TECHNICAL FIELD The present invention is generally related to methods and apparatus for comminuting biological specimens onsite or in a laboratory, and is more particularly related to devices used for providing biological specimens for subsequent chemical analysis.

BACKGROUND ART Increased drug abuse in North America has been associated with criminal activities, health problems, newborn addiction, lost worker productivity and staggeringly high medical costs. Currently of greatest concern are opiates (heroin, morphine, codeine), cocaine, marijuana, MDMA (Ecstasy), phencyclidine, amphetamine and methamphetamine. Possible pesticide residues in the breast tissues of women and the concern over the presence of synthetic agents and compounds in plant and animal foodstuffs has raised concerns about possible environmental exposure including air- and water-borne agents, as well as, exposure of domestic animals to agricultural chemical agents such as pesticides and herbicides, growth hormones and/or antibiotics. Verifying a natural "organic" status prior to slaughter has, thus, recently become of significant interest. In testing for human drugs of abuse, several test systems are presently marketed for detecting drug analytes in urine e.g., ONTRAK™ and ONLINE™ (Roche Diagnostic Systems, Inc.), the ADx™ automated fluorescence polarization immunoassay system (Abbott Laboratories, Inc.) and EZ-SCREEN™ (Environmental Diagnostics). Unfortunately, there are significant problems associated with urine testing for drugs of abuse, e.g., (i) possible false positive results for opiates recorded in subjects who are on certain medications and who have recently ingested poppy seeds; (ii) rapid elimination rates and short half- life of many drug metabolite compounds; and particularly (iii) false negatives associated with purposeful adulteration and interference. Unlike liquid urine samples, solid samples such as hair require special sample preparation prior to conducting assays. Conceptually, hair provides a better toxicological specimen than urine, serum, sweat or saliva because its relatively slow growth may increase the period of time during which drug usage is detectable. Human hair grows approximately 1/64 (0.016) inch per day. It takes about one week after ingestion of drugs for the drugs to be extractable from hair outside the scalp. In present day practice, extraction of drugs from hair often involves exposure to acid and/or base hydrolysis, prolonged enzymatic digestion, heat, organic solvent extraction and/or sonication. These labor-intensive methods require technical experience and are presently most easily conducted in a test laboratory. However, even then the sample process can take two to three hours to complete, and he results are not available for as long as seven days, the samples frequently suffer from poor reproducibility, there are long delays before results can be released and, even then, variability in the ability to isolate different drugs and their metabolites. Hydrolysis conditions can also result in conversion of drug metabolites such as 6-monoacetylmorphine, i.e., whose presence provides judicial proof of drug abuse, into parent compounds, i.e., morphine. Fortunately, it has been found that certain drugs and their metabolites can persist in hair for extended periods of time. Currently, to prepare a sample of hair for chemical analysis, technicians freeze dry the sample using liquid Nitrogen, then cut it into small pieces using razor blades or scissors. The comminution or maceration operation is useful for increasing the reaction time of the analytical chemicals on the sample. This procedure is labor intensive, time consuming and is subjective as to the particular cutting techniques of individual technicians. Also, when a high volume of specimens needs to be analyzed, technicians are subject to repetitive stress injuries. In some cases, the amount of specimens obtained for analysis may vary by sample as well as by individual technician. An alternative procedure for comminution involves a ball mill, but that device inherently has contamination issues with the balls from sample to sample. Once the hair is cut up, it is placed in a test tube where a conventional chemical is applied. There is a need for a comminution method and apparatus for biological specimens such as hair which is easily adapted to mass production collection and testing techniques. There is also a need for a comminution method and apparatus for such specimens which is repeatable on an objective basis.

