Evaporation trap for single and multi-channel pipettes

Abstract

It is provided an evaporation trap device for pipetting. The device is compatible with both single-channel and multi-channel pipettes and can be used in a fully automated lab environment without human interaction. The device enables faster iterations and better performance compared to existing solutions. It provides more accurate measurement capabilities and enhanced multi-channel pipetting functionality. The improved evaporation trap device incorporates a housing member with two side water wells and an opening on the exterior of said housing, a center water well located inside said housing, and a water reservoir situated inside said housing and having an exposed top water surface for evaporation.

Description

EVAPORATION TRAP FOR SINGLE AND MULTI-CHANNEL PIPETTESTECHNICAL FIELD

[0001] This disclosure relates to lab equipment, specifically evaporation traps commonly used in labs in tandem with analytical balances to minimize the evaporation of the liquid being measured.BACKGROUND

[0002] Evaporation traps have been used on top of analytical balances to minimize the evaporation of the liquid being measured inside laboratories. The evaporation of the specimen is minimized by having a reservoir of water with much larger surface area to quickly equilibrate the humidity to 100% inside the trap. In addition, a removable lid at the top only opens up during liquid dispensing and closes when measuring, further preventing the water vapor from escaping. Existing evaporation traps are predominantly configured to work with single channel pipettes, and designed to be operated by a lab technician.SUMMARY

[0003] The present invention provides an evaporation trap device for pipetting. The device is compatible with both single-channel and multi-channel pipettes and can be used in a fully automated lab environment without human interaction. The device enables faster iterations and better performance compared to existing solutions. It provides more accurate measurement capabilities and enhanced multi-channel pipetting functionality. The improved evaporation trap device incorporates a housing member with two side water wells and an opening on the exterior of said housing, a center water well located inside said housing, and a water reservoir situated inside said housing and having an exposed top water surface for evaporation.

[0004] These and other features of the disclosure will become apparent to those skilled in the art from the following detailed description of the disclosure, taken together with the accompanying drawings.BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1 depicts one embodiment of the evaporation trap of the present disclosure placed on top of an analytical balance.

[0006] Figure 2 depicts an exploded view of the evaporation trap in Figure 1 including the analytical balance.

[0007] Figure 3 depicts a close-up view of the evaporation trap in Figure 1.

[0008] Figure 4 depicts the lid of the evaporation trap in Figure 1 in the closed position and operated by a single-channel pipette.

[0009] Figures 5 depicts an exploded view of the center water well of the evaporation trap in Figure 3.

[0010] Figure 6 depicts another embodiment of the cleaning member of the center water well in Figure 5.

[0011] Figure 7A depicts a front view of the housing of the evaporation trap in Figure 1.

[0012] Figure 7B depicts a cutout section view of the housing in Figure 7 A.

[0013] Figure 8 depicts a partially cutout view of the evaporation trap in Figure 1 showing a multi-channel pipette dispensing into the center water well.

[0014] Figure 9 depicts another embodiment of the evaporation trap of the present disclosure placed on top of an analytical balance.

[0015] Figure 10 depicts an exploded view of the evaporation trap in Figure 9 including the analytical balance.DETAILED DESCRIPTION

[0016] The present disclosure is an evaporation trap for single and multi-channel pipettes. The evaporation trap functions by incorporating a center water well for pipettes to dispense liquid into, placed on top of the balance pan of an analytical balance. A housing with a lid surrounds the center well to isolate it during measurement from the environment, preventing factors such as wind from affecting the reading. The housing contains an additional water reservoir on the inside. The water reservoir encircles the center water well but maintains separation to avoid affecting the measurement. The water reservoir's top remains exposed to enable water evaporation. The water evaporated from the water reservoir equilibrates the humidity inside the housing and prevents the liquid in the center well from evaporating and producing an inaccurate measurement. The lid on the top of the housing opens during dispensingand closes during measurement. Figure 1 depicts one embodiment of the evaporation trap of the present disclosure.

