Light scattering detector and light scattering detector sample cell

Abstract

A sample cell, a light scattering detector utilizing the sample cell, and a method of using the light scattering detector are provided. The sample cell can include a body defining a flow path extending axially therethrough. The flow path can include a cylindrical inner section interposed between a first outer section and a second outer section. The first outer section can be frusto-conical. A first end portion of the first outer section can be in direct fluid communication with the inner section and can have a cross-sectional area relatively smaller than a cross-sectional area at the second end portion of the first outer section. The body can further define an inlet in direct fluid communication with the inner section. The inlet can be configured to direct a sample into the inner section of the flow path.

Description

[Background technology]

[0001] Conventional light scattering detectors are often utilized in conjunction with chromatographic techniques to identify one or more physical attributes or characteristics of various molecules or solutes suspended in a solution. For example, light scattering detectors are often used in gel permeation chromatography (GPC) to identify one or more physical attributes or characteristics of various molecules or solutes suspended in a solution. Used in conjunction with molecular weight chromatography to determine the molecular weight and radius of gyration of various polymers In a light scattering detector, a sample or effluent containing molecules (e.g., polymers) is flowed through a sample cell from an inlet to an outlet disposed at the opposite end of the sample cell. As the effluent flows through the sample cell, it is illuminated by a collimated light beam (e.g., a laser). The interaction of the light beam with the polymers in the effluent produces scattered light. The scattered light is then measured and analyzed for various attributes, such as intensity and angle, to identify physical characteristics of the polymer.

[0002] While conventional light scattering detectors have proven effective in identifying the physical attributes of a wide variety of molecules, they are limited in their ability to analyze small molecules. For example, conventional light scattering detectors often lack the sensitivity and / or resolution to measure the Rg of molecules with a radius of gyration less than about 10 nm. In light of the above, conventional light scattering detectors often incorporate lasers with relatively high power or energy to increase the sensitivity of the detector. However, incorporating lasers with higher power is cost-prohibitive and often requires larger instruments due to the relatively large footprint of the laser. Alternatively, the volume of the sample cell in a conventional light scattering detector can be increased to increase the intensity of the scattered light. However, increasing the volume of a conventional sample cell results in excessive peak broadening. Summary of the Invention [Problem to be solved by the invention]

[0003] Therefore, there is a need for improved light scattering detectors, improved light scattering detector sample cells, and methods for increasing the sensitivity and / or resolution of light scattering detectors without increasing peak broadening. [Means for solving the problem]

[0004] This summary is intended merely to introduce a simplified overview of some aspects of one or more implementations of the present disclosure. Further scope of applicability of the present disclosure will become apparent from the detailed description provided hereinafter. This summary is not an extensive overview, and it is not intended to identify key or critical elements of the present teachings or to delineate the scope of the present disclosure. Rather, its purpose is merely to present one or more concepts in a simplified form as a prelude to the detailed description that follows.

[0005] The above and / or other aspects and advantages embodied in the present disclosure can be achieved by providing a sample cell for a light scattering detector. The sample cell can include a body defining a flow path extending axially through the body. The flow path can include a cylindrical inner section interposed between a first outer section and a second outer section. The first outer section can be frusto-conical, and a first end portion of the first outer section can be in direct fluid communication with the inner section and can have a cross-sectional area relatively smaller than a cross-sectional area at the second end portion of the first outer section. The body can further define an inlet in direct fluid communication with the inner section and configured to direct a sample into the inner section of the flow path.

[0006] In at least one implementation, the second outer section is frusto-conical, and a first end portion of the second outer section is in direct fluid communication with the inner section and has a cross-sectional area that is relatively smaller than the cross-sectional area at the second end portion of the second outer section.

[0007] In at least one implementation, the body further defines a first outlet and a second outlet extending therethrough, the first outlet and the second outlet configured to fluidly couple the second end portions of the first outer section and the second outer section to a waste line.

[0008] In at least one implementation, the body defines a first recess extending axially therethrough, the first recess being in fluid communication with the first outer section and configured to accommodate a first lens of the light scattering detector.

[0009] In at least one implementation, the body defines a second recess extending axially therethrough, the second recess being in fluid communication with the second outer section and configured to accommodate a second lens of the light scattering detector.

[0010] In at least one implementation, the body defines an aperture extending radially therethrough, the aperture being in direct fluid communication with the inner section of the flow path.

[0011] In at least one implementation, the sample cell further comprises an optically transparent material disposed within the aperture.

[0012] The above and / or other aspects and advantages embodied in the present disclosure can be achieved by providing a light scattering detector. The light scattering detector can include a laser configured to emit a light beam; and a sample cell including a body defining a flow path extending axially through the body, the flow path having a centerline aligned with the light beam, the flow path including a cylindrical inner section interposed between a first outer section and a second outer section. The first outer section is frustoconical, and a first end portion of the first outer section is in direct fluid communication with the inner section and has a cross-sectional area relatively smaller than the cross-sectional area at the second end portion of the first outer section. The body further defines an inlet in direct fluid communication with the inner section and configured to direct a sample into the inner section of the flow path. The light scattering detector can also include at least one detector operably coupled to the sample cell and configured to receive scattered light emitted from the sample cell.

[0013] In at least one implementation, the second outer section is frusto-conical, and a first end portion of the second outer section is in direct fluid communication with the inner section and has a cross-sectional area that is relatively smaller than the cross-sectional area at the second end portion of the second outer section.

[0014] In at least one implementation, the light scattering detector can include a first lens and a second lens, the first lens disposed adjacent to the first outer section of the flow path and the second lens disposed adjacent to the second outer section of the flow path.