DISCLOSURE OF INVENTION The above-identified needs are met or exceeded by the present method and apparatus for the comminution of biological specimens, which provides a receiving unit and a disposable sample retainer. The preferred receiving unit is provided with a drive system for powering the comminution of the specimen and for temporarily accommodating a sample retainer. In the preferred embodiment, the sample retainer includes comminution elements which reduce the specimen to a granular or powder-like state for more efficient use of chemicals. Further, the receiving unit is preferably configured for enhancing the collection of ground specimen from the sample retainer. The present apparatus is used to collect a sample of hair, feathers, nails, hooves or the like from a specimen and allows for the accurate and rapid collection of the sample. In a preferred embodiment, the apparatus collects from about 10-20 hairs of about 1.5 inches in length, representing about 90 days of potential drug use. More specifically, an apparatus for comminuting biological specimens includes a receiving component provided with a drive source, a sample retainer configured for retaining at least one biological specimen and for engagement in the receiving component, and a single use comminution mechanism in operational relationship with the sample retainer. The drive source is configured for driving the comminution mechanism. A collector is associated with the receiving component for receiving comminuted product generated by the comminution mechanism. In another embodiment, a disposable sample retainer is provided for use with a comminution apparatus for comminuting a biological specimen, and includes a first portion configured for retaining the specimen and having a first comminution surface, a second portion configured for operational engagement with the first portion and having a second comminution surface, the first and second comminution surfaces being rotatable relative to each other for comminuting the specimen held therebetween.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top perspective view of the present comminution apparatus; FIG. 2 is a side view of the apparatus of FIG. 1 with portions omitted for clarity; , FIG. 3 is an exploded perspective view of the sample retainer apparatus of FIG. 1; and FIG. 4 is a vertical section of an assembled view of the sample retaining apparatus of FIG 3.

BEST MODE OF CARRYING OUT THE INVENTION Referring now to FIG. 1, an apparatus for comminuting biological specimens or samples is generally designated 10 and is intended for comminuting specimens or samples such as hair, nails, fur, feathers, hooves or other materials having keratin or which are known or believed to contain compounds accessible through chemical analysis. While the present apparatus 10 is depicted in a configuration for processing one specimen at a time, it is contemplated that the present principles of operation are convertible into an embodiment comminuting multiple specimens at a time. More specifically, the apparatus 10 includes a base unit or receiving component, generally designated 12 having a housing 14 constructed and arranged for supporting various operational components described below. In the preferred embodiment, the housing 14 is configured for placement upon a table or other work surface, and the use of terms such as "top", "bottom", "upper" and "lower" refer to the apparatus 10 as depicted in FIG. 1, however other orientations are contemplated depending on the application. The apparatus 12 is provided with a drive source 16 preferably taking the form of an electric motor (best seen in FIG. 2), powered by either line voltage or battery power, which is located within the housing 14 so that a drive gear 18 driven by the motor is accessible. In the preferred embodiment, the drive gear 18 is disposed on a top surface 20 of the housing 14 in operational proximity to a sample well 22. The generally cylindrical sample well 22 is defined by a chamber 24 depending from the top surface 20 and being in fluid communication with an interior cavity 26, preferably through an open bottom 28. At a lower end 30 of the chamber 24, a pair of opposing "L"- brackets 32 are disposed in generally parallel, spaced relationship to each other. The brackets 32 are configured for slidingly receiving a generally funnel- shaped filter collar 34 provided with at least one laterally extending flange 36 for slidingly engaging the brackets 32. An upper end 38 of the filter collar 34 has a flange 39 (FIG. 2) for engaging the brackets 32 and is generally greater diameter than a lower end 40, which is configured for passing comminuted sample from the chamber 26 into a receiving collector 42. In the preferred embodiment, the collector 42 is at least one conventional test tube provided in a size suitable for such specimen analysis as is well known in the art. Among others, suitable test tube sizes include 10X40mm, 13X45mm, 13X50mm and 13X60mm. Alternatively, the known "Hitachi" cups are contemplated. The housing 14 of the receiving component 12 is preferably configured for retaining the collector 42 in a collecting position (best seen in FIG. 1). While a variety of clamping formations, clips or brackets are contemplated, the preferred structure is a clip 44 having a generally "U"-shape when viewed in lateral section, having a pair of generally parallel spaced vertically extending arms 46. It will be appreciated that the spacing of the arms 46 is determined by the size of the desired test tube 42, and it is contemplated that the clip 44 as well as an underlying panel 48 may be exchanged for other sizes when other test tube sizes are to be used with the apparatus 10. Thus, the spacing of the arms 46 will be sufficient to provide a slight yet positive gripping force on the test tube 42 without causing damage. It is also contemplated that the lower end 40 of the filter collar 34 will fit inside an upper end 50 of the test tube 42. Referring now to FIGs. 3 and 4, an important portion of the comminution apparatus 10 is a sample retainer, generally designated 52, configured both for retaining at least one biological specimen and for engagement in the sample well 22 of the receiving component 12. The sample retainer 52 is operationally associated with a single use comminution mechanism configured for converting a raw specimen into a granular or powdery product more amenable to chemical analysis. In the preferred embodiment, this comminution is obtained by relative rotation of a first component of the sample retainer relative to a second component. This relative rotation is powered by the driving source 16. The comminuted sample is received in the filter collar 34 and ultimately in the collector or test tube 42. It is contemplated that the receiving component 12 may alternately have a separate single use comminution mechanism separate from the sample retainer. More specifically, in the embodiment of FIGs. 3 and 4 the sample retainer 52, also referred in some cases as "a consumable" since it is designed for single use, includes a first component referred to as a cup 54 configured for retaining the sample or specimen 56, here depicted as a group of hair fibers cut to an approximate 1.5 inch length and having a weight of approximately 20 mg. The dimensions of the sample retainer 52 are chosen based on the desired sample size.

