JP2006223944A - Dispensing component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dispensing component in which the volume variation of a liquid to be dispensed can be restrained even when the meniscus curvature of the liquid varies. <P>SOLUTION: The dispensing component 1 for discharging the whole of the liquid held therein at a time by utilizing a compressed gas is provided with: an opening formed in the upper part thereof; a measurement part 1a which has a fixed volume of space communicated with the opening and in which the liquid to be packed in the space is measured/held by utilizing the volume defined by the gas-liquid interface M formed in the opening and the space; and a discharge flow passage 1b which is communicated with the measurement part oppositely to the opening and is used for discharging the liquid held in the measurement part when the pressure of the compressed gas is exerted on the liquid. The length Lm in the discharge direction of the liquid is set longer than the length Dm in the direction perpendicular to the discharge direction in the cross section along the central axis Ac of the metering part 1a so that the volume variation of the liquid to be measured and held in the measurement part, which is generated owing to the variance of the gas-liquid interface, can be restrained. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a dispensing component used for dispensing a liquid of nanoliter (nL) to microliter (μL) order.

  Conventionally, as a dispensing device that discharges and dispenses a small amount of liquid in the order of nL to μL with pressurized gas, a liquid outlet that is carried from a reservoir through a flow path has a pair of openings facing each other, and the liquid Is known that is held between the pair of openings by surface tension (see, for example, Patent Document 1).

JP-T-2002-509023

  Incidentally, in the dispensing device disclosed in Patent Document 1, the liquid Lq is held between the upper and lower openings O by surface tension, as shown in FIG. At this time, the liquid Lq held between the upper and lower openings O has the upper and lower portions missing due to the recesses caused by the meniscus (gas-liquid interface) compared to the geometric shape defined by the upper and lower openings. End up. The curvature of the meniscus of the liquid Lq generally changes depending on the difference in the surface tension of the liquid Lq related to the type and concentration of the solute.

  Therefore, in FIG. 18 in which the upper part of the liquid Lq is enlarged, the radius of the meniscus M is rmm, the contact angle with the wall surface of the liquid Lq in the opening O is θ °, and the missing volume ΔV of the liquid Lq that is missing by the concave portion of the meniscus M. When the relationship between (nL) and the diameter (mm) of the opening O is calculated for each contact angle θ = 75 °, 80 °, and 85 ° within a range of 0.05 to 1 mm in diameter of the opening O, FIG. The results shown are obtained. As is clear from this result, for example, when the contact angle changes by ± 5 ° with reference to the contact angle θ = 80 °, the missing volume ΔV of the liquid Lq changes by ± 49% at the maximum. Therefore, in the dispensing device of Patent Document 1, since the liquid missing volume ΔV is generated in the upper and lower portions due to the meniscus existing above and below, the volume of the liquid to be ejected is the surface tension based on the difference in the density and viscosity of the liquid. There was a problem of large variation due to the difference in meniscus curvature caused by the difference.

  This invention is made | formed in view of the above, Comprising: It aims at providing the dispensing component which can suppress the dispersion | variation in dispensing volume even if meniscus curvature differs.

  In order to solve the above-described problems and achieve the object, the dispensing component according to claim 1 is a dispensing component that discharges the entire amount of the held liquid at one time using pressurized gas, It has an opening to be formed and a space of a certain volume connected to the opening, and is filled into the space by utilizing a volume defined by the gas-liquid interface formed in the opening and the space. A metering unit for metering and holding the liquid, and being connected to the metering unit so as to face the opening, and held by the metering unit when the pressure of the pressurized gas is applied to the liquid. A discharge channel for discharging the liquid, and a central axis of the measuring unit so as to suppress variation in the volume of the liquid measured and held in the measuring unit caused by a difference in the gas-liquid interface. How to discharge the liquid in a cross section along The length of the is characterized in that it is set larger than the length in the direction orthogonal to the ejection direction.

  According to a second aspect of the present invention, in the above-described dispensing part, the measuring unit is configured such that the length Lm in the liquid discharge direction in the cross section is 2Dm < It is characterized by being set in the range of Lm <10 Dm.

  Further, in the dispensing component according to claim 3, in the above invention, the discharge flow path is set such that a length d in a direction orthogonal to the liquid discharge direction is smaller than a length Dm of the measuring portion. It is characterized by that.