[0015] In at least one implementation, the light scattering detector further comprises a first mirror and a first detector, the first mirror disposed proximate to the first lens and configured to reflect forward scattered light from the sample cell to the first detector.

[0016] In at least one implementation, the light scattering detector can further include a second mirror and a second detector, the second mirror disposed proximate to the second lens, and the second mirror is disposed proximate to the sample cell. The detector is configured to reflect backscattered light from the filter to a second detector.

[0017] In at least one implementation, the body defines an aperture extending radially therethrough, the aperture being in direct fluid communication with the inner section of the flow path.

[0018] In at least one implementation, the light scattering detector can further include a third detector disposed within the aperture and configured to receive right-angle scattered light from the sample cell.

[0019] In at least one implementation, the body further defines a first outlet and a second outlet extending therethrough, the first outlet and the second outlet configured to fluidly couple the second end portions of the first outer section and the second outer section to a waste line.

[0020] The above and / or other aspects and advantages embodied in the present disclosure may be achieved by providing a method of using any of the light scattering detectors disclosed herein, the method including emitting a light beam from a laser into and through a flow path of a sample cell, flowing a sample into an inner section of the flow path via an inlet of the sample cell, flowing a first portion of the sample from the inner section into and through the first frusto-conical outer section from a first end portion to a second end portion of the first frusto-conical outer section, and flowing the first portion of the sample from the second end portion of the first frusto-conical outer section via a first outlet to a waste line.

[0021] In at least one implementation, the method can further include flowing a second portion of the sample from the inner section into and through the second frusto-conical outer section from a first end portion to a second end portion of the second frusto-conical outer section, and flowing the second portion of the sample from the second end portion of the second frusto-conical outer section via a second outlet to a waste line.

[0022] In at least one implementation, the method can also include directing the forward scattered light emitted from the flow path to a first detector with a first mirror.

[0023] In at least one implementation, the method can further include directing the backscattered light emitted from the flow path to a second detector with a second mirror.

[0024] In at least one implementation, the method can include directing the orthogonally scattered light emitted from the flow path to a third detector.

[0025] Further scope of applicability of the present disclosure will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating some typical aspects of the present disclosure, are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

[0026] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate various implementations of the present disclosure. These and / or other aspects and advantages of implementations of the present disclosure will become apparent and more readily appreciated from the following description of the various implementations, taken in conjunction with the accompanying drawings. It should be noted that some details of the drawings have been simplified and are drawn to facilitate understanding of the disclosure rather than to maintain strict structural accuracy, detail, and scale. These drawings / figures are intended to be illustrative, not restrictive. do. [Brief explanation of the drawings]

[0027] [Figure 1A] FIG. 1 is a schematic diagram of an exemplary light scattering detector including an exemplary sample cell, in accordance with one or more implementations disclosed. [Figure 1B] FIG. 1B is a schematic diagram of the example sample cell of FIG. 1A, in accordance with one or more implementations disclosed. [Figure 1C] FIG. 1B is a schematic diagram of the example sample cell of FIG. 1A without analyte scattered light, according to one or more implementations disclosed. [Figure 1D] FIG. 1D is an enlarged view of the portion of the sample cell shown in the box labeled 1D in FIG. 1C, according to one or more implementations disclosed. DETAILED DESCRIPTION OF THE INVENTION

[0028] The following description of various exemplary embodiment(s) is merely exemplary in nature and is in no way intended to limit the present disclosure, its application, or uses.

[0029] As used throughout this disclosure, ranges are used as shorthand for describing each and every value within that range. It is to be appreciated and understood that the description in range format is for convenience and brevity only and should not be construed as an inflexible limitation on the scope of any embodiment or implementation disclosed herein. Accordingly, disclosed ranges should be considered to specifically disclose all possible subranges and individual numerical values ​​within that range. Accordingly, any value within that range can be selected as an endpoint of that range. For example, description of a range such as 1 to 5 should be considered to specifically disclose subranges such as 1.5 to 3, 1 to 4.5, 2 to 5, 3.1 to 5, etc., and individual numerical values ​​within that range, e.g., 1, 2, 3, 3.2, 4, 5, etc. This is true regardless of the breadth of the range.

[0030] Furthermore, all numerical values ​​are referred to as "about" or "approximately" and take into account expected experimental error and variations that would be expected by one of ordinary skill in the art. It should be understood that all numerical values ​​and ranges disclosed herein are approximate values ​​and ranges, regardless of whether "about" is used in conjunction with the numerical values ​​and ranges. It should also be understood that the term "about," as used herein in conjunction with numerical values, refers to values ​​that may be ±0.01% (inclusive), ±0.1% (inclusive), ±0.5% (inclusive), ±1% (inclusive), ±2% (inclusive), ±3% (inclusive), ±5% (inclusive), ±10% (inclusive), or ±15% (inclusive) of that numerical value. It should further be understood that when a numerical range is disclosed herein, any number falling within that range is also specifically disclosed.

[0031] All references cited herein are incorporated by reference in their entirety. In the event of a conflict between the definitions in this disclosure and those of the cited references, the present disclosure controls.

[0032] As used herein, the term or expression "sensitivity" refers to the signal-to-noise ratio. It should be recognized by those skilled in the art that increasing laser power does not necessarily improve sensitivity.

