Devices Comprising Transparent Polymers Having Hydrophilic Coatings and Methods for Making the Same

Abstract

To provide a device including a transparent polymer with a hydrophilic coating, formed by cost-effective means.SOLUTION: A device includes a hydrophilic layer on a portion of an inner surface of a transparent polymer forming a body, wherein the hydrophilic layer includes a sulfonated inner surface of the transparent polymer, silica, silicon oxycarbide, an O2 plasma treatment of the transparent polymer, or a combination thereof. The device can be a nebulizer or a spray chamber, for example used in an inductively coupled plasma device. A method of making the device is also disclosed.SELECTED DRAWING: None

Description

[Technical Field]

[0001] [Related Applications] This application claims priority to U.S. Provisional Application No. 63 / 350,800, filed June 9, 2022, the entire disclosure of which is incorporated herein by reference.

[0002] The present disclosure generally relates to a device comprising a hydrophilic layer on a portion of an inner surface of a transparent polymer forming a body, the hydrophilic layer comprising a sulfonated inner surface of the transparent polymer, silica, silicon oxycarbide, O2 plasma treatment of the transparent polymer, or a combination thereof. The device may be, for example, a nebulizer or atomization chamber for use in an inductively coupled plasma device. A method for manufacturing the device is also disclosed. [Background technology]

[0003] In an inductively coupled plasma optical emission spectroscopy (ICP-OES) or inductively coupled plasma mass spectroscopy (ICP-MS) sample introduction system, the sample enters a nebulizer and is atomized into a fine aerosol by the pneumatic action of an airflow that disperses the liquid sample into tiny droplets. This atomized spray flows into a nebulization chamber, where large and small droplets are separated along with an inert gas. For ICP, monodisperse droplets smaller than 10 μm are ideal, but large droplets affect signal stability and intensity. For this reason, only the smallest droplets are allowed to pass through the nebulization chamber and into the plasma for efficient atomization and eventual ionization of the sample's elemental components, thereby achieving accurate quantitative analysis. Specifically, the droplets are sorted by the design of the nebulization chamber and the vortex of the airflow, causing larger droplets to impact the nebulization chamber wall due to centrifugal force, while the smaller droplets continue through the plasma, where they are ionized at high temperatures and analyzed for elemental composition. The larger droplets that impact the atomization chamber surface drip down the atomization chamber wall and out of the flow path so as not to interfere with the finer atomized droplets.

[0004] To achieve drainage, which requires the removal of relatively large droplets from the spray chamber surface, the surface itself must be capable of excluding solvents. Solvents such as water and alcohol are easily drained away when the spray chamber surface is hydrophilic in nature. Glass, which is hydrophilic in nature, is typically used for spray chambers, allowing for the necessary drainage. Glass is also resistant to the acids used in ICPs and is transparent, allowing users to observe the drainage of solutions that hit the spray chamber walls. Drainage using hydrophilic surfaces such as glass is fast because less time is required for sample "washout" before the next analysis. If the surface becomes contaminated or loses its hydrophilicity, these washouts may not be sufficient to remove sample residue, leading to erroneous analyses or prolonged washout times. Over time, glass spray chambers need to be cleaned or replaced, which is costly for users. Additionally, production of glass spray chambers requires skilled glass technicians to manually mold the glass, which is expensive (hundreds of dollars per piece) and somewhat restricts design options.

[0005] Other existing materials for spray chambers, primarily for special applications (e.g., hydrofluoric acid resistance), include perfluoropolymers (e.g., perfluoroalkoxyalkanes (PFA) or polytetrafluoroethylene (PTFE)) and fluorocarbon-containing plastics, such as the inert plastic PEEK. Perfluoropolymers are generally opaque, which inhibits visual observation of the solution spray and introduction (considered important by ICP-OES users). Furthermore, because perfluoropolymers are hydrophobic, expensive hydrophilic coatings must be applied to the interior surfaces to prevent liquid beading in the spray chamber, which can affect analysis and waste discharge.

[0006] A cost-friendly solution for manufacturing high performance atomization chambers is desired.

[0007] Glass spray chamber shapes are limited to a combination of preformed (molded or extruded) components and minor manual modifications performed by glass blowing. There is a need for a device that can be inexpensively made into a variety of shapes to accommodate many purposes without being labor- or cost-intensive.

[0008] Glass spray chambers shatter when dropped from a benchtop to the floor. Additionally, glass spray chambers can break under use and clean conditions. There is a need for a device that has adequate impact resistance under ambient use conditions. Furthermore, the device should be resistant to cracking. Summary of the Invention

[0009] In one aspect, the present disclosure discloses a device comprising a hydrophilic layer on a portion of an inner surface of a transparent polymer forming a body, wherein the hydrophilic layer comprises a sulfonated inner surface of the transparent polymer, silica, silicon oxycarbide, O2 plasma treatment of the transparent polymer, or a combination thereof.

[0010] In another aspect, the present disclosure discloses a method of manufacturing a device, the method comprising: forming a device by molding or injection molding a transparent polymer; and chemically modifying a portion of an interior surface of the device to render said portion hydrophilic.

[0011] Additional features and advantages of various embodiments will be set forth in part in the description that follows, and in part will be obvious from the description, or may be learned by practice of various embodiments. The objectives and other advantages of various embodiments will be realized and attained by means of the elements and combinations particularly pointed out in the description of the present disclosure.

