# US 10,309,939 B2 · Chromatography systems and methods using them

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- Number: US 10,309,939 B2
- Document ID: US10309939B2
- Status: Granted
- Kind: B2
- Application number: 15/209,427
- Filed: 2016-07-13
- Published: 2017-04-13
- Granted: 2019-06-04
- Earliest claimed: 2008-05-27
- Assignees: PerkinElmer Health Sciences, Inc.
- Applicants: Perkinelmer Health Sciences, Inc.
- Inventors: Andrew Tipler
- Web page: https://patentgrep.com/patent/US10309939B2

## CPC

- G01N 30/32: of pressure or speed (G01N30/36 takes precedence)
- G01N 30/20: using a sampling valve
- G01N 30/28: Control of physical parameters of the fluid carrier
- G01N 30/466: {with separation columns in parallel}
- G01N 30/6095: {Micromachined or nanomachined, e.g. micro- or nanosize}
- G01N 30/7206: {interfaced to gas chromatograph (interfaces in general for introducing or extracting samples to be analysed with specially adapted mass spectrometer, see H01J49/04)}
- G01N 30/468: {involving switching between different column configurations}
- G01N 30/72: Mass spectrometers {(mass spectrometers per se H01J49/00)}
- G01N 2030/025: {Gas chromatography}
- G01N 2030/208: {with more than one cavity}
- G01N 2030/324: {speed, flow rate}
- G01N 2030/328: {valves, e.g. check valves of pumps}
- Y10T 29/49: Method of mechanical manufacture
- Y10T 137/0318: Processes
- G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q)
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

Certain embodiments described herein are directed to chromatography systems that include a microfluidic device. The microfluidic device can be fluidically coupled to a switching valve to provide for selective control of fluid flow in the chromatography system. In some examples, the microfluidic device may include a charging chamber, a bypass restrictor or other features that can provide for added control of the fluid flow in the system. Methods of using the devices and methods of calculating lengths and diameters to provide a desired flow rate are also described.

## Claims

### Claim 1

A system for modulating flow of a fluid in a chromatography system, the system comprising:
a microfluidic device fluidically coupled to a switching valve, in which the microfluidic device comprises a first charging chamber and a second charging chamber; and
a detector fluidically coupled to a first outlet of the microfluidic device,
wherein the switching valve is configured to actuate between a first position and a second position, wherein the first position is configured to permit fluid flow from a modulating gas source to the first charging chamber of the microfluidic device to provide column effluent from the first charging chamber to the detector fluidically coupled to the microfluidic device, and wherein the second position is configured to permit fluid flow from the modulating gas source to the second charging chamber of the microfluidic device to provide column effluent from the second charging chamber to the detector fluidically coupled to the microfluidic device.

### Claim 2 (depends on 1)

The system of claim 1, in which the switching valve is a 3-way solenoid valve that is actuated at a frequency of about 10 Hz to about 100 Hz.

### Claim 3 (depends on 1)

The system of claim 1, further comprising a restrictor between the first outlet of the microfluidic device and the detector, in which the restrictor is configured to balance pressure in system.

### Claim 4 (depends on 3)

The system of claim 3, in which a restrictor length of the restrictor is calculated using the following equation
L
r
=
[
π
×
T
a
×
d
r
4
256
×
F
a
×
p
a
×
(
p
i
2
-
p
or
2
)
-
T
r
⁢
⁢
2
×
η
r
⁢
⁢
2
×
L
r
⁢
⁢
2
]
T
r
⁢
⁢
1
×
η
r
⁢
⁢
1
+
L
r
⁢
⁢
2
where Lr1 is length of the restrictor inside the oven, Lr2 is length of the restrictor inside the detector, ηr1 is viscosity of carrier gas at temperature of an oven, ηr2 is viscosity of carrier gas at a detector temperature, Tr1 is absolute temperature of the oven, Tr2 is the absolute temperature of the detector, pi is inlet pressure, por is outlet pressure and Fa is flow rate.

### Claim 5 (depends on 1)

The system of claim 1, further comprising a second detector fluidically coupled to a second outlet of the microfluidic device.

### Claim 6 (depends on 5)

The system of claim 5, further comprising a first restrictor between the first outlet and the detector and a second restrictor between second outlet and the second detector.

### Claim 7 (depends on 1)

The system of claim 1, further comprising an internal restrictor within the microfluidic device.

### Claim 8 (depends on 7)

The system of claim 7, in which an internal diameter of the internal restrictor is calculated using the following equation
d
r
=
256
·
L
·
p
a
·
η
b
·
π
4
where dr is the internal diameter of the restrictor, L is restrictor length, pa is absolute pressure, η is viscosity of a carrier gas and b is a constant.

### Claim 9 (depends on 1)

The system of claim 1, in which the microfluidic device comprises an internal microchannel comprising a variable diameter at different portions of the internal microchannel.

### Claim 10 (depends on 1)

The system of claim 1, in which the switching valve comprises a laminated membrane.

### Claim 11 (depends on 1)

The system of claim 1, in which the switching valve is a 3-way solenoid valve and the microfluidic device is configured as a laminated wafer comprising stainless steel plates.

### Claim 12 (depends on 1)

The system of claim 1, in which the microfluidic device is configured as a laminated wafer.

### Claim 13 (depends on 12)

The system of claim 12, in which the first charging chamber and the second charging chamber are formed from laminating different layers of the laminated wafer to each other.

### Claim 14 (depends on 12)

The system of claim 12, in which the laminated wafer comprises stainless steel plates.

### Claim 15 (depends on 14)

The system of claim 14, in which the laminated wafer comprises a plurality of ports each connected to each other through an internal microfluidic channel.

### Claim 16 (depends on 15)

The system of claim 15, in which the internal microfluidic channel comprises an internal bypass restrictor.