US 2958517 A
Description (OCR text may contain errors)
Nov. 1, 1950 VESSEL FOR '1 D K. HARKER ET AL ISSUE CULTURE AND THE LIKE COMPRISING A MAGNETIC STIRRER Filed April 28, 1958 INVENTORS DONALD K. HARKER ALLEN R. DE LONG mu-m ATTORNEY 2,958,517 Patented Nov. 1, 1960 VESSEL FOR TISSUE CULTURE AND THE LIKE COMPRISING A MAGNETIC STIRRER Donald K. Harker and Allen R. De Long, Vineland, NJ,
assignors to Bellco Glass, Inc., Vineland, NJ, :1 corporation of New Jersey Filed Apr. 28, 1958, Ser. No. 731,233
2 Claims. (Cl. 259-122) This invention relates to a vessel comprising a magnetic stirrer, and more particularly to a vessel which may be used for tissue culture and for biological and chemical manipulations in which a liquid is agitated at a controlled rate for extended periods of time.
In recent years the development of tissue culture methods for the study of the behavior of single cells and isolated bits of tissues of the multicellular body independent of their usual surroundings has assumed great importance in cancer research, in studies of the physiology of senility, and in the observation of cellular phenomena in living organisms, etc. In many tissue culture techniques, it is necessary to provide the tissue culture medium with continuous controlled agitation for extended time periods. Moreover, it is absolutely essential that the tissue culture medium be maintained sterile and out of communication with sources of contamination.
The use of magnetic stirrers for tissue culture vessels has been suggested. However, for many applications conventional magnetic stirrers which comprise magnetized bars, such as bars having a circular or semicircular crosssection, have proven unsatisfactory. Thus, such magnitized stirring bars are prone to destroy or injure the cells undergoing tissue culture because of the irregular path which such bars assume when undergoing agitation. Moreover, the use of stirring bars raises problems in the handling of the same. Thus, an error in the insertion of the stirring bar into the glass vessel within which it is to be used, such as the dropping of the stirring bar, may result in the breakage of the glass vessel.
This invention has as an object the provision of a vessel comprising a magnetic stirrer.
This invention has as another object the provision of a laboratory vessel comprising a magnetic stirrer in which closely controlled agitation can be obtained.
This invention has as yet another object the provision of a vessel comprising a magnetic stirrer in which random motion of the stirrer during operation is eliminated.
This invention has as a yet further object the provision of a tissue culture vessel in which satisfactory tissue culture may be achieved.
Other objects will appear hereinafter.
For the purpose of illustrating the invention there is shown in the drawings a form which is presently preferred; it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown.
Referring to the drawings wherein like reference characters refer to like parts:
Figure 1 is a perspective view of the vessel comprising a magnetic stirrer of the present invention.
Figure 2 is a vertical sectional view taken on line 22 of Figure 1.
Referring to the drawings, the vessel of the present invention is designated generally as 10. In the illustrated embodiment and in the following description the vessel will be described as a tissue culture vessel wherein minute pieces of tissue which have been separated from a growing mass are placed under aseptic conditions in a nutrient medium and permitted to multiply. However, it is to be understood that the vessel 10 of the present invention may be used for any of a wide variety of purposes in the biological and chemical arts.
The vessel 10 comprises a glass vessel of generally cylindrical configuration having a substantially uniform cross-section throughout its entire height. The mouth of the vessel 10 is provided with an annular ground glass flange member 12a which mates with a similar annular ground glass flange member 12b of the cap 14 of the vessel 19. A gas and liquid tight seal may be obtained between the flange members 12a and 121) by coating the juxtaposed portions thereof with a thin layer of stopcock grease, such as silicone stopcock grease.
The body 16 of vessel lil includes an integral pouring spout 18 which projects angularly upwardly from the wall of the body 16. The pouring spout 18 is secured to the body 16 intermediate the annular ground glass flange member 12a and the floor 20 of body 16. The pouring spout 18 may be provided with any suitable closure member 22. In a tissue culture vessel to be operated under aerobic conditions, the closure member 22 may comprise a cotton plug or a Morton culture tube closure, such as that described in United States Letters Patent No. 2,287,- 746. When the vessel 10' is used in anaerobic studies, then the closure member 22 may comprise a stopper, such as a ground glass stopper or a rubber stopper.
The floor 20 of the vessel 10 is not planar. Instead, the floor 20 is provided with a raised portion 24 which comprises a raised annulus. Within the raised portion 24 there is positioned the depression 26 which comprises a depression on the interior surface of the floor 20, which depression is defined by the raised portion 24 on such interior surface of the floor 20.
The cap 14- of vessel 10 is generally dome-like. The cap 14 is provided with a central integrally-formed dependent tubular member 28 which in the illustrated embodiment projects downwardly from the cap 14 intothe interior of the body 16. The uppermost end of tubular member 28 may be sealed to the atmosphere by closure member 30 which may comprise a rubber stopper or a ground glass closure member.
The stirring member 32 is mounted within the vessel 10 and is guided intermediate the dependent tubular member 28 and the depression 26 in the floor 20 as set forth below.