[0012] Features of the present disclosure are illustrated by way of example, but not limitation, in the following figures, in which like numerals refer to like elements and in which: [Brief explanation of the drawings]

[0013] [Figure 1A-C] 1A-1C illustrate various devices according to aspects of the present invention. [Figure 2] 1 is a graph showing the surface hydrophilicity of sulfonated polystyrene compared to devices without a hydrophilic coating. [Figure 3] Figure 3A is a photograph showing an untreated polystyrene coupon in a simulated spray chamber showing aerosol beading, and Figure 3B is a photograph showing a sulfonated polystyrene coupon showing no aerosol beading. [Figure 4] 1 is a graph showing the surface hydrophilicity of sulfonated polystyrene compared to a device without a hydrophilic coating and after cleaning with a solvent. [Figure 5A-C] Figure 5A is a photograph showing the non-beading of the sprayed solution from a plasma-enhanced chemical vapor deposition (PECVD) silica-coated polystyrene coupon contacted with 20% aqua regia in a simulated spray chamber. Figure 5B is a photograph showing the non-beading of the sprayed solution from a PECVD silica-coated polystyrene coupon contacted with A-solv in a simulated spray chamber and then treated with ultrasound. Figure 5C is a photograph showing the beading of the aerosol from an untreated polystyrene coupon in a simulated spray chamber. [Figure 6] 1 is a graph showing the surface hydrophilicity (as measured by static water contact angle) of glycol-modified polyethylene terephthalate coated with silica after cleaning with a solvent followed by ultrasonic cleaning in a cleaning solution over a period of time. [Figure 7]Figure 7A is an optical microscope image of a polyethylene terephthalate glycol (PETG) coupon coated with PECVD silica after 25 days of contact with 20% aqua regia and then ultrasonicated for 5 days in 5% Triton X-100. Figure 7B is an optical microscope image of a PETG coupon coated with PECVD silica after 25 days of contact with A-solv and then ultrasonicated for 5 days in 5% Triton X-100. [Figure 8] 1 is a graph showing the surface hydrophilicity of O 2 plasma treated (freshly treated) cyclic olefin polymers compared to devices without a hydrophilic coating and devices after cleaning with solvent. [Figure 9A-B] Figure 9A shows images of an untreated cyclic olefin coupon in a simulated atomization chamber showing aerosol beading, and Figure 9B shows images of an O2 plasma-treated coupon in a simulated atomization chamber showing aerosol non-beading. [Figure 10] 1 is a graph showing the surface hydrophilicity of O2 plasma treated (freshly treated) polyethylene terephthalate with glycol modification compared to devices without a hydrophilic coating and devices after cleaning with solvent. [Figure 11A-B] Figure 11A shows images of an untreated polyethylene terephthalate coupon with glycol modification in a simulated atomization chamber, demonstrating aerosol beading, and Figure 11B shows images of an O2 plasma-treated coupon in a simulated atomization chamber, demonstrating aerosol non-beading. [Figure 12A-C] 1 is an image showing the measurement of water contact angle of a silica film on a silicon wafer. [Figure 13A-C] 1 is an image showing water contact angle measurements of silica films on silicon wafers with prolonged ozone exposure. [Figure 14]1 shows the sensitivity results of a silica-coated PET spray chamber (LE12) labeled (1) before cleaning and (2) after cleaning in a 5% Citranox (LE12-1 and LE12-2) solution or a 5% Extran MA02 (LE12-3) solution. LE12-4 was not cleaned between experiments. [Figure 15] 1 shows the accuracy results of a silica-coated PET spray chamber (LE12) labeled (1) before cleaning and (2) after cleaning in a 5% Citranox (LE12-1 and LE12-2) solution or a 5% Extran MA02 (LE12-3) solution. LE12-4 was not cleaned between experiments. [Figure 16] 1 shows the results of washout of silica-coated PET nebulization chambers (LE12) labeled (1) before cleaning and (2) after cleaning in 5% Citranox (LE12-1 and LE12-2) or 5% Extran MA02 (LE12-3) solutions. LE12-4 was not cleaned between experiments. [Figure 17A-D] Optical microscopy analyses of SiO2-coated PET coupons after exposure to 20% aqua regia and 5% Extran MA02 solutions: (FIG. 17A) Sample LE16-C11, which was subjected to a 30-minute ozone treatment and four cleaning cycles over 17 days prior to ALD SiO2 deposition; (FIG. 17B) Sample LE16-C11, which was subjected to nine cleaning cycles over 47 days; (FIG. 17C) Sample LE10-C1, which was subjected to three cleaning cycles over 17 days without ozone treatment prior to ALD coating; and (FIG. 17D) Sample #11-C1, coated with PECVD SiO2 from Thierry Corporation, exposed to 20% aqua regia for only 5 days without cleaning. [Figures 18A-E] 1 is an image showing a silica coated PET spray chamber setup with water beading on the interior surface of the spray chamber. DETAILED DESCRIPTION OF THE INVENTION

[0014] For the sake of brevity and specificity, the present disclosure has been described primarily by reference to examples thereof. Numerous specific details are set forth in the following description to provide a thorough understanding of the present disclosure. However, it will be readily understood that the present disclosure can be practiced without limitation to these specific details. In other instances, some methods and structures have not been described in detail so as not to unnecessarily obscure the present disclosure.

[0015] Additionally, the elements depicted in the accompanying drawings may include additional components, and some components depicted in the drawings may be omitted and / or modified without departing from the scope of the present disclosure. Furthermore, the elements depicted in the drawings may not be to scale, so the elements may have different sizes and / or configurations than those shown in the drawings.

