) wherein R 1 , R 2 , and R 3 represent, indepently, a hydrocarbon residue having 1 to 10 carbon atoms, which may be substituted with at least one halogen atom, R 4 , R 5 , and R 6 represent, independently, hydrogen or a hydrocarbon residue having 1 to 10 carbon atoms, which may be substituted with at least one halogen atom, a is zero or an integer of 1 or more, b is zero or an integer of 1 or more, c is zero or 2, and a+b+c is 3 to 300, with the proviso that, when c is zero, b is an integer of 1 or more, into contact with particles, whereby the silicone compound is polymerized on substantially the entire surface of the particles, and (b) crosslinking unreacted Si--H groups in the presence of a catalyst.

Claim 18

Dependent Claim 34 words

A method according to claim 14, wherein the above process further comprises the step of: (c) trimethylsilylating Si--OH groups formed slightly in said step (b) with an agent capable of providing a trimethylsilyl group.

Claim 19

Independent Claim 226 words

A method for making a liquid chromatographic separation of components contained in a liquid sample which comprises contacting the liquid sample with a chromatographic column containing a packing material comprising particles having a silicone polymer film coated on substantially the entire surface thereof, said packing material being produced by a process comprising the steps of: (a) bringing at least one silicone compound having the general formula (I): (R.sup.1 HSiO).sub.a (R.sup.2 R.sup.3 SiO).sub.b (R.sup.4 R.sup.5 R.sup.6 SiO.sub.1/2).sub.c (I) wherein R 1 , R 2 , and R 3 represent, independently, a hydrocarbon residue having 1 to 10 carbon atoms, which may be substituted with at least one halogen atom, R 4 , R 5 , and R 6 represent, independently, hydrogen or a hydrocarbon residue having 1 to 10 carbon atoms, which may be substituted with at least one halogen atom, a is zero or an integer of 1 or more, b is zero or an integer of 1 or more, c is zero or 2, and a+b+c is 3 to 300, with the proviso that, when c is zero, b is an integer of 1 or more, into contact with particles, whereby the silicone compound is polymerized on substantially the entire surface of the particles, and (b) carrying out an addition reaction of a vinyl compound having up to 40 carbon atoms to unreacted Si--H groups.

Claim 20

Independent Claim 226 words

A method for making a liquid chromatographic separation of components contained in a liquid sample which comprises contacting the liquid sample with a chromatographic column containing a packing material comprising particles having a silicone polymer film coated on substantially the entire surface thereof, said packing material being produced by a process comprising the steps of: (a) bringing at least one silicone compound having the general formula (I): (R.sup.1 HSiO).sub.a (R.sup.2 R.sup.3 SiO).sub.b (R.sup.4 R.sup.5 R.sup.6 SiO.sub.1/2).sub.c (I) wherein R 1 , R 2 , and R 3 represent, independently, a hydrocarbon residue having 1 to 10 carbon atoms, which may be substituted with at least one halogen atom, R 4 , R 5 , and R 6 represent, independently, hydrogen or a hydrocarbon residue having 1 to 10 carbon atoms, which may be substituted with at least one halogen atom, a is zero or an integer of 1 or more, b is zero or an integer of 1 or more, c is zero or 2, and a+b+c is 3 to 300, with the proviso that, when c is zero, b is an integer of 1 or more, into contact with particles, whereby the silicone compound is polymerized on substantially the entire surface of the particles, and (b) carrying out an addition reaction of a vinyl compound having up to 40 carbon atoms to unreacted Si--H groups.

Claim 21

Dependent Claim 26 words

A method according to claim 16, wherein the above process further comprises the step of: (c) crosslinking unreacted Si--H group in the presence of a catalyst.

Claim 22

Dependent Claim 34 words

A method according to claim 17, wherein the above process further comprises the step of: (d) trimethylsilylating Si--OH groups formed slightly in said step (c) with an agent capable of providing a trimethylsilyl group.