[0017] Referring to Figure 1, the evaporation trap 1000 of the present disclosure is positioned on top of an analytical balance 2000. The analytical balance 2000 consists of the balance main body 2100 and a base plate 2200 placed on top of the balance 2100 underneath the evaporation trap 1000. The material of the base plate 2200 can be plastic or metal, preferably anti-static to reduce static effect on the measurement. The evaporation trap 1000 consists of a main housing 1100, two side water wells 1110a and 1110b, a center water well 1200 placed inside housing 1100, two aligning members 1400a and 1400b, and a lid 1300 in its open position. The lower portion of a multi-channel pipette 3000 includes twelve pipette tips 3100.

[0018] The evaporation trap in Figure 1 is in the dispensing state, where the lid 1300 is rotated to the open position, and the multi-channel pipette 3000 dispenses liquid into both the center water well 1200 and the side water well 1110b. The ISO 8655:2022 requirements for pipette calibration stipulate that all channels of a multi-channel pipette must be dispensed in parallel. The leftmost pipette tip 3100 dispenses water into the center water well, and the analytical balance measures the amount. The other eleven pipette tips 3100 dispense into the side water well 1110b, and this amount remains unmeasured. This process is repeated for all pipette tips 3100 in a multi-channel pipette 3000. This represents an improvement over existing multichannel pipette calibration analytical balances, which typically involve specialized balances with multiple load cells that cannot be used for other applications. The embodiment 1000 can be installed onto any conventional analytical balance.

[0019] Referring now to Figure 2, there may be seen an exploded view of the evaporation trap 1000 in Figure 1. The analytical balance 2000 consists of the balance main body 2100, a base plate 2200, and a balance pan 2300. The evaporation trap consists of a center water well 1200, a housing 1100, two aligning members 1400, and a rotary lid 1300. The rotary lid incorporates a hinge 1308 that enables rotation between a closed position for measuring and an open position for dispensing liquid. The center water well 1200 includes a mating ring 1210 to securely connect to the balance pan 2300. The base plate 2200 incorporates a locating mechanism 2202 for secure connection to the housing 1100, preventing the housing 1100 from moving and contacting the center water well. The base plate 2200 matches the top shape of the analytical balance body 2100, enabling secure placement without movement. The base plate 2200 includes a center opening for balance pan 2300 passage. The base plate 2200 further incorporates outside wall 2204 and inside wall 2206. These walls configure the base plate 2200 as a shallow container that captures accidentally spilled liquid, preventing equipment damage.

[0020] Referring now to Figure 3, there may be seen a close-up view of the evaporation trap in Figure 1. More specifically, the evaporation trap 1000 consists of a housing 1100, a center water well 1200, a rotary lid 1300, and an aligning member 1400. The housing member 1100 comprises a wall 1101, a water dispensing opening 1102, a water line indicator 1104, four screw holes 1106 (two hidden under aligning member 1400), a center opening 1108 for center water well 1200 access, two elongate side water wells 1110, a conduit 1112 connecting the two side water wells 1110, two conduit end openings 1114 into the side water well 1110 (one end opening hidden behind aligning member 1400), two slope features 1116 around the center opening 1108 (one partially obscured due to viewing angle), and a key hole 1160 for rapid location identification by a robotic arm.

[0021] The rotary lid 1300 incorporates a slot- shaped contact bump 1302, a roundshaped contact bump 1304, a thin beam member 1306, a hinge 1308 for rotation, and a cutout indent 1310 for attaching a sealing pad. The aligning member 1400 includes four aligning slots 1402 and two screw holes 1404. The screw holes 1404 align with the screw holes 1106 for securing the aligning member to the housing 1100. The aligning slots 1402 feature a tapered profile, enabling automatic centering of pipette tips 3100 when they move downward through the slots, compensating for slight misalignment due to hand movement or robotic arm positioning errors. The slopes 1116 serve to center the pipette tips, preventing contact between the measured tip and the opening 1108 rim, ensuring complete liquid dispensation into well 1200 for measurement.

[0022] Continuing to refer to Figure 3, opening 1102 connects to the internal water reservoir. The water line indicator 1104 provides guidance for proper filling levels, minimizing overflow risk. The conduit 1112 linking the two side water wells 1110a and 1110b ensures equal water levels in both wells, accommodating varying dispensation amounts from the multi-channel pipette.