[0016] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are intended to provide an explanation of various embodiments of the teachings of the present disclosure. In its broad and varied embodiments, the present disclosure discloses a device comprising a hydrophilic layer on a portion of an inner surface of a transparent polymer forming a body thereof, said hydrophilic layer comprising a sulfonated (or chemically modified) inner surface of the transparent polymer, silica, silicon oxycarbide, O2 plasma treatment of the transparent polymer, or a combination thereof.

[0017] The devices disclosed herein can be shaped and prepared in a cost-effective manner. In this manner, the devices may be disposable and / or reusable. The devices may be transparent or nearly transparent to allow observation of the device contents and the solution atomization process. Additionally, the devices may be resistant to solvents used in inductively coupled plasma processes to extend the life of the devices. The solutions used in inductively coupled plasma processes may inhibit beading on the interior surface of the device. In particular, a hydrophilic layer on a portion of the interior surface of the device may inhibit beading by flattening, coalescing, and / or allowing fluid droplets to drain. In particular, the hydrophilic layer may render the atomization chamber hydrophilic, resistant to low pH environments, and / or capable of being fabricated from clear plastic in a more cost-effective manner.

[0018] The device may be a nebulizer (as shown in FIG. 1A), a nebulization chamber (as shown in FIGS. 1B and 1C), or an attached sample introduction container. In one embodiment, the device may be a nebulization chamber having a reduced width and height in the upper chamber. The reduction in the upper chamber may be equivalent to a reduced volume in the upper chamber, reducing the likelihood that aerosol droplets will be trapped in the upper chamber. The device may also be a nebulization chamber having a relatively larger volume in the lower chamber (approximately 166% of its original size), allowing larger aerosol droplets to circulate away from the internal collection tube. The nebulization chamber may be a one-piece structure or may include separate connectable members, such as a first member and a second member.

[0019] Nebulizers may have concentric and parallel passes. Nebulization chambers may include cyclone (single and double pass) and Scott types.

[0020] The device may be a body having one or more inlets and one or more outlets. The body may have an outer surface and an inner surface. The body may be formed of a transparent material. In one embodiment, the transparent material may be any transparent material whose surface is or can be modified or coated to produce a hydrophilic layer. The transparent material may be a transparent polymer. Non-limiting examples of transparent polymers for use in the device include polystyrene, glycol-modified polyethylene terephthalate, polyethylene terephthalate, cyclic olefin polymers, and polycarbonates. Examples of commercially available cyclic olefin polymers include ZEONOR® 1020 and ZEONOR® 790 manufactured by Zeon Corporation. The transparent polymer may be polystyrene.

[0021] The body of the device may be formed by additive manufacturing, such as three-dimensional printing, or injection molding. These fabrication methods allow for a wide variety of modifications to the body, such as the atomizing chamber, design, shape, and / or size.

[0022] The device, including its interior surface, may be formed of a transparent polymer. A portion of the interior surface of the device may be modified, surface treated, or coated to create a hydrophilic layer. "A portion" means at least 1%, for example, about 5% to about 100%, for example, about 50% to about 99%, and as a further example, about 75% to about 95%, of the interior surface of the device, and is understood to include subranges and endpoints therebetween.

[0023] The hydrophilic layer may be any coating, surface treatment, and / or surface modification that can impart hydrophilicity or substantial hydrophilicity to a portion of the interior surface of the transparent polymer. For example, the hydrophilic layer can inhibit the formation of liquid beads on a portion of the interior surface of the transparent polymer. Non-limiting examples of hydrophilic layers include sulfonated (carboxylated, aminated, hydroxylated, or other chemical moieties that can impart hydrophilic properties) interior surfaces of transparent polymers, silica, silicon oxycarbide, O2 plasma treatment of transparent polymers, or combinations thereof.

[0024] In one embodiment, the transparent polymer may be polystyrene, which may be chemically modified as shown below to create a hydrophilic layer, i.e., a sulfonated inner surface of the transparent polymer.

[0025] [ka]

[0026] In another embodiment, the device may be formed of a transparent polymer such as polyethylene terephthalate or polyethylene terephthalate with glycol modification. A hydrophilic layer of silica or silicon oxycarbide may be deposited on a portion of the interior surface of the transparent polymer using a conventional deposition process such as plasma-enhanced chemical vapor deposition (PECVD). For example, a gas feed of oxygen:hexamethyldisiloxane (HDMSO) 3:1, or even 12:1, may be applied to a portion of the interior surface.

[0027] In another embodiment, the device may be formed from a transparent polymer, such as a cyclic olefin polymer. A portion of the inner surface of the transparent polymer may be surface-modified using an O2 plasma treatment to create a hydrophilic layer on the inner surface. The O2 plasma treatment may be performed at 400 mTorr oxygen for 5 minutes at 500 W.

[0028] The device may be a spray chamber containing polyethylene glycol. A portion of the inner surface of the spray chamber may have a hydrophilic layer of silica. The hydrophilic layer of silica may be formed using atomic layer deposition. A first precursor, such as a silicon source, may be used to react with the inner surface of the device body to form a monolayer. A second precursor, such as an oxygen source, may be metered in such a way that it reacts with the monolayer to form a single fully reacted monolayer, which is a complete cycle. The cycle may be repeated several times to control the thickness of the hydrophilic layer formed from multiple fully reacted monolayers.