  In the dispensing component according to the present invention, the discharge channel for guiding the liquid is connected to the measuring unit, and the length of the measuring unit in the liquid discharging direction is set larger than the length in the direction perpendicular to the discharging direction. Compared with the volume of the liquid held in the measuring unit, the missing volume becomes a very small amount, and there is an effect that variation in dispensing volume due to a difference in meniscus curvature can be suppressed.

(Embodiment 1)
Hereinafter, Embodiment 1 concerning the dispensing components of this invention is demonstrated in detail, referring drawings. FIG. 1 is a cross-sectional perspective view showing one structural unit of a dispensing part. FIG. 2 is a sectional front view of the dispensing component.

  As shown in FIG. 1, the dispensing component 1 includes a measuring unit 1 a and a discharge channel 1 b as one constituent unit for liquid discharge, and uses one constituent unit or one constituent unit depending on the purpose. A plurality of linear or matrix arrangements are used. The dispensing component 1 dispenses the liquid by collectively ejecting the entire nL to μL-order liquid held in the metering unit 1a from the discharge channel 1b with pressurized gas that acts from above the metering unit 1a. The measuring unit 1a has an opening formed in the upper part and a space of a constant volume connected to the opening, and is a cylindrical part that measures liquid of nL to μL order. The measuring unit 1a is filled with a liquid to be dispensed by a method such as dropping a liquid from above or contacting the tip of a micropipette. At this time, the metering unit 1a holds a predetermined amount of liquid by filling the liquid up to the opening on the upper surface. The discharge channel 1b is connected to the measuring unit 1a and discharges the liquid held in the measuring unit 1a from the lower end. As shown in FIG. 2, the dispensing component 1 has a length Lm in the discharge direction of the liquid Lq in the cross section along the central axis Ac of the measuring portion 1a. Also set larger.

  Here, when the dispensing part 1 is filled with the liquid in the measuring part 1a, the liquid in the measuring part 1a enters due to the capillary force, and as shown in FIG. 2, the upper part of the measuring part 1a and the lower part of the discharge channel 1b A meniscus of the liquid Lq is formed on each. In this case, the measuring unit 1a only has the meniscus M of the liquid Lq formed on the upper part. For this reason, the measuring unit 1a has half the missing volume due to the meniscus as compared with the dispensing device of Patent Document 1 in which the liquid Lq is held between the upper and lower openings O. Moreover, in the measuring unit 1a, the length Lm in the discharge direction of the liquid Lq is set larger than the diameter Dm that is the length in the direction orthogonal to the discharge direction (Lm> Dm). Therefore, in the measuring unit 1a, the missing volume due to the meniscus becomes a minute amount compared to the volume of the liquid to be held, and the dispersion of the dispensed volume due to the difference in meniscus curvature can be suppressed.

  At this time, the measuring unit 1a more preferably sets the length Lm in the discharge direction of the liquid Lq in a range of 2Dm <Lm <10Dm. When the length Lm is smaller than twice the diameter Dm, the measuring unit 1a has a problem that the missing volume of the liquid due to the difference in meniscus curvature increases and the variation in the amount of liquid retained increases. On the other hand, when the length Lm exceeds 10 times the diameter Dm, the measuring part 1a has a longer molding pin for molding the measuring part 1a when molding by injection molding or the like, and the molding pin is easily broken during molding. There is a problem of becoming. Most preferably, the length Lm in the discharge direction of the liquid Lq is set to a range of Lm≈2Dm to 3Dm.

  On the other hand, the discharge channel 1b is a channel for discharging the liquid held in the measuring unit 1a, and is not a part for holding the liquid. For this reason, as shown in FIG. 2, the dispensing component 1 has a discharge flow so that a predetermined amount of liquid designed in advance is always stably discharged even if the liquid Lq enters the discharge flow path 1b. It is desirable to set the volume v of the liquid Lq in the channel 1b to be a very small amount (V >> v) compared to the volume V of the liquid Lq held in the measuring unit 1a. Accordingly, as shown in FIGS. 2 and 3, the dispensing component 1 sets the inner diameter df of the discharge flow path 1b to be smaller than the inner diameter Dm of the measuring portion 1a (df <Dm) and extends in the longitudinal direction. The length Lm is set longer than the length Lf of the discharge channel 1b (Lm> Lf). As described above, the dispensing component 1 that discharges liquid in the order of nL to μL is formed by, for example, etching a silicon substrate or injection molding or the like, such as polycarbonate, polypropylene, acrylic, cycloolefin copolymer (COC), cycloolefin polymer ( COP) and the like can be produced by molding.