Claim 23

Dependent Claim 158 words

A process for the manufacture of a packing material for reversed phase liquid chromatography, comprising particles having a silicone polymer film coated on substantially the entire surface thereof, said process comprising the steps of: (a) bringing a cyclic silicone compound having the general formula (VI): ##STR18## wherein R 1 represents a lower alkyl or aryl group, and a" is an integer of 3 to 100, into contact with particles, whereby the silicone compound is polymerized on substantially the entire surface of the particles, and (b) crosslinking unreacted Si--H groups in the presence of a catalyst, thereby producing the particles having the silicone polymer coated on substantially the entire surface thereof, said silicone polymer having the general formula (II): [(R.sup.1 SiO.sub.3/2).sub.x (R.sup.1 HSiO).sub.y ].sub.t (II) wherein R 1 has the meaning as given above, t is an integer for making a molecular weight of the polymer more than 150,000, and x and y have the following relationships: x+y=1, and

Claim 24

Dependent Claim 158 words

A process for the manufacture of a packing material for reversed phase liquid chromatography, comprising particles having a silicone polymer film coated on substantially the entire surface thereof, said process comprising the steps of: (a) bringing a cyclic silicone compound having the general formula (VI): ##STR18## wherein R 1 represents a lower alkyl or aryl group, and a" is an integer of 3 to 100, into contact with particles, whereby the silicone compound is polymerized on substantially the entire surface of the particles, and (b) crosslinking unreacted Si--H groups in the presence of a catalyst, thereby producing the particles having the silicone polymer coated on substantially the entire surface thereof, said silicone polymer having the general formula (II): [(R.sup.1 SiO.sub.3/2).sub.x (R.sup.1 HSiO).sub.y ].sub.t (II) wherein R 1 has the meaning as given above, t is an integer for making a molecular weight of the polymer more than 150,000, and x and y have the following relationships: x+y=1, and

Claim 25

Dependent Claim 1 words

6≦x<1.

Claim 26

Dependent Claim 1 words

6≦x<1.

Claim 27

Dependent Claim 34 words

A process according to claim 19, wherein the silicone compound having the general formula (VI) is brought into contact with particles selected from a group consisting of silica gel, alumina, glass bead and zeolite.

Claim 28

Dependent Claim 24 words

A process according to claim 20, wherein the silica gel having a particle size of 3-500 μm and pores of 50-500 Å is used.

Claim 29

Dependent Claim 29 words

A process according to claim 19, wherein, in step (a), a silicone compound having the general formula (VI) in a vapor phase is brought into contact with the particles.

Claim 30

Dependent Claim 21 words

A process according to claim 19, wherein, in step (b), an alkaline or alkyl metal catalyst is used as the catalyst.

Claim 31

Dependent Claim 251 words

A process for the manufacture of a packing material for reversed phase liquid chromatography, comprising particles having a silicone polymer film coated on substantially the entire surface thereof, said process comprising the steps of: (a) bringing a cyclic silicone compound having the general formula (VI): ##STR19## wherein R 1 represents a lower alkyl or aryl group, and a" is an integer of 3 to 100, into contact with particles, whereby the silicone compound is polymerized on substantially the entire surface of the particles, and (b) carrying out an addition reaction of a vinyl compound having the general formula (III): R.sup.8 --CH═CH═R.sup.9 (III) wherein R 8 represents hydrogen or alkyl group having 1 to 20 carbon atoms and R 9 represents hydrogen; both of R 8 and R 9 represent alkyl group having 1 to 20 carbon atoms; or R 8 represents phenyl group substituted with alkyl group having 1 to 20 carbon atoms and R 9 represents hydrogen; to unreacted Si--H groups, thereby producing the particles having the silicone polymer film coated on substantially the entire surface thereof, said silicone polymer having the general formula (IV): ](R.sup.1 SiO.sub.3/2).sub.x',(R.sup.1 HSiO).sub.y' (R.sup.1 R.sup.7 SiO).sub.z ].sub.u (IV) wherein R 1 has the meaning as given above, R 7 represents a residue of the addition reaction of the vinyl compound of the general formula (III), u is an integer for making a molecular weight of the polymer more than 150,000, and x', y' and z have the following relationships: x'+y'+z=1, < x'≦0.5 0<y'≦0.4, and 0.5≦z<1.0.

