Analytic device utilizing a reaction-sensitive chemical product
United States Patent [1 1 Montagnon Apr. 8, 1975 [75] Inventor: Paul A. F. Monta gnon, La  
 Balme-les-Grotte (Isere), France [73] Assignee: Analytab Products Inc Carle Place,  
 [22] Filed: Apr. 27, 1973 [21] Appl. No.: 355,087  
 [30] Foreign Application Priority Data May 18, 1972 France 72.18386 [56] References Cited UNITED STATES PATENTS Johnson et al..... 23/253 X Hamilton 23/259 X Mirasol, Jr 23/259 X 3,689,224 9/1972 Agnew et a1. 23/253 TP 3.740.196 6/1973 Stroterhoff 23/253 TP 3,768,974 10/1973 Storm 23/259 X Primary E.\aminerR. E. Serwin Attorney, Agent, or Firm-Kenyon &amp; Kenyon Reilly Carr &amp; Chapin 57 ABSTRACT An analytic device of the type utilizing a chemical product, such as an indicating reagent which undergoes a color change, sensitive to a condition being analyzed. The device includes a generally tubular, upright vessel open at its upper end and having a closed lower end. A flange extending around the interior of the vessel closely above its lower end defines a groove about the lower interior region of the vessel. An annular disc of absorbent material impregnated with the chemical product rests against the lower end of the vessel with its outer peripheral edge snugly received within the groove so that the disc is prevented from displacement. A central opening may be provided within the disc to permit trapped air to escape when test liquid is added to the vessel.  
 10 Claims, 4 Drawing Figures FiG.2  
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  ANALYTIC DEVICE UTILIZING A REACTION-SENSITIVE CHEMICAL PRODUCT BACKGROUND OF THE INVENTION This invention relates to an analytic device of the type comprising a vessel in which is mounted a piece of absorbent material impregnated with an indicating reagent which undergoes a change, typically in color, when acted upon by a sample of liquid under analysis having a particular property to which the reagent is sensitive.  
  In performing&#39;chemical or biological analyses, one common form of test employs analysis materials comprising absorbent material (typically paper) impregnated with chemical products sensitive to the chemical or biological analysis being performed. Such products, for example, include reagents which change color dependent upon acidity or alkalinity, or upon the presence or absence of a particular chemical or biological substance to which they are sensitive. The user may be supplied with the impregnated material in disc or band form and with a tube in which the impregnated material is to be mounted, after which the liquid to be tested is introduced to the tube and applied to the material.  
  Such an arrangement, however, can present certain difficulties. The initial introduction of the disc into the tube can be a troublesome manipulation, particularly where a small diameter tube is involved. Thereafter the introduction of the test liquid into the tube can present further problems because the disc may become dis placed due to flotation in the liquid introduced. In addition air bubbles may become trapped beneath the disc so that it is not fully exposed to the liquid being tested.  
 SUMMARY OF THE INVENTION The present invention provides an analytic device utilizing a reaction-sensitive chemical product, intended to obviate or minimize problems of the type previously discussed.  
  In particular an analytic device constructed in accordance with the present invention includes a generally tubular upright vessel open at its upper end and having a closed lower end. An internal flange defines a groove extending peripherally about the interior of the vessel adjacent its lower end. A disc of absorbent material impregnated with the sensitive chemical product rests against the lower end of the vessel with its outer peripheral edge snugly received within the groove. By this construction upward floating of the disc upon the introduction of liquid into the test vessel is prevented. In a further aspect of the invention, a central opening may be provided in the disc so that bubbles of air, which may be created when the test liquid is introduced, can float freely to the surface without being trapped beneath the disc.  
 BRIEF DESCRIPTION OF THE DRAWINGS An analytic device constructed in accordance with one preferred embodiment of the invention and certain additional embodiments is illustrated in the accompanying drawings in which;  
  FIG. 1 is a cross sectional, side view of an analytic device constructed in accordance with the preferred embodiment of the invention; and  
  FIGS. 2-4 are cross sectional side views showing three alternative embodiments of the construction of the analytic device.  