  Here, the dispensing component 1 shown in FIGS. 1 to 3 has a large change in cross-sectional area (rapid contraction) at the connecting portion between the measuring portion 1a and the discharge flow path 1b, and a large energy loss is caused in the discharged liquid. Arise. For this reason, as shown in FIG. 4, the dispensing component 1 has a curved portion 1e at the lower portion of the measuring portion 1a so that the inner diameter of the lower portion of the measuring portion 1a connected to the discharge passage 1b gradually decreases toward the discharge passage 1b. It is preferable to mold it. At this time, as shown in FIG. 5, the dispensing part 1 has a conical shape at the lower part of the measuring part 1a so that the inner diameter of the lower part of the measuring part 1a connected to the discharge flow path 1b gradually decreases toward the discharge flow path 1b. Or you may shape | mold to the pyramid-shaped taper surface 1f. Further, when the resistance of the discharge channel 1b is reduced by applying hydrophobic processing, the liquid is easily discharged.

  On the other hand, as shown in FIG. 6, the dispensing component 1 has a tapered surface 1g having a conical or pyramidal shape in which the diameter of the entire measuring portion 1a decreases toward the discharge flow path 1b, and the discharge flow path 1b is also located on the inner side. The outer diameter may be formed slightly larger. In this case, as shown in FIG. 7, the dispensing component 1 is resin-molded using an upper mold 11 and a lower mold 12 having a convex portion 12a corresponding to the discharge flow path 1b. Further, as shown in FIG. 8, the dispensing component 1 may be resin-molded using an upper mold 11 having a convex portion 11a corresponding to the discharge flow path 1b and a lower mold 12. Is formed with a discharge channel 1b having an inner diameter slightly larger than the outer diameter. Furthermore, as shown in FIG. 9, the dispensing part 1 may be resin-molded using an upper mold 11 and a lower mold 12, and the discharge flow path 1b is formed by machining or laser machining after molding. Form.

  As described above, the dispensing component 1 has a discharge channel for discharging the liquid connected to the measuring unit, and the length Lm of the measuring unit 1a in the discharge direction of the liquid Lq is a length perpendicular to the discharge direction. It was set larger than a certain diameter Dm (Lm> Dm). Accordingly, the dispensing component 1 has a small missing volume compared to the volume of the liquid held in the measuring unit 1a, and even if the meniscus curvature is different, variation in the discharged liquid amount can be suppressed. Liquid can be discharged.

(Embodiment 2)
Next, a second embodiment according to the dispensing component of the present invention will be described. In the dispensing part of the first embodiment, the measuring unit 1a and the discharge channel 1b exist on the same central axis Ac. However, the dispensing part of the second example has the central axis and the discharge channel of the measuring unit. The center axis of is offset. FIG. 10 is a cross-sectional perspective view showing one structural unit of a dispensing part. FIG. 11 is a cross-sectional front view of the dispensing component.

  As shown in FIG. 10, in the dispensing component 3, the central axis Acm of the measuring portion 3a and the central axis Acf of the discharge flow path 3b are offset. Similarly to the first embodiment, the dispensing part 3 is set such that the length Lm of the measuring portion 3a is set larger than the diameter Dm (Lm> Dm), and the inner diameter df of the discharge flow path 3b is the same as that of the measuring portion 3a. The inner diameter Dm is set to be smaller (df <Dm), and the length Lm is set to be longer than the length Lf of the discharge flow path 3b (Lm> Lf).

  In the dispensing component 3, even if the central axis Acm of the measuring portion 3a and the central axis Acf of the discharge flow path 3b are offset, the length Lm of the measuring portion 3a is set larger than the diameter Dm (Lm> Dm). ). For this reason, even if the meniscus curvature of the liquid held in the measuring unit 3a is different, the dispensing component 3 can suppress variation in the amount of liquid held in the measuring unit 3a and can always discharge a substantially constant amount of liquid. it can.