[0023] Referring now to Figure 4, there may be seen a side view of the evaporation trap operated by a single channel pipette 4000 and its pipette tip 4100. The rotary lid 1300 occupies a closed position, covering the housing 1100. The rotary lid 1300 incorporates a slot-shaped contact bump 1302, a round-shaped contact bump 1304, a thin beam member 1306, a wide beam member 1307, and a hinge 1308 for rotation. The rotary lid 1300 design enables operation via pipette 4000. To open the lid for dispensing, the pipette 4000 moves in direction DI, allowing pipette tip 4100 to contact the round-shaped bump 1300 gently, gradually rotating the lid 1300 open. The beam 1306 maintains sufficient narrowness to prevent contact between the pipette tip 4100 lower bottom and any part of the rotary lid 1300 during movement.

[0024] To close the rotary lid from the open position shown in Figure 1, the motion reverses, with pipette 4000 contacting the slot-shaped bump 1302 and moving opposite to direction DI. The beam 1307 requires greater width than beam 1306 to adequately cover the evaporation trap's top opening. This necessitates configuring bump 1302 as slot-shaped to extend it and prevent contact between the pipette tip 4100 lower bottom and the rotary lid 1300. Alternative embodiments may incorporate motorized rotation, eliminating the need for pipettelid contact.

[0025] Referring now to Figure 5, there may be seen an exploded view of the center water well 1200 shown in Figure 2. The center water well 1200 consists of a mating ring 1210, a water containing member 1220, and an optional cleaning member 1230. The mating ring 1210 incorporates a center opening 1212 for secure connection to the water containing member 1220. The water containing member 1220 features a wide opening 1224 and narrow opening 1226 on top, containing water 1222 inside. The narrow opening 1226 accommodates multi-channel pipette tips, which typically handle small volumes and maintain 9mm spacing. The wide opening 1224 accommodates larger single channel pipettes capable of dispensing up to 10 ml.

[0026] The cleaning member 1230 mounts atop the water containing member 1220, functioning to remove water droplets from pipette tips after dispensing, ensuring complete water collection inside the water containing member 1220 for accurate measurement. The cleaning member 1230 incorporates a wide flap 1232 and a narrow flap 1234 corresponding to openings 1224 and 1226.

[0027] The flaps 1232 and 1234 comprise soft materials that deform angularly upon pipette tip insertion, maintaining consistent contact with the tip bottom during dispensing. This design mimics the standard laboratory technique of angling pipettes against glassware walls during dispensing to prevent droplet formation. The cleaning member 1230 design enables vertical pipette orientation, facilitating robotic arm operation in automated calibration systems. Post-dispensing, upward pipette movement allows the flaps 1232 and 1234 to return to their original positions. The cleaning member 1230 should be elastic and soft for durability, utilizing materials such as TPU, thin plastic strands similar to toothbrush bristles, silicone rubber, or thin metal strands.

[0028] Referring to Figure 6, an alternative embodiment 1240 of the cleaning member 1230 replaces flaps 1232 and 1234 with small bristle members 1242 for post-dispensing liquid removal from pipette tips.

[0029] Figure 7A depicts a front view of the housing 1100 of the evaporation trap 1000 in Figure 1. Figure 7B depicts a cutout section view of the housing in Figure 7A.

[0030] Referring now to Figure 7B, the housing 1100 comprises wall 1101, water dispensing opening 1102, opening 1108 in side view, side water well 1110a interior, conduit 1112 cross section, locating feature 1118, water reservoir 1120 cross section, reservoir water 1122, top reservoir opening 1124, and rotary lid 1300 hinge 1308 in side view. The locating feature 1118 functions in conjunction with base plate 2200 locating feature 2202. Reservoir opening 1124 facilitates rapid water 1122 evaporation for internal humidity equilibration. Water dispensing opening 1102 enables external reservoir filling.