However, it is contemplated that the size of the sample 56 may vary with the application and/or with the type of hair collected. The cup 54 is generally cylindrical in shape, with an open upper end 58 defined by a generally tubular sidewall 60. While other lengths are contemplated, the present sidewall is at least approximately 1.5 inches in length and about 0.875 inch in diameter to adequately accommodate the sample 56. Opposite the upper end 58 is a lower end 62 provided with a supportive grid 64. The grid 64 consists of first and second pluralities of spaced bars oriented normally to each other. As a result, a supportive yet porous surface is obtained. The grid 64 is secured to the lower end 62 either by being integrally molded to the sidewall 60 or held there by chemical adhesive, ultrasonic welding or similar fastening techniques. Atop the grid 64 is secured at least one first comminution surface 66 provided in the form of a generally planar perforated metal disk. In the preferred embodiment, the disk 66 is made from electric shaver foil having apertures in the approximate range of 0.025inch, however the size of the openings in the disk may vary to suit the application, provided they are large enough to pass comminuted hair fibers therethrough. Hair fibers typically have a diameter in the range of 0.002-0.004 inch. Another desirable property of the disk 66 is that it is designed to serve as a fixed surface or "anvil" and as such is perforated but has a generally level upper surface. In the preferred embodiment, this surface is produced by electroplating or electrodeposition. The disk 66 is preferably secured to the grid 64 by chemical adhesive, ultrasonic welding, insert molding or similar fastening technology. While a shaver foil is the preferred material for the comminution surface 66, it is contemplated that other materials would be suitable provided they produce comminuted hair suitable for chemical analysis. It is also contemplated that the comminution surface 66 may be integrally formed with the grid 64 and even be made of the same material. A second component of the sample retainer 52 is referred to as a ram 68 and is configured for operational engagement with the cup 54 and having at least one second comminution surface 70. The ram 68 pushes the sample 56 toward the first comminution surface 66 and maintains the sample there until comminution is complete. Another function of the ram 68 is to provide the second comminution surface 70, which acts against the first surface 66 to comminute the sample 56. Since the comminution process is obtained through relative rotation of the first and second surfaces 66, 70 in the preferred embodiment the ram 68 is configured for being rotated by the motor 16, and as such functionally serves as the "hammer" of the two comminution surfaces 66, 70. The disk 70 secured to the ram 68 is preferably made by stamping, and as such each perforation is bounded by displaced metal, forming relatively sharp edges. The sharpness of the edges may be enhanced by subsequent grinding operations. While shaver foil is the preferred material for the surface 70 other suitable surfaces or materials are contemplated which provide sufficient abrasive force when rotated against each other to comminute strands of hair into a granular or powdery consistency. Also, while the comminution apparatus is presently disclosed in the form of opposed comminution surfaces 66, 70, other comminution apparatus capable of comminuting such biological samples are contemplated. It is further contemplated that the foil surfaces 66, 70 may be exchanged on the respective cup 54 and ram 68 and also that the cup may rotate relative to the ram. Since the ram 68 is movable relative to the cup 54, it is provided with a gear 72 or equivalent drive formation opposite the comminution surface 70. In the preferred embodiment, the gear 72 is integrally molded to the ram 68 and is provided with a radially extending tooth configuration which meshes with the drive gear 18. The precise tooth pattern may vary to suit the application as is known in the art. Another feature of the ram is that it is preferably configured for retaining the sample 56 between the surfaces 66, 70. To that end, the ram 68 is provided with a sample retainer formation 74 for retaining the sample in place during comminution. It has been found that sample portions often creep upward away from the surfaces 66, 70. The present sample retainer formation 74 is preferably formed as a radially extending helical rib which prevents the sample 56 from migrating away from the surfaces 66, 70 by forming a downward directing, moving barrier which acts against an inner surface of the cup 54 and rotates with the ram 68. Through the use of the retainer formation 74, the sample is maintained in operational relationship to the comminution surfaces 66, 70. An important feature of the present sample retainer 52 is that it is disposable to facilitate single use and avoid cross contamination of samples. Accordingly, the cup 54 and the ram 68 are configured for easy detachability from the sample well 22. In the preferred embodiment, the sample retainer 52 is vertically removable from