[0033] FIG. 1A shows a schematic diagram of an exemplary light scattering detector (LSD) 100 with an exemplary sample cell 102, according to one or more implementations. 00 is operatively coupled to a sample source or device 104, and 1A, the LSD 100 can be fluidly coupled to a sample source or device 104 via line 106 and configured to receive the effluent from the sample source or device 104. An exemplary sample source or device 104 can include, but is not limited to, a chromatography instrument capable of or configured to separate one or more analytes of a sample or eluent from one another. For example, the sample source or device 104 can be a liquid chromatography instrument capable of or configured to separate analytes of an eluent from one another based on their respective charge (e.g., ion exchange chromatography), size (e.g., size exclusion chromatography or gel permeation chromatography), etc. In an exemplary implementation, the LSD 100 is operably coupled to a liquid chromatography instrument configured to separate analytes from one another based on their respective size. For example, the LSD 100 is operably coupled to a liquid chromatography instrument comprising a gel permeation chromatography column.

[0034] The LSD 100 can include an exemplary sample cell 102, a collimated light beam source such as a laser 108, and one or more detectors 110, 112, 114 (three shown) operably coupled to one another. The detectors 110, 112, 114 can be any suitable detectors capable of or configured to receive analyte-scattered light. For example, any one or more of the detectors 110, 112, 114 can be photodetectors such as silicon photodetectors. The LSD 100 can include one or more lenses 116, 118, 120, 122, 124 (five shown) capable of or configured to refract, focus, attenuate, and / or collect light transmitted through the LSD 100, and one or more mirrors 126, 128 (two shown) capable of or configured to reflect or redirect light transmitted through the LSD 100.

[0035] In at least one implementation, the first lens 116 and the second lens 118 can be disposed on opposite sides of the sample cell 102 and configured to refract, focus, attenuate, and / or collect light transmitted through the lenses. In another implementation, the body 130 of the sample cell 102 can define recesses 132, 134 configured to accommodate the first lens 116 and the second lens 118. For example, as shown in FIG. 1A and further shown in detail in FIG. 1B, the body 130 of the sample cell 102 can define first and second recesses 132, 134 extending longitudinally or axially through the body 130 and configured to accommodate the first lens 116 and the second lens 118, respectively. As shown in FIGS. 1A and 1B, each of the first lens 116 and the second lens 118 can define a convex surface along a first or outer end portion 136, 138 of each lens. Although the first end portions 136, 138 of the first lens 116 and the second lens 118 are shown as defining convex surfaces, it should be appreciated that any one of the first end portions 136, 138 of each of the first lens 116 and the second lens 118 can alternatively define a flat surface. As further shown in FIG. 1A , each of the first lens 116 and the second lens 118 can define a flat surface along a second or inner end portion 140, 142 of the lens. As described further herein, the second end portions 140, 142 of each of the first lens 116 and the second lens 118 can seal and / or at least partially define a channel or flow path 144 extending through the sample cell 102.

[0036] Laser 108 may be any suitable laser capable of or configured to provide a light beam 146 having sufficient wavelength and / or power. For example, laser 108 may be a diode laser, a solid-state laser, etc. The laser 108 can be configured to emit a light beam 146 through the sample cell 102. For example, as shown in FIG. 1A, the laser 108 can be arranged or disposed around the LSD 100 such that the light beam 146 emitted from the laser 108 is transmitted through the sample cell 102. As further shown in FIG. 1A, a third lens 120 can be interposed between the sample cell 102 and the laser 108 and configured to focus the light beam 146 directed at and through the sample cell 102.

[0037] In at least one implementation, at least one of the mirrors 126, 128 can be associated with a respective detector 110, 112 and configured to reflect or redirect light (e.g., scattered light or analyte-scattered light) toward the respective detector 110, 112. For example, as shown in FIG. 1A , the first mirror 126 can be disposed proximate to the first lens 116 and configured to reflect at least a portion of the light from the first lens 116 toward the first detector 110. In another example, the second mirror 128 can be disposed proximate to the second lens 118 and / or interposed between the second lens 118 and the third lens 120 and configured to reflect at least a portion of the light from the second lens 118 toward the second detector 112. In at least one implementation, one or more lenses 122, 124 can be inserted between the first and second mirrors 126, 128 and the first and second detectors 110, 112 to focus, refract, or otherwise direct light from the mirrors 126, 128 to the detectors 110, 112. For example, as shown in FIG. 1A , a fourth lens 122 can be inserted between the first detector 110 and the first mirror 126, and a fifth lens 124 can be inserted between the second detector 112 and the second mirror 128.

[0038] In at least one implementation, at least one of the detectors 110, 112, 114 can be configured to receive light (e.g., scattered light or analyte-scattered light) from the sample cell 102 without the aid of or reflection from one of the mirrors 126, 128. For example, as shown in FIGS. 1A and 1B , a third detector 114 can be disposed adjacent to or coupled to the sample cell 102 and configured to receive light (e.g., scattered light) from the sample cell 102 at an angle of approximately 90 degrees relative to the light beam 146. As discussed further herein, an optically transparent material or a sixth lens 186 can be configured to refract or direct the scattered light toward the third detector 114.

[0039] 1A, the sample cell 102, the first lens 116, the second lens 118, and the third lens 120, and the first mirror 126 and the second mirror 128 may be arranged parallel, coaxial, or otherwise aligned with one another along the direction of the light beam 146 emitted by the laser 108. As further shown in FIG. 1A, each of the first detector 110 and the second detector 112 may be arranged or positioned to receive light (e.g., scattered light or analyte-scattered light) from the respective mirrors 126, 128 in a direction generally perpendicular to the light beam 146 emitted by the laser 108. Each of the first mirror 126 and the second mirror 128 may define a respective bore or passageway 150, 152 extending therethrough. For example, the first mirror 126 may define a bore 150 extending therethrough in a direction parallel to, coaxial with, or otherwise aligned with the light beam 146. Similarly, the second mirror 128 may define a bore 152 extending therethrough in a direction parallel to, coaxial with, or otherwise aligned with the light beam 146. The respective mirrors 126, 128 may be configured to allow the light beam 146 emitted from the laser 108 to pass through the first mirror 126 and the second mirror 128, thereby preventing the light beam 146 from reflecting toward the first detector 110 and the second detector 112. It should be appreciated that bores 150, 152 extending through 128 may be possible.