 DETAILED DESCRIPTION Referring to FIG. 1 of the drawings, an analytic device constructed in accordance with the preferred embodiment of the invention is there shown.  
  The device comprises an upright vessel 10 having an open upper end, a vertical tubular sidewall and a closed, flat horizontal lower end 11. An annular flange 12 fixedly secured to the vertical tubular sidewall of the vessel 10 extends peripherally around the interior thereof spaced closely above the lower end 11. The flange 12 and the lower end 11 together define a peripherally extending groove adjacent the lower end of the vessel and this groove snugly receives the outer peripheral edge of a flat horizontal disc 13. The disc 13 is made of absorbent material, such as paper, impregnated with a chemical product suitable for the contemplated analysis. The chemical product may for example be a reagent for metering the glucose in urine, or measuring an attack on protein by an enzyme. Other chemical products may be used for metering purposes such as metering of seric phosphatases, of seric transaminases or of lacticodeshydrogenases. Further chemical products may be used for the study of a lecithinase, of a caseinolyse, of a collagenose or of a coagulose. However, the invention is not to be limited to such reagents but includes any chemical product to be used for the analysis intended to be performed.  
  The disc 13 extends from closely adjacent the vertical sidewall of the vessel 10 inwardly of the flange 12 so that portions projecting inwardly of the flange are exposed to view. As the material to be tested is introduced in liquid form, the disc 13 will undergo a color or other change if the test material meets the required condition for activation of the chemical product with which the disc is impregnated and the change will be visible to the user. The flange 12 may be made of transparent material so that the color change of the disc may be more readily observed.  
  Because of the generally cup shaped configuration of the vessel, test liquid may readily be introduced without difficulty. In particular the mounting of the disc with its peripheral edge anchored within a groove, defined by the flange l2 and the lower end 11, ensures that the disc will not tend to be displaced upwardly within the vessel by flotation but will be retained in position.  
  In a further aspect of the invention, the disc 13 may be provided with a central opening which permits the free escape of air from beneath the disc so that air bubbles do not tend to become entrapped underneath it.  
  Various forms of construction may be utilized to mount the flange within the disc. In the second embodiment shown in FIG. 2 the vessel 20 is made in two parts, a dish shaped lower end 5 containing an upwardly facing horizontal rim about its periphery and an open-ended upper tube containing a corresponding horizontal rim about its lower periphery. The flange comprises a plate 24 having a central opening with the outer portions of the plate being mounted between the rims of the upper and lower parts of the vessel which are fixedly connected together along an annular seam 6 by any conventional bonding or adhesive process. The disc 13 is mounted between the underside of the flange and the lower end.  
  A third embodiment shown in FIG. 3 is generally similar to the second embodiment shown in FIG. 2 but with the difference that the lower end is flat and that the plate 14 configured as an inverted dish to provide a recessed space within the disc 13 is received.  
  In a fourth embodiment shown in FIG. 4 the vessel 40 is of upwardly and outwardly flared configuration and nestingly receives a correspondingly configured inner cup 7. The disc 13 is mounted between the lower ends of the cup and the vessel and extends radially inwardly of a central opening through the lower end of the inner cup. At their upper ends the vessel 40 and the inner cup 7 are provided with overlapping horizontal flanges connected together along a seam line 8.  
  With any of the above forms of construction, a number of the analysis devices may be connected together in rows. In addition the vessels may be of the generally round cross section as disclosed or may, alternatively, be of elongate, irregular, or any other desired cross section.  
 What is claimed is:  
  1. An analysis vessel for holding fast therein a member impregnated with a reagent for analyzing a substance in a liquid to be placed in said vessel comprising:  
 a. a tubular enclosure having side walls, an open top and a bottom;  
 b. means within said enclosure, protruding inwardly from said side walls and in spaced parallel relation above said bottom, for defining a groove adjacent said bottom extending about at least a portion of the periphery of said enclosure, said groove facing and communicating with the remainder of the interior of said enclosure,  
 whereby the impregnated member may be at least par tially engaged in said groove and thereby anchored within said enclosure.  