[0029] The present disclosure provides a method of manufacturing a device, the method comprising: forming a device by molding or injection molding a transparent polymer; and chemically modifying a portion of the interior surface of the device to render said portion hydrophilic. The step of forming the device may further comprise separately molding two halves of the device and joining the two halves to form a transparent polymer device. The chemical modification step may further comprise immersing a device formed from the transparent polymer in a sulfuric acid bath.

[0030] In an alternative embodiment, a method of manufacturing a device may include forming a device by molding or injection molding a transparent polymer and chemically modifying a portion of a surface of the device to render said portion hydrophilic. Forming the device may further include separately molding two halves of the device. The chemically modifying step may further include immersing a device formed from the transparent polymer in a sulfuric acid bath. The method may include joining the two halves to form the device after the chemically modifying step.

[0031] With respect to the aforementioned chemically modifying method step, the chemically modifying step may include applying sulfuric acid at a temperature ranging from about -5°C to less than about 80°C for a time ranging from about 1 minute to about 1 hour. The concentration of the sulfuric acid may be at least 96%. The sulfuric acid may be oleum containing about 0.01% to about 20% free SO3. In this manner, the chemically modifying step may include sulfonating a portion of the inner surface of the device.

[0032] The present disclosure provides a method for fabricating a device, the method comprising: forming a device by molding or injection molding a transparent polymer; and chemically modifying a portion of the interior surface of the device to render said portion hydrophilic. The step of forming the device may further comprise separately molding two halves of the device. The chemical modification step may further comprise plasma-enhanced chemical vapor deposition (PCVD) silica or silicon oxycarbide on the molded two halves of the device, and impregnating the coated molded two halves of the device in a solution for chemical stabilization of the surface hydrophilicity. The method may also include joining the two halves together to form a coated transparent polymer device after the chemical modification step.

[0033] The present disclosure provides a method of manufacturing a device, the method comprising: forming a device by molding or injection molding a transparent polymer; and chemically modifying a portion of the surface of the device to render said portion hydrophilic. The step of forming the device may further comprise separately molding two halves of the device. The chemical modification step may further comprise plasma-enhanced chemical vapor deposition of silica or silicon oxycarbide on the two molded halves of the device. The method may also comprise, after the chemical modification step, joining the two halves to form a coated transparent polymer device. The coated transparent polymer device may be immersed in a solution for chemical stabilization of the surface hydrophilicity.

[0034] The present disclosure provides a method for fabricating a device, the method comprising: forming a device by molding or injection molding a transparent polymer; and chemically modifying a portion of the surface of the device to render said portion hydrophilic. The step of forming the device may further comprise separately molding two halves of the device. The chemical modification step may further comprise O2 plasma treatment of the molded two halves of the device and immersing the coated molded two halves of the device in a solution such as nitric acid or a cleaning solution. The method may also include joining the two halves together to form a coated transparent polymer device after the chemical modification step.

[0035] The present disclosure provides a method of fabricating a device, the method comprising: forming a device by molding or injection molding a transparent polymer; and chemically modifying a portion of the surface of the device to render said portion hydrophilic. The step of forming the device may further comprise separately molding two halves of the device. The chemical modification step may further comprise O2 plasma treatment of the molded two halves of the device. The method may include, after the chemical modification step, joining the two halves to form a coated transparent polymer device. The coated transparent polymer device may be immersed in a solution such as nitric acid or a cleaning solution.

[0036] The method for fabricating the device may further include forming the device by additive manufacturing or injection molding a transparent polymer and providing a hydrophilic layer on a portion of the interior surface of the device. The step of providing the hydrophilic layer may include reacting a first precursor, such as a silicon source, with a portion of the interior surface of the device to form a monolayer, and reacting a second precursor, such as an oxygen source, with the monolayer to form a fully reacted monolayer in one cycle. The method may repeat the cycle one or more times to control the thickness of the hydrophilic layer.

[0037] With respect to the method of manufacturing the aforementioned device, it should be noted that chemically modifying a portion of the inner surface of the transparent polymer does not reduce the transparency of the transparent polymer. In addition, the hydrophobic portion of the device (e.g., the hydrophilic layer) may be durable over ambient room temperature (e.g., from about 10°C to about 35°C, inclusive of subranges and endpoints thereof, and as a further example, from about 15°C to about 30°C). Those skilled in the art will understand that durability can be measured and demonstrated, as shown in Figure 8. For example, in addition to the above solvents, the hydrophilic portion of the device should maintain substantial hydrophilicity upon storage under ambient air (for plasma-treated hydrophilic materials, storage under ambient air may result in a greater loss of hydrophilicity than 20% aqua regia).

[0038] For example, the hydrophilic portion of the device may be resistant to solvents including 20% ​​aqua regia, dilute hydrochloric acid, nitric acid, or combinations thereof. [Example]

[0039] [Example 1] The surface hydrophilicity of a device containing sulfonated polystyrene that was freshly prepared (New Sample 1) and stored at ambient room temperature for 12 weeks (12 weeks air) is shown in Figure 2. Water contact angles were analyzed with a KRUSS DSA100W drop shape analyzer. The target surface was elevated to receive a 2.6 μL droplet of deionized water from the tip of a syringe needle. Photographs were taken by the instrument, and the contact angle between the water droplet and the surface was analyzed from the images using KRUSS ADVANCE software. The appearance and mass of the sample did not change over the storage time.

[0040] The coupon provided a flat surface for characterizing the extent or depth of any surface modification and was representative of the coating on the interior surface of the device, such as a nebulizer or atomization chamber.