Claim 32

Dependent Claim 251 words

A process for the manufacture of a packing material for reversed phase liquid chromatography, comprising particles having a silicone polymer film coated on substantially the entire surface thereof, said process comprising the steps of: (a) bringing a cyclic silicone compound having the general formula (VI): ##STR19## wherein R 1 represents a lower alkyl or aryl group, and a" is an integer of 3 to 100, into contact with particles, whereby the silicone compound is polymerized on substantially the entire surface of the particles, and (b) carrying out an addition reaction of a vinyl compound having the general formula (III): R.sup.8 --CH═CH═R.sup.9 (III) wherein R 8 represents hydrogen or alkyl group having 1 to 20 carbon atoms and R 9 represents hydrogen; both of R 8 and R 9 represent alkyl group having 1 to 20 carbon atoms; or R 8 represents phenyl group substituted with alkyl group having 1 to 20 carbon atoms and R 9 represents hydrogen; to unreacted Si--H groups, thereby producing the particles having the silicone polymer film coated on substantially the entire surface thereof, said silicone polymer having the general formula (IV): ](R.sup.1 SiO.sub.3/2).sub.x',(R.sup.1 HSiO).sub.y' (R.sup.1 R.sup.7 SiO).sub.z ].sub.u (IV) wherein R 1 has the meaning as given above, R 7 represents a residue of the addition reaction of the vinyl compound of the general formula (III), u is an integer for making a molecular weight of the polymer more than 150,000, and x', y' and z have the following relationships: x'+y'+z=1, < x'≦0.5 0<y'≦0.4, and 0.5≦z<1.0.

Claim 33

Dependent Claim 34 words

A process according to claim 24 wherein the silicone compound having the general formula (VI) is brought into contact with particles selected from a group consisting of silica gel, alumina, glass bead and zeolite.

Claim 34

Dependent Claim 24 words

A process according to claim 25, wherein the silica gel having a particle size of 3-500 um and pores of 50-500 Å is used.

Claim 35

Dependent Claim 29 words

A process according to claim 24, wherein, in step (a), a silicone compound having the general formula (VI) in a vapor phase is brought into contact with the particles.

Claim 36

Independent Claim 182 words

A method for making a reversed phase liquid chromatigraphic separation of components contained in a liquid sample which comprises contacting the liquid sample with a chromatographic column containing a packing material comprising particles having a silicone polymer film coated on substantially the entire surface thereof, said packing material being produced by a process comprising the steps of: (a) bringing a cyclic silicone compound having the general formula (VI); ##STR20## wherein R 1 represents a lower alkyl or aryl group, and a" is an integer of 3 to 100, into contact with particles, whereby the silicone compound is polymerized on substantially the entire surface of the particles, and (b) crosslinked unreacted Si--H groups in the presence of a catalyst, thereby producing the particles having the silicone polymer film coated on substantially the entire surface thereof, said silicone polymer having the general formula (II): [(R.sup.1 SiO.sub.(3/2)).sub.x (R.sup.1 HSiO).sub.y ].sub.t (II) wherein R 1 has the meaning as given above, t is an integer for making a molecular weight of the polymer more than 150,000, and x and y have the following relationships: x+y=1, and

Claim 37

Independent Claim 182 words

A method for making a reversed phase liquid chromatigraphic separation of components contained in a liquid sample which comprises contacting the liquid sample with a chromatographic column containing a packing material comprising particles having a silicone polymer film coated on substantially the entire surface thereof, said packing material being produced by a process comprising the steps of: (a) bringing a cyclic silicone compound having the general formula (VI); ##STR20## wherein R 1 represents a lower alkyl or aryl group, and a" is an integer of 3 to 100, into contact with particles, whereby the silicone compound is polymerized on substantially the entire surface of the particles, and (b) crosslinked unreacted Si--H groups in the presence of a catalyst, thereby producing the particles having the silicone polymer film coated on substantially the entire surface thereof, said silicone polymer having the general formula (II): [(R.sup.1 SiO.sub.(3/2)).sub.x (R.sup.1 HSiO).sub.y ].sub.t (II) wherein R 1 has the meaning as given above, t is an integer for making a molecular weight of the polymer more than 150,000, and x and y have the following relationships: x+y=1, and

Claim 38

Dependent Claim 1 words

6≦x<1.