the well, however other disengagement configurations are contemplated. With the preferred configuration, when the sample retainer 52 is removed, the comminution surfaces 66, 70 as well as the drive formation 72 and the retainer formation 74 are also removed, those being the surfaces subject to contact with the sample 56, before and after comminution. In addition, the cup 54 and the ram 68 are made of relatively inexpensive materials. Referring now to FIG. 2, once the sample 56 is placed between the surfaces 66, 70 and there is resulting relative rotation by the drive source 16 for a specified period of time, the comminuted sample passes through the apertures in the surface 66, through the supportive grid 64 and into the filter collar 34. It has been found that in some situations, the comminuted sample does not fall freely into the filter collar 34 and ultimately into the collector 42. As such, the receiving component 12 is preferably provided with at least one flow enhancer 76. In the preferred embodiment, one flow enhancer 76 is a vacuum fan (FIG. 2) which creates a negative pressure at the filter collar 34 by drawing air flow through an elbow duct 78 located within the receiving component 12 and which is in fluid communication with the filter collar. Air flows through the filter collar 34 in a generally lateral direction by virtue of a porous filter screen 80 (FIG. 2) affixed in an opening in a wall of the filter collar. A mesh size is selected for the filter screen 80 so that air flows through, but comminuted bits of sample 56 are caught on the screen. In instances where there is a need for enhanced retention of the volume of comminuted sample, a motor 84 powering the vacuum fan 76 may be intermittently energized, instead of being constantly energized. It is believed that intermittent energization will enhance retention of comminuted sample 56. The filter collar 34 is mounted in the receiving component 12 so that the filter screen 80 is in communication with the duct 78. To provide adequate suction generated by the fan 76, the duct 78 has a collar end 82 (shown partially cut away) configured for tightly engaging the conical wall of the filter collar 34. It is also contemplated that a second flow enhancer is provided, designated 86. In the preferred embodiment, the second flow enhancer 86 is a vibrator, which generates pulse impacts against the filter collar 34 to facilitate the downward flow of comminuted sample 56 into the collector 42. More specifically, the vibrator 86 in one embodiment includes a motor 88 powering an eccentric cam 90 which is in periodic contact with the filter collar 34. Other configurations and orientations of vibrating mechanisms are contemplated, provided the flow of comminuted sample is enhanced. Referring now to FIGs. 1 and 2, for beneficial results, it is preferable that there be a biasing force exerted against the sample retainer 52 so that the respective comminution surfaces 66, 70 exert sufficient pressure against the sample 56 to achieve desirable comminution. Accordingly, the receiving component 12 is provided with least one biasing device 92 configured for exerting a biasing force on the sample retainer 52. The preferred biasing device 92 is a releasable clamp affixed at a base 94 to the top surface 20 of the receiving component 12. An over center lever/cam apparatus 96 is secured to the base 94 and includes a handle 98 and an actuator arm 100. At a free end of the actuator arm 100, a contact pad 102 is secured and is biased vertically by a spring 104. The amount of spring force exerted by the contact pad 102 is determined by a threaded adjustment of an attachment rod 106. When the handle 98 is pressed in a downward position (FIG. 1), the actuator arm 100 is fixed in a lowered position with the contact pad 102 impacting an end 108 of the ram 68 having the gear 72. Thus, the contact pad 102 exerts a vertical biasing force against the ram 68, forcing the surface 70 against the comminution surface 66 in the cup 54. It has been found that about 41psi of force provides suitable results, but other degrees of biasing force are contemplated depending on the application. In the biased position shown in FIG. 1, the gear 72 is meshed with the drive gear 18. It is contemplated that the contact pad 102 rotates with the ram 68 when the drive gear is driving the ram to effect comminution. Upon completion of the comminution process, the handle 98 is pulled upward to release the biasing force on the ram. At that point, the sample retainer 52 may be withdrawn from the receiving component 12. As the ram 68 rotates relative to the cup 54, the cup is held stationary or prevented from rotation by being keyed to the sample well 22. At least one radially projecting lug 110 on the cup 54 is received in a corresponding slot 112 in the sample well 22. Upon vertical insertion of the sample retainer 52 into the sample well 22, the lug 110 is engaged in the slot 112 to properly seat the sample retainer. Control over the comminution operation is maintained by a control circuit 114 represented by a start switch located on the receiying component 12. As is well known in the art, the switch 114 is configured