[0041] [Example 2] We tested the performance of untreated (left) and chemically modified (right) transparent polymers (polystyrene) in a simulated spray chamber. As shown in Figure 3A, application of a fine aerosol caused beading on the untreated transparent polymer, while the chemically modified (sulfonated) transparent polymer possessed sufficient surface hydrophilicity to completely wet the surface and prevent any water beads from forming, as shown in Figure 3B.

[0042] [Example 3] The surface hydrophilicity of freshly prepared (New Sample 2) sulfonated polystyrene was maintained in continuous contact with 20% aqua regia for up to 14 days, as shown in Figure 4. The appearance and mass of the sample remained unchanged over the period.

[0043] [Comparative Example 1] Actual plasma-enhanced chemical vapor deposition (PECVD) silica coatings exhibited poor hydrophilicity, leading to beading of sprayed solutions within the device and static water contact angles of about 45° to about 65°. When silicon oxycarbide was the target, the hydrophobicity profile was poor (e.g., static water contact angles of about 60° to about 110°).

[0044] [Example 4] Devices containing transparent polymers with activated, highly surface-hydrophilic silica (or silicon oxycarbide) were fabricated. A Thierry plasma was used in a kilohertz plasma PECVD tool with a gas feed of hexamethyldisiloxane:O2 = 3:1. The coatings were characterized by X-ray photoelectron spectroscopy (XPS) at approximately 1-2% C, approximately 32% Si, and approximately 65% ​​O. The surface (<20 nm) was approximately 19% C, approximately 24% Si, and approximately 57% O.

[0045] The devices exhibited a static water contact angle of 60° to 70° after silica deposition by PECVD. They were then immersed (20 to 30 minutes) in a deionized water solution containing 2% commercially available "RBS-25 solution" to activate the hydrophilicity, followed by rinsing with deionized water. The devices were characterized with a static water contact angle of approximately 15°. XPS characterization showed little change in the elemental composition of the surface due to the RBS solution treatment.

[0046] In addition, transparent polymers coated with PECVD silica (or silicon oxycarbide) were able to withstand continuous contact with 20% aqua regia. Specifically, the coated coupons were exposed to ICP-OES solvents for 25 days. Figures 5A through 5C illustrate the following: Figure 5A is 20% aqua regia, Figure 5B is A-solv (kerosene) followed by 5 days of sonication in 5% Triton X-100 (sprayed water test), and Figure 5C is an example of beading water on an untreated plastic surface. As shown, transparent polymers with hydrophilic layers were able to withstand continuous contact with A-solv and 20% aqua regia. In addition, A-solv increased the static water contact angle to approximately 56° (as shown in Figure 5B), even when thoroughly rinsed with hexane. Spraying water on the surface resulted in a continuous water film rather than beading, as characterized by a receding drop static water contact angle of approximately 14°. The hydrophilicity lost upon contact with A-solv did not affect non-beading properties, and the lost hydrophilicity was restored by sonication for 30 minutes in a 5% commercially available "Extran MA02" solution or for 3 hours in 2% Triton X-100.

[0047] [Example 5] ICP-OES spray chambers are well cleaned with strong (highly alkaline and / or oxidizing) cleaning solutions under sonication. Many inorganic oxide-coated plastics deteriorate under these conditions. Coated transparent polymers have been preserved through dozens of cleaning cycles under non-etching or low-etching cleaning methods.

[0048] Transparent polymer (glycol-modified polyethylene terephthalate - PETG) coupons coated with PECVD silica were exposed to ICP-OES solvents and then sonicated in a spray chamber cleaning solution. The number of equivalent cleaning cycles was calculated by dividing the durability by the time required to eliminate the hydrophobic effect of A-solv contact (30 minutes with Extran MA02 and 3 hours with Triton X-100). The results are shown in Table 1. These results suggest that at least several dozen cleaning cycles can be performed before loss of hydrophilicity.

[0049] [Table 1]

[0050] Figure 6 shows static water contact angle measurements of PETG coupons coated with PECVD silica containing ICP-OES solvents after ultrasonic treatment in a spray chamber cleaning solution. If ultrasonic cleaning induced damage to the surface, it gradually appeared over time as ultrasonic treatment progressed, manifesting as scattered loss of the coating (appeared bright under an optical microscope (OM) after the cleaning experiment period), as shown in Figures 7A-7B. The coating loss showed no significant preference for substrate surface defects (present before coating, manifested as black lines under an OM) or coating scratches / cracks (several of which were observed, manifested as bright areas under an OM) that were present before cleaning began, suggesting the robustness of this coating method with imperfect substrates and storage / shipping / use conditions. Even with extended ultrasonic cleaning-induced coating damage and increased static water contact angles, spraying water onto the surface still resulted in a continuous water film rather than beading, as shown in Figures 5A-5B, due to the "retracted drop static water contact angle" of approximately 16°.

[0051] Figures 7A-7B are optical microscope images of PECVD silica-coated PETG coupons with ICP-OES solvents that were sonicated in a spray chamber cleaning solution. Figure 7A shows a PECVD silica-coated PETG coupon exposed to 20% aqua regia for 25 days, followed by sonication in 5% Triton X-100 for 5 days. Figure 7B shows a PECVD silica-coated PETG coupon exposed to A-solv for 25 days, followed by sonication in 5% Triton X-100 for 5 days.

[0052] [Example A] The O2 plasma treatment was applied using a kilohertz plasma PECVD tool with a gas feed of oxygen:hexamethyldisiloxane = 12:1. The hydrophilic surface was left in the activation solution for 20 minutes.