  Here, as shown in FIGS. 12 and 13, the dispensing part 3 has a lower part of the measuring part 3 a so that the inner diameter of the lower part of the measuring part 3 a connected to the discharge flow path 3 b gradually decreases toward the discharge flow path 3 b. May be formed into a conical or pyramidal tapered surface 3f. At this time, as shown in FIGS. 14 and 15, the dispensing component 3 may form a stepped portion 3 g at a connection portion between the tapered surface 3 f and the discharge flow path 3 b.

  In addition, the dispensing component of the present invention, like the dispensing component 5 shown in FIG. 16, forms a protruding portion 5c that protrudes in the discharge direction of the liquid at the discharge end of the discharge channel 5b and has an end surface 5d at the tip. The outer surface of the protruding portion 5c may be formed into a tapered surface 5g parallel to the conical or pyramidal tapered surface 5f below the measuring portion 5a.

  Moreover, although the dispensing part of Embodiment 1, 2 demonstrated that the measurement part and the discharge flow path had a circular cross section, the cross-sectional shape may be a polygon other than a circle.

FIG. 3 is a cross-sectional perspective view showing one structural unit of the dispensing component of the first embodiment. It is a cross-sectional front view which shows the meniscus of the dispensing components holding the liquid. It is a cross-sectional front view of the dispensing component shown in FIG. It is a cross-sectional front view which shows the 1st modification of the dispensing components shown in FIG. It is a cross-sectional front view which shows the 2nd modification of the dispensing components shown in FIG. It is a cross-sectional front view which shows the 3rd modification of the dispensing components shown in FIG. It is the cross-sectional front view which showed the 3rd modification of the dispensing components shown in FIG. 1 with the metal mold | die. It is the cross-sectional front view which showed the 4th modification of the dispensing components shown in FIG. 1 with the metal mold | die. It is the cross-sectional front view which showed the 5th modification of the dispensing components shown in FIG. 1 with the metal mold | die. FIG. 5 is a cross-sectional perspective view showing one structural unit of a dispensing component of a second embodiment. It is a cross-sectional front view of the dispensing component shown in FIG. It is a cross-sectional perspective view which shows the 1st modification of the dispensing components shown in FIG. It is a cross-sectional front view of the dispensing component shown in FIG. It is a cross-sectional perspective view which shows the 2nd modification of the dispensing components shown in FIG. It is a cross-sectional front view of the dispensing component shown in FIG. It is a cross-sectional front view which shows the modification of the dispensing components of this invention. It is sectional drawing which shows the shape of the liquid hold | maintained by the conventional dispensing apparatus. It is sectional drawing to which the upper part of the liquid hold | maintained at the dispensing apparatus shown in FIG. 17 was expanded. It is a figure which shows the result of having calculated the relationship between the missing volume of the liquid by a meniscus, and the diameter of opening for every contact angle.

Explanation of symbols

1, 3 Dispensing parts 1a, 3a Metering part 1b, 3b Discharge flow path 1e, 3e Curved surface 1f, 3f Tapered surface 1g Tapered surface 3g Stepped part 5 Dispensing part 5a Metering part 5b Discharge flow path 5c Protruding part 5f Tapered surface 5g Taper surface Ac Center axis Acm Center axis of metering section Acf Center axis of discharge channel df Inner diameter of discharge channel Dm Inner diameter of metering section Lf Length of discharge channel Lm Length of metering section

Claims (3)

A dispensing part that discharges the entire amount of liquid held at once using pressurized gas,
It has an opening formed in the upper part and a space of a certain volume connected to the opening, and uses the volume defined by the gas-liquid interface formed in the opening and the space to create the space. A metering unit for metering and holding the liquid to be filled;
A discharge channel that is connected to the metering unit opposite the opening and that discharges the liquid held in the metering unit when the pressure of the pressurized gas is applied to the liquid;
Comprising
The length of the liquid in the discharge direction in the cross section along the central axis of the measuring unit is so as to suppress variation in the volume of the liquid measured and held by the measuring unit caused by the difference in the gas-liquid interface. Dispensing part characterized in that it is set larger than the length in the direction orthogonal to the discharge direction.   The length of the liquid discharge direction in the cross section in the cross section is set in a range of 2Dm <Lm <10Dm with respect to a length Dm in a direction perpendicular to the discharge direction. Dispensed parts as described in   2. The dispensing part according to claim 1, wherein a length d of the discharge channel in a direction orthogonal to a discharge direction of the liquid is set smaller than a length Dm of the measuring unit.

Images