[0040] FIG. 1D illustrates an expanded view of a portion of the exemplary LSD 100 indicated by the box labeled 1D in FIG. 1C , according to one or more implementations. As discussed above, the body 130 of the sample cell 102 can at least partially define a channel or flow path 144 extending therethrough. For example, as shown in FIG. 1D , an inner surface 154 of the body 130 can at least partially define the flow path 144 extending therethrough. The flow path 144 can define a volume of the sample cell 102. The flow path 144 can be configured to include a central axis or centerline 156 extending therethrough and defining an overall orientation of the flow path 144. As shown in FIG. 1B , the flow path 144 and its central axis 156 can be aligned or coaxial with the light beam 146 emitted from the laser 108. The flow path 144 of the sample cell 102 can be interposed between the first lens 116 and the second lens 118. In at least one implementation, the first lens 116 and the second lens 118 can sealingly engage the body 130 of the sample cell 102 on opposite sides of the body 130, thereby preventing the flow of sample or effluent from the flow path 144 through an interface between the body 130 and the respective first lens 116 and second lens 118. In another implementation, a seal (e.g., a gasket, O-ring, etc.) (not shown) can be disposed between the body 130 and the first lens 116 and second lens 118 to provide a fluid-tight seal therebetween.

[0041] The flow path 144 can include an inner section 158 and two outer sections 160, 162 disposed along a centerline 156 of the flow path 144. As shown in FIG. 1D , the inner section 158 can be interposed between the two outer sections 160, 162. The inner section 158 can be fluidly coupled to the sample source 104 and configured to receive a sample or effluent from the sample source 104. For example, as shown in FIG. 1D with continued reference to FIG. 1A , the body 130 of the sample cell 102 can define an inlet 164 extending therethrough and configured to fluidly couple the sample source 104 to the inner section 158 via the line 106. In a preferred implementation, the inlet 164 is configured such that sample from the sample source 104 is directed toward the center or center of the flow path 144 or the inner section 158 of the flow path 144.

[0042] In at least one embodiment, the inner section 158 can be cylindrical or define a cylindrical volume and can have a circular cross-sectional profile. However, it should be appreciated that the cross-sectional profile can be any suitable shape and / or size. For example, the cross-sectional profile can be oval, rectangular, such as a rounded rectangle, or the like. The inner section 158 can have any suitable dimensions. In at least one embodiment, the inner section 158 can have a length extending between the two outer sections 160 and 162 of about 4 mm to about 12 mm or greater. For example, the inner section 158 can have a length from about 4 mm, about 5 mm, about 6 mm, about 7 mm, or about 7.5 mm to about 8.5 mm, about 9 mm, about 10 mm, about 11 mm, about 12 mm, or greater. In another example, inner section 158 can have a length of about 4 mm to about 12 mm, about 5 mm to about 11 mm, about 6 mm to about 10 mm, about 7 mm to about 9 mm, or about 7.5 mm to about 8.5 mm. In a preferred implementation, inner section 158 can have a length of about 7 mm to about 9 mm, preferably about 7.5 mm to about 8.5 mm, and more preferably about 8 mm. In at least one implementation, inner section 158 can have a diameter of about 1.2 mm to about 2.0 mm or greater. For example, inner section 158 can have a diameter of about 1.2 mm, about 1.3 mm, about 1.4 mm, about 1.5 mm, or about 1.55 mm to about 1.65 mm, about 1.7 mm, about 1.8 mm, about 1.9 mm, about 2.0 mm, or greater. In other examples, inner section 158 can have a diameter of about 1.2 mm to about 2.0 mm, about 1.3 mm to about 1.9 mm, about 1.4 mm to about 1.8 mm, about 1.5 mm to about 1.7 mm, or about 1.55 mm to about 1.65 mm. In a preferred implementation, inner section 158 can have a diameter of about 1.5 mm to about 1.7 mm, preferably about 1.55 mm to about 1.65 mm, and more preferably about 1.6 mm.

[0043] The outer sections 160, 162 of the flow channel 144 can be fluidly coupled to the inner section 158 and configured to receive a sample or effluent from the inner section 158. In at least one implementation, at least one of the first outer section 160 and the second outer section 162 can be cylindrical or define a cylindrical volume and can have a circular cross-sectional profile. For example, at least one of the first outer section 160 and the second outer section 162 can be sized and shaped similarly to the inner section 158 of FIG. 1D . In another implementation, at least one of the first outer section 160 and the second outer section 162 can be conical or frusto-conical such that the cross-sectional area of ​​the respective first end portions or inlets 166, 168 of the outer sections can be relatively smaller than the cross-sectional area of ​​the respective second end portions or outlets 170, 172 of the outer sections. In a preferred implementation, both the first outer section 160 and the second outer section 162 may be frusto-conical or define a truncated cone, with respective first end portions or inlets 166, 168 configured to receive the sample from the inner section 158 and respective second end portions or outlets 170, 172 configured to deliver the sample to a waste line 174 (see FIG. 1A).