[0053] [Example 6] 500 W for 5 minutes at 400 mTorr oxygen provided performance for O2 plasma treatment of cyclic olefin polymers. For chemical stabilization of surface hydrophilicity, the surfaces were immersed in a 10% HNO3 solution at room temperature for 1 to 2 hours, rinsed with water, and air-dried for performance. Concentrated (e.g., 70% nitric acid) or stronger oxidizers (e.g., 5% ammonium persulfate) did not provide performance. Surfaces without chemical stabilization returned to their pre-O2 plasma properties within 1 to 4 weeks of storage in air and ambient conditions. As shown in Figure 8, the surface hydrophilicity of cyclic olefin polymers freshly treated with O2 plasma, followed by 10% nitric acid solution, was measured, and then stored in air (ambient room temperature) and continuously contacted with aqua regia for up to 12 weeks. The data show that the appearance and mass of the samples did not change during storage or continuous contact with aqua regia.

[0054] The performance of untreated (Figure 9A) and O2 plasma-treated cyclic olefin polymer coupons in a simulated spray chamber followed by 12 weeks of air storage (Figure 9B) was investigated. While a fine mist caused beading on the untreated cyclic olefin polymer coupons, the O2 plasma-treated cyclic olefin polymer coupons had a hydrophilic coating sufficient to completely wet the surface and prevent any bead formation. Chemical stabilization using a nitric acid solution protected the hydrophilic coating against storage under ambient air.

[0055] [Example 7] The surface hydrophilicity of glycol-modified polyethylene terephthalate samples was measured after fresh preparation (O plasma followed by 10% nitric acid), storage in air for up to 8 weeks, and contact with 20% aqua regia and A-solv (kerosene) for up to 4 days, as shown in Figure 10. The appearance and mass of the samples did not change over storage and continued contact with aqua regia or A-solv.

[0056] We investigated the performance of glycol-modified polyethylene terephthalate coupons that were untreated (Figure 11A) and that were subjected to O2 plasma treatment in a simulated spray chamber followed by 8 weeks of air storage (Figure 11B). While a fine mist caused beading on the glycol-modified untreated polyethylene terephthalate coupons, the glycol-modified O2 plasma-treated polyethylene terephthalate coupons had a hydrophilic coating sufficient to completely wet the surface and prevent any bead formation. Chemical stabilization using nitric acid solution protected the hydrophilic coating during storage under ambient air.

[0057] [Example 8] Hydrophilic layers (i.e., coatings) of SiO2 were fabricated using a vapor deposition process such as atomic layer deposition (ALD). ALD is a vapor deposition method used to fabricate thin films in a sequential layer-by-layer growth process. For ALD, the part and substrate are first placed in a vacuum and / or inert atmosphere chamber. To fabricate hydrophilic layers of SiO2 using ALD, a first precursor vapor was exposed in the vacuum chamber along with the substrate to be coated. The first silicon source precursor was Orthrus, obtained from Air Liquide. This precursor allows for the fabrication of SiO2 coatings at low temperatures, which is advantageous for coating plastics that may be adversely deformed or melted in SiO2 ALD recipes requiring higher temperatures. This precursor was used as is and heated to 50°C in the lower stage and 55°C in the upper stage in a two-stage heating jacket set.

[0058] This precursor reacted with the substrate surface, but not with itself, to form a monolayer of precursor bonded to the substrate. Excess or unreacted vapor was evacuated using an inert gas, and a second precursor was metered into the chamber. This second precursor, or co-reactant, was selected to react with the already bonded first precursor, but not with itself. Ozone, O3, was used as the oxygen source precursor. Ozone was synthesized from oxygen using a Savannah ozone generator attached to an ALD vacuum chamber tool (Savannah S300, Veeco). The chamber temperature during ALD was maintained at 50–70 °C.

[0059] After exposure to ozone, excess or unreacted vapor was evacuated from the chamber, resulting in a single, fully reacted monolayer on all surfaces within the vacuum chamber, completing one complete ALD "cycle." Each ALD cycle resulted in a newly reacted monolayer on the substrate surface, which was used to control the thickness of the deposited film. Because ALD is a gas-phase process using precursors separated by an inert gas purge step, thin films of very uniform thickness (high conformality) can be formed in very narrow grooves, holes, or other complex substrate geometries, such as the interior of a spray chamber.

[0060] Prior to SiO deposition, the plastic spray chamber substrate was loaded into the ALD chamber and allowed to pump down and warm up for 1 to 5 hours to remove moisture and gas from the spray chamber sample. After warm-up, ozone was pulsed into the chamber to activate the plastic surface and allow for chemical adhesion of the SiO precursor. This was accomplished by pulsing ozone (at a concentration of approximately 100 mg / L) for 0.2 seconds into the unpurged ALD chamber, followed by a 5-minute hold before purging with nitrogen for 20 seconds. This sequence was repeated 12 more times, resulting in a total of 60 minutes of ozone pretreatment of the plastic.