[0031] Referring now to Figure 8, there may be seen a view of the evaporation trap 1000 working in action, with the housing 1100 in partially cutout view. More particularly, the assembly includes side water well 1110a containing water 1111, conduit 1112, conduit water 1118, water reservoir 1120, reservoir water 1122, reservoir opening 1124, center water well water containing member 1220, cleaning member 1240, multi-channel pipette 3000, twelve pipette tips 3100, four aligning slots 1402, and a partially cut away rotary lid 1300. Water 1118 maintains connectivity with water 1111. Four pipette tips 3100 pass through the aligning slots to access water 1111, while the alignment system ensures precise positioning of the rightmost pipette tip 3100 into center water well 1200 without housing contact. The rightmost pipette tip penetrates cleaning member 1240 for dispensing and retracts upward for cleaning postdispensation.

[0032] Referring now to Figure 9, there may be seen another embodiment of the evaporation trap 5000 of the present disclosure placed on top of an analytical balance 2000. More particularly, the analytical balance 2000 consists of balance main body 2100 and base plate 2200 positioned between balance 2100 and evaporation trap 5000. The evaporation trap 5000 comprises main housing 5100 containing dispense well 5200 (not visible), trap cover 5300, and resistance temperature detector (RTD) 5400. The RTD 5400 monitors water temperature inside the trap to facilitate water density calculations.

[0033] Referring now to Figure 10, there may be seen an exploded view of the analytical balance 2000 and the evaporation trap 5000. More particularly, the analytical balance 2000 consists of balance main body 2100, base plate 2200 incorporating locating mechanism 2202, and balance pan 2300. The evaporation trap 5000 comprises center water well 5200, housing 5100, trap cover 5300, RTD 5400, and RTD lid 5500. Unlike the first embodiment, center water well 5200 directly contacts balance pan 2300 without a mating ring. Similar to center water well 1220, center water well 5200 incorporates a narrower section 5210 for smaller and multi-channel pipettes 3000, a wider section 5220 for larger and single-channel pipettes 4000, and locating spokes 5230.

[0034] Main housing 5100 rests by gravity on base plate 2200. Center water well 5200 occupies well cavity 5130 within main housing 5100, with locating spokes 5230 suspended above matching internal grooves 5150 (one visible). Main housing 5100 maintains separation from center water well 5100 and balance pan 2300 to prevent measurement interference. The locating spokes 5230 enable position recovery when center water well 5200 contacts the main housing 5100 wall; users can elevate main housing 5100 slightly to align locating spokes 5230 with internal grooves 5150, resetting center water well 5100 position. After zeroing, lowering main housing 5100 re-establishes center water well 5200 isolation. Alternative zeroing methods include external centering tools or visual alignment. The locating spokes 5230 also ensure simultaneous removal of center water well 5200 when lifting main housing 5100, reducing accidental spillage risk onto balance main body 5100.

[0035] Continuing to refer to Figure 10, main housing 5100 further includes side wells 5110a and 5110b, reservoir water 1122, RTD hole 5140, and RTD lid 5500. Trap cover 5300 mounts atop main housing 5100, incorporating narrower hole 5310 matching center water well narrower section 5210, wider hole 5320 matching wider section 5220, and aligning members 5330 with slopes for multi-channel pipette tip alignment during descent into narrower hole 5310. RTD hole 5140 either connects to reservoir water 1122 or contains separate water for RTD 5400 measurement. RTD lid 5500 controls water evaporation rate within RTD hole 5400 to maintain measurement accuracy.

[0036] The dispense well 5200 should be conductive and anti-static, preferably metallic, to prevent static force generation from proximity to main housing 5100 internal walls. Trap cover 5300 may attach to main housing 5100 via gravity, removable snap fits, fasteners, or magnets. The current embodiment's trap cover 5300 features two openings - narrower hole 5310 and wider hole 5320 - permitting gradual moisture escape. While this rate may suffice for fivedigit analytical balance stabilization, six-digit analytical balances may require complete opening coverage. Optional motorized flaps can provide complete closure. Alternatively, narrower hole 5310 and wider hole 5320 may incorporate flexible materials with slit cutout 5322, expanding upon pipette tip insertion and closing upon retraction.

[0037] While this disclosure describes specific embodiments, it does not limit itself to these configurations. Accordingly, other embodiments, variations, and improvements not described herein remain within the disclosure's scope. Such variations include but are not limited to modified water well shapes, alternative water reservoir designs, varying numbers of openings, novel cleaning member materials, and housing modifications accommodating different commercial analytical balance designs.