[0044] The inner surface 154 of the body 130 can at least partially define the taper angles (θ1, θ2) of the first outer section 160 and the second outer section 162, respectively. For example, as shown in FIG. 1D , the portion of the inner surface 154 that defines or forms the first outer section 160 of the flow channel 144 and the centerline 156 of the flow channel 144 can define the taper angle (θ1) of the first outer section 160. In another example, the portion of the inner surface 154 that defines or forms the second outer section 162 of the flow channel 144 and the centerline 156 of the flow channel 144 can define the taper angle (θ2) of the second outer section 162. The first outer section 160 and the second outer section 162 can have any taper angle (θ1, θ2) that can enable or be configured to allow the LSD 100 and its detectors 110, 112, 114 to receive scattered light at any desired angle. 1D depicts the taper angles (θ1, θ2) of the first outer section 160 and the second outer section 162 as being relatively equal to one another, it should be appreciated that one of the taper angles (θ1, θ2) can be relatively greater than the other. It should further be appreciated that any one or more attributes (e.g., length, taper angle, diameter, shape, size, etc.) of the first outer section 160 and the second outer section 162 can be different. In a preferred implementation, the attributes (e.g., length, taper angle, diameter, shape, size, etc.) of the first outer section 160 and the second outer section 162 are the same or substantially the same.

[0045] Each of the outer sections 160, 162 can be fluidly coupled to a waste line 174. For example, as shown in FIGS. 1A and 1D , the body 130 can define a first outlet 176 and a second outlet 178 that extend through the body 130 and are configured to fluidly couple the first outer section 160 and the second outer section 162 to the waste line 174 via a first outlet line 180 and a second outlet line 182, respectively. As further shown in FIG. 1D , the first outlet 176 and the second outlet 178 can be fluidly coupled to the waste line 174 via a first outlet line 180 and a second outlet line 182, respectively. The outlets 178 may be fluidly coupled to the second end portions 170, 172 of the outer sections 160, 162, respectively. It should be appreciated that the orientation (e.g., circumferential orientation) or location of the inlet 164 and the first and second outlets 176, 178 may vary. For example, the inlet 164 may be circumferentially aligned with at least one of the first and second outlets 176, 178. In another example, the inlet 164 may be circumferentially offset from at least one of the first and second outlets 176, 178. In yet another example, the first and second outlets 176, 178 may be circumferentially aligned with one another or circumferentially offset from one another.

[0046] As shown in FIG. 1D , the body 130 of the sample cell 102 can define an aperture 184 that extends through at least a portion of the body 130 and is configured to allow light (e.g., scattered light) from the inner section 158 to be directed or transmitted to the third detector 114. The aperture 184 can be sealed with an optically transparent material 186, such as a quartz crystal, thereby allowing the light from the inner section 158 to be directed to the third detector 114. In the exemplary implementation shown in FIGS. 1B and 1D , the optically transparent material 186 can be shaped to refract a portion of the light toward the third detector 114. For example, the optically transparent material 186 can be a sixth lens (e.g., a ball lens) that seals the aperture 184 and is configured to at least partially refract the light toward the third detector 114.

[0047] The body 130 can include or be made of any suitable material. The body 130 can be configured so that the inner surface 154 of the body 130 attenuates light reflection. For example, the body 130 can be made of a non-reflective material. In another example, the body 130 can be at least partially made of a reflective material and at least partially coated with a non-reflective material. In at least one implementation, the sample cell 102 can be made of quartz, such as black quartz. In an exemplary implementation, the body 130 can include or be made of a polymer. Exemplary polymers can be or include, but are not limited to, polyolefin-based polymers, acrylic-based polymers, polyurethane-based polymers, ether-based polymers, polyester-based polymers, polyamide-based polymers, formaldehyde-based polymers, silicone-based polymers, any copolymers thereof, or any combination thereof.For example, the polymer may be poly(ether ether ketone) (PEEK), TORLON®, polyamideimide, polyethylene (PE), polyvinyl fluoride (PVF), polyvinyl chloride (PVC), polyvinylidene fluoride (PVDF), polyvinylidene chloride (PVDC), polychlorotrifluoroethylene (PCTFE), polytetrafluoroethylene (PTFE), polypropylene (PP), poly(1-butene), poly(4-methylpentene), polystyrene, polyvinylpyridine, polybutadiene, polyisoprene, polychloroprene, styrene-acrylonitrile copolymer, acrylonitrile-butadiene-styrene terpolymer, ethylene-methacrylic acid copolymer, styrene-acrylonitrile ... The polymer may include, but is not limited to, ethylene-butadiene rubber, tetrafluoroethylene copolymer, polyacrylate, polymethacrylic acid, polyacrylamide, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl ether, polyvinylpyrrolidone, polyvinylcarbazole, polyurethane, polyacetal, polyethylene glycol, polypropylene glycol, epoxy resin, polyphenylene oxide, polyethylene terephthalate, polybutylene terephthalate, polydihydroxymethylcyclohexyl terephthalate, cellulose ester, polycarbonate, polyamide, polyimide, any copolymer thereof, or any combination thereof. The polymer may be or include, but is not limited to, an elastomer or elastomeric material, synthetic rubber, etc. Exemplary elastomeric materials and synthetic rubbers include VITON (registered trademark). The rubber may include, but is not limited to, polyethylene terephthalate (PET), nitrile, polybutadiene, acrylonitrile, polyisoprene, neoprene, butyl rubber, chloroprene, polysiloxane, styrene-butadiene rubber, hydrin rubber, silicone rubber, ethylene-propylene-diene terpolymer, any copolymer thereof, or any combination thereof.