[0061] After ozone pretreatment, ALD cycling was initiated as follows. The first step of the cycle was a 0.2-second pulse of Orthrus precursor into the vacuum chamber without any vigorous pumping. The precursor remained in the chamber and reacted for 90 seconds, after which it was evacuated with high nitrogen flow and pumped out for 65 seconds. Once the chamber was purged, ozone (concentration approximately 100 mg / L) was metered into the chamber for 0.2 seconds without vigorous pumping. The ozone remained in the chamber and reacted for 300 seconds, after which it was evacuated with high nitrogen flow and vigorous pumping for 75 seconds. This sequence was repeated for approximately 225 cycles, depositing a 50-55 nm film on the substrate, as measured on silicon wafer samples by ellipsometry. Notably, the long ozone exposure time was used to maximize the combustion reaction on the growth surface, which can be difficult at these relatively low temperatures, resulting in a better SiO2 film.

[0062] Once SiO2 film deposition was complete, a final ozone activation step was performed to ensure the SiO2 film was fully reacted and maximized hydrophilicity in the final film. This was accomplished by metering ozone in 0.2-second pulses without vigorous pumping, followed by a 5-minute hold. After a 20-second purge, these steps were repeated over 24 cycles for a total ozone exposure of over 120 minutes. The entire recipe took approximately 48 hours to complete.

[0063] [Example 9] Silica water contact angle After the deposition process, sample substrates from the silicon run, which had been juxtaposed with the spray chamber during deposition, were used to test the thickness of the SiO2-deposited films using ellipsometry. These substrates, along with sample plastic coupons, were also used to test the hydrophilicity of the final films using water contact angle (WCA) measurements, as shown in Figures 12A through 12C. In the images, hydrophilicity increased (WCA decreased) with the ALD recipe changes. A relatively long ozone exposure time and an extended 120-minute ozone dosing period at the end of deposition allowed the final films to become completely hydrophilic. Figures 13A through 13C show how extended ozone exposure at the end of deposition reduced WCA.

[0064] [Example 10] Silica-coated PET spray chamber functionality results Preliminary testing of SiO2-coated PET spray chambers with ICP-OES demonstrated that sensitivity, precision, and washout tests passed within measurement standards when the spray chambers were cleaned in a 2% RBS-25 solution. Figures 14 through 16 show the results of sensitivity (Figure 14), precision (Figure 15), and washout (Figure 16) tests conducted across four separate SiO2-coated PET spray chambers and one glass cyclone spray chamber. The four SiO2-coated PET spray chambers, labeled LE12-1 through LE12-4, were initially tested after cleaning the spray chamber labeled (1) in 2% RBS-25 solution for one minute. After initial testing, the SiO2-coated PET spray chambers were retested after separate cleaning steps. The cleaning step consisted of soaking the spray chambers in a 5% Citranox solution (for samples LE12-1 and LE12-2) or a 5% Extran MA02 solution (for sample LE12-3) for 1 hour, then rinsing with DI water and resubmerging in the soak solution for a total of five cycles. LE12-4 was a control that was not cleaned in any solution. Results for the spray chambers retested after cleaning are labeled (2). As can be seen in the plot, all SiO2-coated PET spray chambers passed the 100% SRBR (signal-to-square-root background ratio) sensitivity test, and the RSD (relative standard deviation) in the precision test was less than 1% before and after cleaning. Similarly, all spray chambers passed the 0.01 ppm criterion in the washout test. The sample labeled GE was a glass cyclone spray chamber used as a reference.

[0065] As mentioned above, the experiments in Figures 14 through 16 were performed using a spray chamber cleaned with RBS-25 to facilitate cleaning and activation of the SiO2-coated surface. RBS-25 contains NaOH and NaOCl, providing a strongly basic solution (pH 13.6) that cleans and etches the SiO2 surface to make it hydrophilic. In addition, this solution may also increase the amount of surface silanol groups, which further increases hydrophilicity. The performance of the SiO2-coated PET spray chamber tested without the RBS-25 solution cleaning was not as good as the RBS-cleaned spray chamber, for example, in washout tests.

[0066] [Example 11] Silica-coated PET spray chamber stability testing The durability of SiO2-coated spray chambers against strong acids (ICP-OES solvents) and cleaning solutions is an indicator for users. Two separate tests were developed to evaluate the adhesion, cracking, and hydrophilicity of the membrane's SiO2 coating after exposure to acidic conditions similar to the ICP-OES environment and cleaning solutions that can be used to reactivate the initial operating condition of the spray chamber.

[0067] The durability tests were conducted using ALD SiO2-coated PET coupon samples juxtaposed with a PET spray chamber. The PET coupons allowed for easier evaluation of coating stability under an optical microscope. In these experiments, PET coupons were submerged in 5% HNO3 or 20% aqua regia solutions with gentle agitation. After agitation in the solutions for a set number of days, the samples were removed and cleaned for 90 minutes or more in either 5% Extran MA02 or 15% Citranox solutions before optical microscope imaging. Shown in Figures 17A through 17D are the results of coupons that underwent cleaning cycles in 20% aqua regia agitation and 5% Extran MA02 solutions. In the images, large, dark scratches are from the plastic and not part of the film. In Figures 17A and 17B, sample LE16-C11 shows only deep, dark scratches, suggesting that the film was still intact. However, in Figure 17C, sample LE10-C1 exhibits microcracks throughout its surface, suggesting that the thin film had cracked and potentially delaminated from the plastic surface. The SiO2 film prepared for sample LE10-C1 did not include ozone pretreatment, potentially weakening the film's adhesion to the PET plastic and making it more susceptible to cracking. The 30-minute ozone pre-exposure of sample LE16-C11 activates the PET surface, allowing for better chemical bonding of the SiO2 ALD layer. The film survived for 47 days in 20% aqua regia, including nine cycles, equivalent to approximately six months of customer use (based on 8 hours of use per business day and monthly cleaning). Compared to Figure 17D (5 days of exposure to 20% aqua regia and cracking and delamination before any cleaning), the ALD coating with ozone pretreatment also exhibits much better durability.