for controlling the operation of the drive motor 16 as well as the vacuum fan motor 84 and the vibrator motor 88 if included. Also, while only one sample retainer 52 and associated receiving portion 12 are discussed, it is contemplated that a unit incorporating the above-described principles of operation may be provided with the capability of simultaneously processing at least as many as eight samples at a time. In such situations it is contemplated that the functions of driving the gear 72 on the ram, exerting the biasing force to facilitate comminution and initiating the vacuum may be performed by a master control circuit 114 operating on multiples of the components described above. Also, it is contemplated that a microprocessor (not shown) may be provided to the control circuit 114 for varying the time of comminution, vacuum and/or vibration as a function of the size of the sample. It is also contemplated that replacement kits of consumables be provided to users of the receiving component 12 or similar device. Such a kit would include at least a cup 54 with the grid 64 and the first comminution surface 66, a ram 68 with the second comminution surface 70. In addition, the kit would preferably include a filter collar 34 and a collector or test tube 42. Thus, any of the components coming in contact with the specimen are single use and disposable. In operation, the present invention also contemplates the following method of comminuting specimens or samples for obtaining subject matter upon which chemical analysis may be performed. While the method is preferably performed with the apparatus described above, it is contemplated that other apparatus may be provided for achieving the same goals of generating comminuted sample material suitable for chemical testing. More specifically, the method includes first providing a biological sample comminution device including the receiving component 12 provided with the drive source 16, the sample retainer 52 configured for retaining at least one biological specimen 56 and for engagement in the receiving component 12, the sample retainer associated with .a single use comminution mechanism 66, 70, the drive source configured for driving the comminution mechanism and a collector 42 associated with the receiving component for receiving comminuted product generated by the comminution mechanism. Next, the filter collar 34 is loaded into the receiving component 12, after which the collector 42 is also loaded onto the component. As an option, the biological sample 56 is prewashed with ethanol or other suitable volatile solvent to remove external substances from the specimen which may skew the results of the analysis. The biological sample 56 is then placed into the first component 54 of the sample retainer 52, and the first component is then loaded into the receiving device. It has been found that the samples of hair are awkward to handle and are difficult to position suitably at the bottom of the cup 54. It has been found that if the hair is moistened with ethanol it is easier to locate in the cup. Also, the ethanol quickly vaporizes without residue, especially when vacuum is used. Alternately, tweezers, cardboard or otherwise disposable plungers, or a technician's finger may be used for placing the sample. The source of vacuum is then turned on for drawing air through the sample retainer to dry the sample. After the sample is dry, the second component 68 of the sample retainer 52 is engaged with the first component of the sample retainer with the biological sample 56 therebetween. A biasing force is exerted against the first component of the sample retainer so that a first comminution surface on the first component engages a second comminution surface on the second component, and the drive source is initiated to rotate the sample retainer to cause comminution of the specimen within the retainer. If desired, vacuum and/or vibration are employed to facilitate movement of comminuted sample into the collector 42. It will be seen that the present sample comminution apparatus more efficiently provides comminuted sample for subsequent chemical analysis. It has been found that a typical 20mg sample of hair requires only 2 minutes of comminution to reach a sufficiently comminuted consistency for chemical analysis. Using the present system, the process of comminution and chemical extraction has been reduced from several hours to about 30 minutes, and can be performed onsite rather than in a remote laboratory. Samples produced according to the present invention have been found to provide 25- 40% more accurate readings in the subsequent chemical analysis than samples prepared according to prior techniques. The present system for comminuting hair samples has been found to expose the hair's cortex to enhance the reactivity of the hair with the analytical chemicals. While specific embodiments of the present method and apparatus for the comminution of biological specimens has been shown and described, it will be appreciated by those skilled in the art that changes and modifications may be made thereto without departing from the invention in its broader aspects and as set forth in the following claims.