[0048] 1A-1D , in an exemplary operation of the LSD 100, a sample source 104 (e.g., a liquid chromatograph with a gel permeation chromatography column) can inject or direct a sample or effluent (e.g., a dilute polymer solution) into and through the flow path 144 of the sample cell 102 via line 106 and inlet 164. As shown in FIG. 1D , the sample from the sample source 104 can be directed toward the center or center of the flow path 144 or inner section 158 of the sample cell 102. As the sample flows into the center of the inner section 158, the sample flow can be split so that a first portion of the sample flows toward a first outer section 160 and a second portion of the sample flows toward a second outer section 162. The portions of the sample within the first outer section 160 and the second outer section 162 can then exit the sample cell 102 via the first outlet 176 and the second outlet 178 and the first outlet line 180 and the second outlet line 182, respectively, and be directed to the waste line 174.

[0049] The flow rates of the sample through the first outer section 160 and the second outer section 162 can be modified or adjusted (i.e., increased or decreased) by adjusting the lengths of the first outlet line 180 and the second outlet line 182, respectively. In at least one implementation, the flow rates of the first and second portions of the sample through the first outer section 160 and the second outer section 162 can be the same or substantially the same. For example, the flow rate of the first portion of the sample through the first outer section 160 is the same or substantially the same as the flow rate of the second portion of the sample through the second outer section 162. In another implementation, the flow rates of the first and second portions of the sample through the first outer section 160 and the second outer section 162 can be different. However, it should be appreciated that when the flow rates through the first outer section 160 and the second outer section 162 are different, a time correction can be applied.

[0050] As sample flows through the flow path 144 of the sample cell 102, the laser 108 can emit a light beam 146 along and through a centerline 156 of the flow path 144 via a bore 152 of the second mirror 128. In at least one implementation shown in FIG. 1A , the light beam 146 can be transmitted through a third lens 120, which can at least partially focus the light beam 146 along the centerline 156 of the flow path 144. In another implementation, the third lens 120 can be omitted. In at least one implementation, an optional screen or diaphragm 188 is disposed between the laser 108 and the sample cell 102 to filter stray light (e.g., a halo of light) from the light beam 146, providing a "clean-up" effect. It may be configured to "cleanup", isolate, or otherwise filter For example, the diaphragm 188 can define a hole or aperture (e.g., an adjustable aperture / iris) that is capable of or configured to filter out stray light from the light beam 146.

[0051] At least a portion of the light beam 146 may travel or be transmitted from the laser 108 to and through the sample cell 102, the first lens 116, the bore 152 of the second mirror 128, and / or the optional diaphragm 196. For example, at least a portion of the light beam 146 may travel from the laser 108 to the sample cell 102, the first lens 116, the second mirror 128, and / or the optional diaphragm 196 without being obstructed or interacting with any of the analytes in the sample. The remaining portion of the light beam 146 transmitted through the flow path 144 may interact with or otherwise contact analytes suspended, dispersed, or otherwise disposed within the sample and / or flowing through the sample cell 102.

[0052] Contact between the light beam 146 and the analytes in the sample can generate or induce scattered light or analyte scattered beams 190, 192, 194 (see FIGS. 1A and 1B). For example, contact between the light beam 146 and the analytes contained in the sample or flowing through the flow path 144 of the sample cell 102 can generate a forward analyte scattered beam 190 and a backward analyte scattered beam 192. In another example, contact between the light beam 146 and the analytes contained in the sample or flowing through the flow path 144 of the sample cell 102 can generate a right-angle scattered beam 194 in a direction approximately perpendicular to the light beam 146.

[0053] It should be appreciated that flowing the sample into the center of the channel 144 via the inlet 164 allows the sample to interact with the light beam 146 immediately, thereby minimizing peak broadening. For example, flowing the sample directly into the center of the channel 144 allows the sample to interact with the light beam 146 without flowing through at least half of the length or volume (e.g., laterally or axially) of the sample cell 102 and the channel 144 of the sample cell 102. Flowing the sample directly into the center of the channel 144 also minimizes the amount of time required for the sample to interact with the light beam 146 and generate the analyte scattered beams 190, 192, 194. It should further be appreciated that one or more components of the LSD 100 are configured such that only light scattered from the center of the channel 144 is collected by the detectors 110, 112, 114. For example, at least one of the first lens 116, the first mirror, and the fourth lens 122 can be configured to separate forward light scatter 190 arising from the center of the flow channel 144 from forward light scatter 190 arising from other regions of the flow channel 144, such that the first detector 110 receives only the forward light scatter 190 arising from the center of the flow channel 144. Similarly, at least one of the second lens 116, the second mirror 128, and the fifth lens 124 can be configured to separate backlight scatter 192 arising from the center of the flow channel 144 from backlight scatter 192 arising from other regions of the flow channel 144, such that the second detector 112 receives only the backlight scatter 192 arising from the center of the flow channel 144.

[0054] As shown in FIG. 1A , the forward analyte scattered beam or forward scattered light 190 can be directed toward the first detector 110 via the first lens 116, the first mirror 126, and the fourth lens 122. At least a portion of the forward scattered light 190 can be at least partially refracted by a convex surface defined along the first end portion 136 of the first lens 116. As shown in FIG. 1A , the forward scattered light 190 can be refracted by the convex surface toward the first mirror 126, which can refract the forward scattered light 190 toward the first detector 110 via the fourth lens 122. The fourth lens 122 can collect the forward scattered light 190 and direct and / or focus the forward scattered light 190 toward the first detector 110.