[0068] [Example 12] Silica coated on the inner surface of the PET spray chamber The SiO2-coated PET spray chamber was tested using ICP-OES nebulization parameters by atomizing 5% HNO3 (1.0 mL / min) into the spray chamber via a peristaltic pump with house N2 (0.7 L / min). The spray chamber was placed under an acid drain sink, and water colored with blue food coloring was passed over the interior surface of the spray chamber for visual analysis of water beading. For safety concerns, the spray chamber was covered with a beaker to capture atomized droplets and prevent them from leaking out of the sink, and the sink was completely covered with a clear acrylic cover when not being tested.

[0069] Long-term testing was conducted using this spray chamber setup under near-real-world conditions. After spraying 5% HNO3 via a nebulizer and SiO2-coated PET spray chamber setup for several days, visual inspection of water beading was performed by temporarily switching to a blue-colored aqueous solution. The results are shown in Figures 18A through 18E. Figure 18A shows no visible beading of blue water droplets after 7 days of HNO3 flow and two cleaning cycles in a 15% Citranox solution. When the same test was repeated after 10 days of standing at ambient air conditions, some beading began to appear on the interior surface (Figure 18B). The hydrophilicity returned after cleaning with 5% Extran MA02 (Figure 18C). The hydrophilicity was maintained for a total of at least 46 days of HNO3 spraying and eight 15% Citranox cleaning cycles (equivalent to approximately six months of customer use) (Figure 18C). For comparison, another spray chamber that has lost most of its hydrophilicity is shown in Figure 18E, but exhibits very large droplets. Spray chambers exhibiting significant beading, such as that shown in Figure 18E, result in overall reduced sensitivity, precision, and washout compared to those with a hydrophilic layer.

[0070] From the foregoing description, those skilled in the art will appreciate that the present teachings may be embodied in a variety of forms. Thus, while these teachings have been described with reference to specific embodiments and examples thereof, the true scope of the present teachings should not be so limited. Various changes and modifications can be made without departing from the scope of the teachings of the present disclosure.

[0071] The scope of the present disclosure is to be construed broadly. The present disclosure is intended to disclose equivalents, means, systems, and methods for achieving the devices, acts, and mechanical functions disclosed herein. For each device, article, method, means, mechanical element, or mechanism disclosed, the present disclosure is also intended to encompass within its disclosure and to teach equivalents, means, systems, and methods for implementing the many aspects, mechanisms, and devices disclosed herein. The scope of the claims of this application is likewise to be construed broadly. Because the description of the invention herein in its many embodiments is merely exemplary in nature, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be considered as departing from the spirit and scope of the invention.

Claims

1. 1. A device for an inductively coupled plasma device, comprising a hydrophilic layer on a portion of an inner surface of a transparent polymer forming a body, said hydrophilic layer being formed by a sulfonated inner surface of said transparent polymer, silica, silicon oxycarbide, O of said transparent polymer. ２ plasma treated, or a combination thereof, wherein the transparent polymer is polystyrene, polyethylene terephthalate with glycol modifications, polyethylene terephthalate, cyclic olefin polymer, or polycarbonate.

2. The device of claim 1 , wherein the transparent polymer is polystyrene.

3. The device of claim 1 , wherein the hydrophilic layer is the sulfonated inner surface of the transparent polymer.

4. The device of claim 1 which is disposable.

5. The device of claim 1 , wherein the hydrophilic layer is silica or silicon oxycarbide.

6. 10. The device of claim 1, wherein the transparent polymer is polyethylene terephthalate or polyethylene terephthalate with a glycol modification.

7. The device of claim 1 , wherein the transparent polymer is a cyclic olefin polymer.

8. The hydrophilic layer is made of the transparent polymer ２ The device of claim 1 which is plasma treated.

9. The device of claim 1 which is a nebulization chamber.

10. The device of claim 1 which is a nebulizer.

11. A method of manufacturing a device for an inductively coupled plasma device, comprising: forming a device by molding or injection molding a transparent polymer; chemically modifying a portion of the interior surface of the device, the portion being rendered hydrophilic; wherein the transparent polymer is polystyrene, polyethylene terephthalate with glycol modifications, polyethylene terephthalate, cyclic olefin polymer, or polycarbonate.

12. The method of claim 11 , wherein the chemically modifying step comprises sulfonating a portion of the inner surface of the device.

13. The method of claim 11 , wherein the hydrophilic portion of the device is durable for storage in air at room temperature.

14. 12. The method of claim 11, wherein the hydrophilic portion of the device is resistant to solvents including 20% ​​aqua regia, dilute hydrochloric acid, nitric acid, or combinations thereof.

15. forming the device, separately molding the two halves of the device; joining the two halves together to form the transparent polymer device; The method of claim 11 further comprising:

16. the chemically modifying step comprising: immersing the formed transparent polymer device in a sulfuric acid bath. The method of claim 11 further comprising:

17. forming the device, separately molding the two halves of the device; and further comprising, after said chemically modifying step, joining said two halves together to form said device. The method of claim 11.

18. 12. The method of claim 11, wherein the chemically modifying step comprises applying sulfuric acid at a temperature ranging from -5°C to less than 80°C for a time ranging from 1 minute to 1 hour.

19. 19. The method of claim 18, wherein the concentration of the sulfuric acid is at least 96%.

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