Claim 39

Dependent Claim 1 words

6≦x<1.

Claim 40

Independent Claim 268 words

A method for making a reversed phase liquid chromatographic separation of components contained in a liquid sample which comprises contacting the liquid sample with a chromatographic column containing a packing material comprising particles having a silicone polymer film coated substantially the entire surface thereof, said process comprising the steps of: (a) bringing a cyclic silicone compound having the general formula (VI): ##STR21## wherein R 1 represents a lower alkyl or aryl group, and a" is an integer of 3 to 100, into contact with particles, whereby the silicone compound is polymerized on substantially the entire surface of the particles, and (b) carrying out an addition reaction of a vinyl compound having the general formula (III): R.sup.8 --CH═CH═R.sup.9 (III) wherein R 8 represents hydrogen or alkyl group having 1 to 20 carbon atoms and R 9 represents hydrogen, both of R 8 and R 9 represents alkyl group having 1 to 20 carbon atoms, or R 8 represents phenyl group substituted with alkyl group having 1 to 20 carbon atoms and R 9 represents hydrogen; to unreacted Si--H groups, thereby producing the particles having the silicone polymer film coated on substantially the entire surface thereof, said silicone polymer having the general formula (IV): [(R.sup.1 SiO.sub.(3/2)).sub.x' (R.sup.1 HSiO).sub.y' (R.sup.1 R.sup.7 SiO).sub.z ].sub.u (IV) wherein R 1 has the meaning as given above, R 7 represents a residue of the addition reaction of the vinyl compound of the general formula (III), u is an integer for making a molecular weight of the polymer more than 150,000, and x', y' and z have the following relationships: x'+y'+z=1, < x'≦0.5 0<y'≦0.4, and 0.5≦z<1.0.

Claim 41

Independent Claim 268 words

A method for making a reversed phase liquid chromatographic separation of components contained in a liquid sample which comprises contacting the liquid sample with a chromatographic column containing a packing material comprising particles having a silicone polymer film coated substantially the entire surface thereof, said process comprising the steps of: (a) bringing a cyclic silicone compound having the general formula (VI): ##STR21## wherein R 1 represents a lower alkyl or aryl group, and a" is an integer of 3 to 100, into contact with particles, whereby the silicone compound is polymerized on substantially the entire surface of the particles, and (b) carrying out an addition reaction of a vinyl compound having the general formula (III): R.sup.8 --CH═CH═R.sup.9 (III) wherein R 8 represents hydrogen or alkyl group having 1 to 20 carbon atoms and R 9 represents hydrogen, both of R 8 and R 9 represents alkyl group having 1 to 20 carbon atoms, or R 8 represents phenyl group substituted with alkyl group having 1 to 20 carbon atoms and R 9 represents hydrogen; to unreacted Si--H groups, thereby producing the particles having the silicone polymer film coated on substantially the entire surface thereof, said silicone polymer having the general formula (IV): [(R.sup.1 SiO.sub.(3/2)).sub.x' (R.sup.1 HSiO).sub.y' (R.sup.1 R.sup.7 SiO).sub.z ].sub.u (IV) wherein R 1 has the meaning as given above, R 7 represents a residue of the addition reaction of the vinyl compound of the general formula (III), u is an integer for making a molecular weight of the polymer more than 150,000, and x', y' and z have the following relationships: x'+y'+z=1, < x'≦0.5 0<y'≦0.4, and 0.5≦z<1.0.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1991-05-10	1991-11-09	1992-05-10	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1995-05-10	1995-11-09	1996-05-10	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1999-05-10	1999-11-09	2000-05-10	$7700.00	Window Closed / Lapsed

Packing material for liquid chromatography

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