[0055] The forward scattered light 190 can be scattered at a variety of angles from greater than 0 degrees to less than 90 degrees relative to the light beam 146 emitted from the laser 108. For example, the forward scattered light 190 can be scattered at any angle from greater than 0 degrees, about 5 degrees, about 10 degrees, about 15 degrees, about 20 degrees, about 25 degrees, about 30 degrees, about 35 degrees, about 40 degrees, or about 45 degrees, to about 50 degrees, about 55 degrees, about 60 degrees, about 65 degrees, about 70 degrees, about 75 degrees, about 80 degrees, about 85 degrees, or less than about 90 degrees. In another example, the forward scattered light 190 can be scattered at an angle from about 5 degrees, about 6 degrees, about 7 degrees, about 8 degrees, about 9 degrees, or about 9.5 degrees, to about 10.5 degrees, about 11 degrees, about 12 degrees, about 13 degrees, about 14 degrees, or about 15 degrees relative to the light beam 146 emitted from the laser 108. The forward scattered light 190 may be scattered at any angle up to 5 degrees. In yet another example, the forward scattered light 190 may be scattered at an angle between about 5 degrees and about 15 degrees, between about 6 degrees and about 14 degrees, between about 7 degrees and about 13 degrees, between about 8 degrees and about 12 degrees, between about 9 degrees and about 11 degrees, or between about 9.5 degrees and about 10.5 degrees. It should be appreciated that the LSD 100 and any of its components may be configured to receive forward scattered light 190 scattered at any angle greater than 0 degrees and less than 90 degrees. For example, any attribute (e.g., shape, location, orientation, etc.) of one or more of the first detector 110, the first lens 116, the first mirror 126, the fourth lens 122, and / or any additional optional diaphragms may be adjusted, modified, or otherwise configured to enable the first detector 110 to receive any of the forward scattered light 190. In a preferred implementation, the LSD 100 and its first detector 110 are configured to receive or collect the forward scattered light 190 at an angle of about 9 degrees to about 11 degrees relative to the light beam 146, preferably at an angle of about 9.5 degrees to about 10.5 degrees, and more preferably at an angle of about 10 degrees.

[0056] 1A, the backscattered analyte beam or backscattered light 192 can be directed towards the second detector 112 via the second lens 118, the second mirror 128, and the fifth lens 124. At least a portion of the backscattered light 192 can be at least partially refracted by the convex surface of the second lens 118. As shown in FIG. 1A, the backscattered light 192 can be refracted by the convex surface towards the second mirror 128, which can refract the backscattered light 192 towards the second detector 112 via the fifth lens 124. The fifth lens 124 can collect the backscattered light 192 and direct and / or focus the backscattered light 192 towards the second detector 112.

[0057] The backscattered light 192 can be scattered at a variety of angles from greater than 90 degrees to less than 180 degrees relative to the light beam 146 emitted from the laser 108. For example, the backscattered light 192 can be scattered at any angle from greater than 90 degrees, about 95 degrees, about 100 degrees, about 105 degrees, about 110 degrees, about 115 degrees, about 120 degrees, about 125 degrees, about 130 degrees, or about 135 degrees, to about 140 degrees, about 145 degrees, about 150 degrees, about 155 degrees, about 160 degrees, about 165 degrees, about 170 degrees, about 175 degrees, or less than about 180 degrees. In another example, the backscattered light 192 can be scattered at any angle from about 165 degrees, about 166 degrees, about 167 degrees, about 168 degrees, about 169 degrees, or about 169.5 degrees to about 170.5 degrees, about 171 degrees, about 172 degrees, about 173 degrees, about 174 degrees, or about 175 degrees relative to the light beam 146 emitted from the laser 108. In yet another example, the backscattered light 192 can be scattered at an angle between about 165 degrees and about 175 degrees, between about 166 degrees and about 174 degrees, between about 167 degrees and about 173 degrees, between about 168 degrees and about 172 degrees, between about 169 degrees and about 171 degrees, or between about 169.5 degrees and about 170.5 degrees. It should be appreciated that the LSD 100 and any of its components can be configured to receive backscattered light 192 scattered at any angle greater than 90 degrees and less than 180 degrees. For example, any attribute (e.g., shape, location, orientation, etc.) of one or more of the second detector 112, the second lens 118, the second mirror 128, the fifth lens 124, and / or any further optional diaphragms can be adjusted, modified, or otherwise configured to enable the second detector 112 to receive any backscattered light 192. In a preferred implementation, the LSD 100 and its second detector 112 are configured to receive or collect the backscattered light 192 at an angle between about 169 degrees and about 171 degrees relative to the light beam 146, preferably at an angle between about 169.5 degrees and about 170.5 degrees, and more preferably at an angle of about 170 degrees.

[0058] 1D, the right-angle analyte scattered beam or right-angle scattered light 194 can be directed toward the third detector 114 through an aperture 184 extending between the third detector 114 and the inner section 158 of the flow channel 144. In at least one implementation, 1D , the third detector 114 can be disposed within the aperture 184 adjacent to the inner section 158. In another implementation shown in FIG. 1D , an optically transparent material 186 can be disposed within the aperture 184 to seal the inner section 158 of the flow channel 144. The optically transparent material 186 can be any suitable material that allows the right-angle scattered light 194 to be transmitted to the third detector 114. The optically transparent material 186 can be shaped to refract at least a portion of the right-angle scattered light 194 towards the third detector 114. For example, as discussed above, the optically transparent material 186 can be a ball lens shaped to refract the right-angle scattered light 194 towards the third detector 114.