 2. The vessel of claim 1, further comprising:  
 a. said tubular enclosure having a substantially circular cross-section b. said groove being of annular configuration and extending about the entire periphery of said enclosure for receiving and engaging therein the outer periphery of a disc-shaped impregnated member.  
 3. The analysis vessel of claim 1 further comprising:  
 a. said bottom of said enclosure being a member distinct from said side walls, said bottom member being dished downwardly over its central portion, defining a relieved portion therein, and  
 b. said means for defining a groove comprising a substantially flat flange member sandwiched between said side walls and said bottom member, said flange member having an aperture in its central region over a portion of said relieved portion of said bottom member forming a flange extending inwardly from about the periphery of said side walls over a portion of said bottom member.  
 4. The analysis vessel of claim 1 further comprising:  
 a. said bottom of said enclosure being a substantially flat member distinct from said side walls, and  
 b. said means for defining said groove comprising a flange member sandwiched between said side walls and said bottom member, said flange member being relieved upwardly over its central portion defining with said bottom member a groove about the bottom interior of said enclosure, said flange member also having an aperture in its central region.  
 5. The analysis vessel of claim 1, further comprising:  
 said means for defining a groove comprising a liner having a configuration substantially corresponding to that of said enclosure and being nestable within said enclosure in a position allowing spacing between the bottoms of said enclosure and said liner, said liner additionally having an aperture in its bottom, whereby the impregnated member can be held in the space between said bottoms of said enclosure and said liner, said aperture permitting communication between said impregnated member and the interior of said liner.  
  6. An analytic device utilizing a chemical product for analyzing a substance in a liquid to be placed in said device, the device comprising:  
 a. a generally tubular vessel having side walls and a bottom;  
 b. means within said vessel and protruding inwardly from said side walls for defining a groove extending about at least a portion of the periphery of said vessel adjacent said bottom thereof; and  
 c. a disc of absorbent material impregnated with the chemical product, said disc being disposed within the vessel and resting against said bottom of said vessel with an outer peripheral edge of said disc snugly received within said groove thereby anchoring said disc against displacement relative to said vessel.  
  7. An analytic device as defined in claim 6 wherein said disc further includes a central opening extending through said disc.  
  8. An analytic device according to claim 6 wherein the means defining the groove being a flange forming an opening adjacent the center portion of the vessel and the disc of absorbent material having an aperture therein underlying the opening of the flange and providing a cavity within which the liquid with the substance to be analyzed can be viewed.  
  9. An analysis vessel for holding fast therein a portion of material including a reagent for analyzing a substance in a liquid to be placed in said vessel comprising:  
 a. a tubular enclosure having side walls, an open top and a bottom;  
 b. means within said enclosure protruding inwardly from said side walls and in spaced parallel relation above said bottom, for defining a groove adjacent said bottom extending about at least a portion of the periphery of said enclosure, said groove facing and communicating with the remainder of the interior of said enclosure,  
 whereby the portion of material may be at least partially engaged in said groove and thereby anchored within said enclosure.  
  10. An analytic device utilizing a chemical product for analyzing a substance in a liquid to be placed in said device, the device comprising: 7  
 a. a generally tubular vessel open at its upper end and having slide walls and a bottom;  
 b. means within said vessel and protruding inwardly from said side walls for defining a groove extending about at least a portion of the periphery of said vessel adjacent said bottom thereof; and  
 c. a disc of material including the chemical product,  
 said disc being disposed within the vessel and resting against said bottom of said vessel with an outer peripheral edge of said disc snugly received within said groove thereby anchoring said disc against displacement relative to said vessel.  
 * l l i= UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,876,378 Dated April 1 7 lnventofls) Paul A.F. Montagnon It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:  
 Colunm 3, line 3, after &#34;space within&#34; insert ---which-.  
 Signed and sealed this 1st day of July 1975.  
  l3 EAL) Attest:  
  C. FLARE-FALL DANN RUTH C. l-EASON Commissioner of Patents Attesting; Officer and Trademarks