[0038] Although this disclosure and its advantages have been described in detail, various changes, substitutions, and alterations can be implemented without departing from the disclosure's spirit and scope as defined by the appended claims.

Claims

CLAIMS1. An evaporation trap for pipetting, comprising: a housing member having two side water wells and an opening on the exterior of said housing, a center water well located inside said housing and inside said opening, and a water reservoir situated inside said housing and having an exposed top water surface for evaporation.

2. The evaporation trap for pipetting of claim 1, further comprising: a cover member installed on the exterior of said housing and above said opening, movable between a first position that covers up said opening and a second position that leaves said opening exposed.

3. The evaporation trap for pipetting of claim 1, further comprising: a cover member installed atop of said housing and said opening, having at least one smaller hole than said opening to restrict said center water well and said water reservoir evaporation rate.

4. The evaporation trap for pipetting of claim 1, further comprising: a cover member installed atop of said housing and said opening having at least one flexible slit or flap that can be pushed open by a pipette tip when dispensing and rebound when said pipette tip is retracted to restrict said center water well and said water reservoir evaporation rate.

5. The evaporation trap for pipetting of claim 1, further comprising: at least one aligning member attached to the exterior of said housing to allow for centering pipette tips as they go downward into said side water wells and said center water well.

6. The evaporation trap for pipetting of claim 1, further comprising: a base member located underneath said housing to allow for stable connection between said housing and a balance.

7. The evaporation trap for pipetting of claim 6, wherein said base member has walls to contain spilled water and prevent water damage to said balance.

8. The evaporation trap for pipetting of claim 1, wherein said housing member further comprises: a second opening on the exterior of said housing that allows for refilling of said water reservoir from the outside of said housing.

9. The evaporation trap for pipetting of claim 1, wherein said housing member further comprises: a conduit that connects the two said water wells together for water level synchronization.

10. The evaporation trap for pipetting of claim 1, wherein said center water well further comprises: a cleaning member located on top of said center water well to remove water droplets stuck onto pipette tips after ejection.

11. The evaporation trap for pipetting of claim 1, wherein said center water well further comprises: an interfacing member located underneath said center water well to allow for secure connection between said center water well and a balance pan of an analytical balance.

12. The evaporation trap for pipetting of claim 1, wherein the top opening of said center water well is split into a narrower section for smaller pipette tips and multi-channel pipettes, and a wider section for larger pipette tips.

13. The evaporation trap for pipetting of claim 1, wherein the shape of said center water well configures a narrower section for smaller pipette tips and multi-channel pipettes, and a wider section for larger pipette tips.

14. The evaporation trap for pipetting of claim 2, wherein said lid member is motorized.

15. A water container for pipetting, comprising : an opening on the top of said water container for pipette tips to go through, and at least one flexible slit or flap that can be pushed open by a pipette tip when dispensing and rebound when said pipette tip is retracted to restrict said water container evaporation rate.

16. An evaporation trap for pipetting, comprising: a housing member having two side water wells and an opening on the exterior of said housing, a center water well located inside said housing and inside said opening, a water reservoir situated inside said housing and having an exposed top water surface for evaporation, a cover member installed atop of said housing and said opening having at least one smaller hole than said opening to restrict said center water well and said water reservoir evaporation rate.

17. An evaporation trap for pipetting, comprising: a housing member having two side water wells and an opening on the exterior of said housing, a center water well located inside said housing and inside said opening having a narrower section for smaller pipette tips and multi-channel pipettes, and a wider section for larger pipette tips, a water reservoir situated inside said housing and having an exposed top water surface for evaporation, and a cover member installed atop of said housing and said opening.

18. An evaporation trap for pipetting, comprising: a housing member having two side water wells and an opening on the exterior of said housing, a center water well located inside said housing and inside said opening, a water reservoir situated inside said housing and having an exposed top water surface for evaporation, a cover member installed on the exterior of said housing and above said opening movable between a first position that covers up said opening and a second position that leaves said opening exposed, and a base member located underneath said housing to allow for stable connection between said housing and a balance.

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