The stirring member 32 comprises the glass rod 34 which is received within the cylindrical bore of the dependent tubular member 28. The glass rod 34 is loosely fitted within the bore of dependent tubular member 28 in assembled relationship so that binding or frictional engagement between the bore of dependent tubular member 28 and the outside surface of glass rod 34 is minimized. The lowermost end of glass rod 3 4 is provided with the stirrer holder 36.
The stirrer holder 36 is generally in the shape of a top. The upper portion 38 of stirrer holder 36 is substantially cylindrical, while the bottom portion 40 of stirrer holder 36 is pointed,with its pointed end being received within the depression 26 in the floor 20 of the body 16 of vessel 10.
The stirrer holder 36 is preferably formed of a nontoxic plastic or other non-toxic relatively light non-magnetic material. In particular, we have found polymerized tetrafiuoroethylene, such as the plastic Teflon sold by E. I. DuPont de Nemours & Company, Inc., of Wilmington, Delaware, to be an eminently suitable material for forming the stirrer holder 36. Thus, Teflon is nontoxic, relatively light in weight, and self-lubricating. In addition, it possesses superior resistance characteristics to wear, chemical corrosion, retains its properties at elevated temperatures such as boiling liquids, etc.
The upper portion 38 of stirrer holder 36 is provided at its top face with a longitudinal blind bore within which the glass rod 34 is received. The relative dimensioning of the glass rod 34 to the bore within the upper portion 38 of stirrer holder 36 is such that the stirrer holder 36 is frictionally secured to the glass rod 34.
The upper portion 38 of stirrer holder 36 carries the transverse stirrer bar 4-2. The stirrer bar 4-2 is preferably a Teflon-coated bar magnet. Stirrer bar 42 is transversely mounted by being passed through the upper portion 38 of stirrer holder 36 perpendicularly to the longitudinal axis of the stirrer holder 36 with the ends of the stirrer bar 42 being equidistant from the longitudinal axis of the stirrer holder 36.
The vessel of the present invention is supported on the flat-top surface 44 of the housing of a conventional magnetic stirring apparatus 46. No claim is made to the structure of the magnetic stirring apparatus 46, and a wide variety of suitable commercial units of this type may be utilized. For the purposes of illustration, the magnetic stirring apparatus 46 includes the motor 48 which is provided with the upwardly projecting shaft 59 on which there is mounted the bar magnet 52. The ends of the bar magnet 52 are equidistant from the longitudinal axis of the shaft 50. The magnetic stirring apparatus 46 is provided with a heavy base 54 for stability, such base 54 being mounted upon rubber feet 56. The base 54 may also be provided with a two piece swinging arm swiveljoint clamp 58 which permits mounting of the magnetic stirring apparatus on a support stand (not shown). The motor 48 is connected by cord 60 to the rheostat 62, which may be provided with a graduated scale. The rheostat 62 permits selective control of the speed of rotation of the motor 48.
The operation of the vessel 10 of the present invention is as follows: upon rotation of the bar magnet 52 through the turning of the shaft 50 by the motor 48, the stirrer holder 36 will be rotated since the bar magnet 52 will magnetically affect the magnetized stirrer bar 42. The speed of rotation of the stirrer holder 36 may be closely controlled by the rheostat 62.
The rotation of the stirrer bar 42 and its stirrer holder 36 is such that the same is always in a fixed plane. Scraping of the stirrer bar 42 on the interior wall surface of the vessel 10' is entirely eliminated. The point contact between the bottommost tip of bottom portion 40 of stirrer holder 36 and the depression 26 of the floor of the body 16 is at a low frictional level so that the same constitutes a low friction bearing enabling the stirring member 32 to be rotated at high efiiciency.
The cylindrical interior of the body 16 and the positioning of the stirrer bar 42 generally midway between the point of entry of the pouring spout 18 into the wall of the body 16 and the floor 20 of the body 16 permits substantially uniform agitation to be achieved throughout the liquid medium 64 disposed within the body 16.
The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and, accordingly, reference should be made to the appended claims rather than to the foregoing specification as indicating the scope of the invention.
1. A vessel for tissue culture and the like comprising a non-magnetic hollow, imperforate body, a hollow imperforate cap surmounting said body with the free edge portion of said cap being operatively disposed in gastight sealing relationship to the topmost edge of said body, bottom guide means in the central portion of the floor of said body, a tubular top guide depending from said cap, said tubular guide being juxtaposed to, axially aligned with, and spaced from said bottom guide means in the central portion of the floor of said body, removable means for sealing the uppermost portion of said tubular top guide, a non-magnetic elongated stirring member rotatably guided by said tubular top guide, the topmost end of said stirring member being operatively engaged with said tubular top guide and spaced from the uppermost end thereof, the bottommost end of said stirring member having guide means which operatively mate with the bottom guide means in the central portion of the floor of said body, and a magnetized stirrer element carried by said stirring member at a spaced distance above the bottom guide means in the central portion of the floor of said body.
2. A vessel in accordance with claim 1 which includes a pouring spout in the wall of the vessel intermediate said cap and the floor of the vessel.
References Cited in the file of this patent UNITED STATES PATENTS Baron June 3, 1958