[0059] The right-angle scattered light 194 can be scattered in a direction generally perpendicular to the light beam 146. For example, the right-angle scattered light 194 can be scattered at an angle from about 87 degrees, about 88 degrees, about 89 degrees, about 89.5 degrees, or about 90 degrees to about 90.5 degrees, about 91 degrees, about 92 degrees, or about 93 degrees. In other examples, the right-angle scattered light 194 can be scattered at an angle between about 87 degrees and about 93 degrees, between about 88 degrees and about 92 degrees, between about 89 degrees and about 91 degrees, or between about 89.5 degrees and about 90.5 degrees. It should be appreciated that the LSD 100 and any component thereof can be configured to receive right-angle scattered light 194 that is scattered in a direction generally perpendicular to the light beam 146. For example, the shape, location, orientation, or any other attributes of the optically transparent material 186 (e.g., the sixth lens) and / or the third detector 114 can be adjusted, modified, or otherwise configured so that the third detector 114 receives any right-angle scattered light of the right-angle scattered light 194. In a preferred implementation, the LSD 100 and its third detector 114 are configured to receive or collect the right-angle scattered light 194 at an angle between about 89 degrees and about 91 degrees relative to the light beam 146, preferably at an angle between about 89.5 degrees and about 90.5 degrees, and more preferably at an angle of about 90 degrees.

Claims

1. a body defining a flow passage extending axially therethrough, the flow passage comprising a cylindrical inner section interposed between a first outer section and a second outer section; the first outer section is frusto-conical, a first end portion of the first outer section being in direct fluid communication with the inner section and having a cross-sectional area relatively smaller than a cross-sectional area at a second end portion of the first outer section; the second outer section is frusto-conical, a first end portion of the second outer section being in direct fluid communication with the inner section and having a cross-sectional area relatively smaller than a cross-sectional area at a second end portion of the second outer section; the body further defines an inlet in direct fluid communication with the inner section and configured to direct a sample into the inner section of the flow channel; the body further defines a first outlet and a second outlet extending therethrough, the first outlet and the second outlet configured to fluidly couple the respective second end portions of the first outer section and the second outer section to a waste line; the body defining an aperture extending radially therethrough, the aperture being in direct fluid communication with the inner section of the flow passage; and further comprising an optically transparent material disposed within the aperture. Light scattering detector sample cell.

2. 2. The sample cell of claim 1, wherein the body defines a first recess extending axially therethrough, the first recess being in fluid communication with the first outer section and configured to accommodate a first lens of the light scattering detector.

3. 3. The sample cell of claim 1, wherein the body defines a second recess extending axially therethrough, the second recess being in fluid communication with the second outer section and configured to accommodate a second lens of the light scattering detector.

4. a laser configured to emit a beam of light; a sample cell comprising a body defining a flow path extending axially therethrough, the flow path having a centerline aligned with the light beam, the flow path comprising a cylindrical inner section interposed between a first outer section and a second outer section; the first outer section is frusto-conical, a first end portion of the first outer section being in direct fluid communication with the inner section and having a cross-sectional area relatively smaller than a cross-sectional area at a second end portion of the first outer section; the second outer section is frusto-conical, a first end portion of the second outer section being in direct fluid communication with the inner section and having a cross-sectional area relatively smaller than a cross-sectional area at a second end portion of the second outer section; the body further defines an inlet in direct fluid communication with the inner section and configured to direct a sample into the inner section of the flow channel; the body further defines a first outlet and a second outlet extending therethrough, the first outlet and the second outlet configured to fluidly couple the respective second end portions of the first outer section and the second outer section to a waste line; the body defining an aperture extending radially therethrough, the aperture being in direct fluid communication with the inner section of the flow path; A sample cell; at least one detector operably coupled to the sample cell and configured to receive scattered light emitted from the sample cell; and the at least one detector includes a third detector disposed within the aperture and configured to receive right-angle scattered light from the sample cell. Light scattering detector.

5. 5. The light scattering detector of claim 4, further comprising a first lens and a second lens, the first lens disposed adjacent to the first outer section of the flow path and the second lens disposed adjacent to the second outer section of the flow path.

6. the light scattering detector further comprises a first mirror; the at least one detector includes a first detector; and the first mirror is disposed proximate to the first lens and configured to reflect forward scattered light from the sample cell to the first detector.

6. The light scattering detector of claim 5.

7. the light scattering detector further comprises a second mirror; the at least one detector includes a second detector; and the second mirror is disposed proximate to the second lens and configured to reflect backscattered light from the sample cell to the second detector.

7. The light scattering detector of claim 6.

8. 5. A method of using the light scattering detector of claim 4, comprising: emitting the light beam from the laser into and through the flow path of the sample cell; flowing a sample into the inner section of the flow path through the inlet of the sample cell; flowing a first portion of the sample from the inner section into and through the first frusto-conical outer section from the first end portion to the second end portion of the first frusto-conical outer section; flowing a first portion of the sample from the second end portion of the first frusto-conical outer section through the first outlet to the waste line; A method comprising:

9. flowing a second portion of the sample from the inner section into and through the second frusto-conical outer section from the first end portion to the second end portion of the second frusto-conical outer section; flowing the second portion of the sample from the second end portion of the second frusto-conical outer section through the second outlet to the waste line; The method of claim 8 further comprising:

10. the light scattering detector further comprises a first mirror; the at least one detector includes a first detector; the first mirror is disposed proximate to the first lens and configured to reflect forward scattered light from the sample cell to the first detector; and and directing the forward scattered light emitted from the flow path to the first detector by the first mirror.

10. The method according to claim 8 or 9.

11. the light scattering detector further comprises a second mirror; the at least one detector includes a second detector; and the second mirror is disposed proximate to the second lens and configured to reflect backscattered light from the sample cell to the second detector; and and directing the backscattered light emitted from the flow path to the second detector by the second mirror. The method according to any one of claims 8 to 10.

12. The method of any one of claims 8 to 11, further comprising directing the orthogonally scattered light emitted from the flow path to the third detector.

13. The sample cell of claim 1 , wherein the body is made of a non-reflective material or is provided with a coating of a non-reflective material.

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