A pre-injection sample sequencing subsystem for laboratory apparatus which includes a chromatograph with a column includes a circular tray with a plurality of concentric arrays of physical locations for storing sample vials in radially extending linear arrays, and a plurality of virtual locations that are extensions of the linear arrays. Each of the physical and virtual locations are individually addressable by a controller for a robot on the tray such that pre-injection sample processing modules may be attached to the tray, located at one or more of the virtual locations. A sequencing method optimizes transfer of samples contained in the vials between their respective physical storage location and the pre-injection processing modules.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates generally to the field of analytical instrumentation 
and methods which are useful in chemistry (e.g., spectroscopy and 
chromatography), and more particularly to laboratory systems as well as 
subsystems and methods for use with such laboratory systems, including 
methods for sequencing a plurality of samples through gas or liquid 
chromatographs, mass spectrometers and the like. 
2. Statement of the Prior Art 
In the field of chromatography, there are several known systems, subsystems 
and methods which have been utilized to optimize laboratory analysis of 
samples with a gas or liquid chromatograph, "PyTechnology.TM." systems, 
manufactured by Zymark Corporation of Hopkinton, Mass., are illustrative 
of such systems, subsystems and methods. 
As is known, "PyTechnology.TM." systems incorporate a core system which 
includes a Zymate II laboratory robot (and controller) that is attached to 
a central locating plate, around which all other "PySections" are located. 
The central locating plate is divided into forty-eight sectors, and the 
hardware for each "PySection" (e.g., a dispenser or a centrifuge) is 
mounted on a wedge-shaped platform which occupies one or more of the 
forty-eight sectors. 
Illustrative references which describe the robot used in "PyTechnology.TM." 
systems are: U.S. Pat. No. 4,488,241; U.S. Pat. No. 4,507,044; and U.S. 
Pat. No. 4,510,684; each of which was invented by Hutchins et al., is 
assigned to Zymark Corporation, and is incorporated herein by reference. 
A user of such "PyTechnology.TM." systems "teaches" or programs the 
controller of the desired position for each "PySection", and such 
positions are automatically stored in the controller as additional 
"PySections" are added. Once a "PySection" has been put into place, the 
robot is able to automatically access all working positions on that 
"PySection" without any additional teaching or programming by the user. 
Illustrative references which describe the robot controller used in 
"PyTechnology.TM." systems are: U.S. Pat. No. 4,578,764; U.S. Pat. No. 
4,586,151; U.S. Pat. No. 4,689,755; and, U.S. Pat. No. 4,727,494; each of 
which (with the exception of U.S. Pat. No. 4,578,764 by Hutchins et al.) 
was invented by Buote, is assigned to Zymark Corporation, and is 
incorporated herein by reference. 
While many prior art laboratory systems, such as the aforedescribed 
"PyTechnology.TM." system of Zymark Corporation, are capable of 
integration with a gas or liquid chromatographs, they are nevertheless 
deficient in several aspects. For example, Zymark's "GC Inject PySection" 
operates with an HP7673A automatic injector, HP5890A gas chromatograph, 
and HP3392A integrator, each of which is manufactured by Hewlett-Packard 
Company of Palo Alto, Calif., but lacks the compactness of size which is 
necessary to ensure quick transfers of samples. 
Zymark's "LC Inject PySection" also provides direct injection of prepared 
samples into an HPLC (i.e., high-performance liquid chromatograph), but it 
requires that the HPLC be located near the Zymark system which is not 
within reach of the robot. Furthermore, like many other prior art 
laboratory systems, the "PyTechnology.TM." system utilizes a robot which 
suffers from the disadvantage of having to be taught. 
SUMMARY OF THE INVENTION 
Accordingly, it is a general object of the present invention to provide 
laboratory apparatus for analyzing one or more samples each of which is 
contained in a respective vial. More specifically, it is an object of the 
present invention to provide a pre-injection sample sequencing subsystem 
and method for a laboratory system having chromatographic means which 
includes a column, a sample port atop the column, means for withdrawing 
the sample from its respective vial, and means for injecting the withdrawn 
sample into the column through the sample port. 
Another object of the present invention is to provide a pre-injection 
sample sequencing subsystem and method for such a laboratory system that 
optimizes the movements of the sample between a storage position, any 
pre-injection processing positions, and the sample port. 
Yet another object of the present invention is to provide a pre-injection 
sample sequencing subsystem and method for such a laboratory system that 
improves time-critical analyses performed by the system. 
Briefly, these and other objects are accomplished in accordance with the 
present invention by laboratory apparatus for analyzing one or more 
samples, each of which is contained in a respective vial. Such apparatus 
generally comprises chromatographic means for analyzing the samples, means 
for individually injecting same into a sample port, pre-injection sample 
processing means for processing preselected ones of the samples, tray 
means for holding the samples contained in their vials, and robotic means 
for transferring the samples. The tray means includes a plurality of 
physical locations each of which is adapted to store a single one of the 
samples, and a plurality of virtual locations each of which is adapted to 
juxtapose a single one of the samples to the pre-injection sample 
processing means. Accordingly, the robotic means includes controller means 
for sequencing the transfer of the samples between the physical and the 
virtual locations of the tray means, and the sample port. 
In accordance with one important aspect of the present invention, a 
pre-injection method of sequencing the samples between the physical and 
virtual locations of the tray means, and the sample port includes not only 
the steps of providing a circular tray that is attached to the 
chromatographic means, but also the steps of providing insertable means 
for holding the plurality of the samples, the holding means including the 
plurality of physical locations and virtual locations, and also of 
mounting such holding means to the chromatographic means such that one of 
the plurality of virtual locations corresponds to the sample port. 
In accordance with another important aspect of the present invention, such 
sample sequencing method further comprises the steps of providing 
pre-injection sample processing means for processing preselected ones of 
the samples, adapting each one of the virtual locations to juxtapose each 
of the samples to the sample processing means, identifying each of the 
samples and verifying the identification of each such sample prior to its 
transfer by the robotic means between the physical and virtual locations 
of the holding means, and the sample port. 
Other objects, advantages, and novel features in accordance with the 
present invention will become more apparent from the following detailed 
description of a preferred embodiment thereof, considered in conjunction 
with the accompanying drawings wherein:

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now to the drawings, wherein like numbers designate like or 
corresponding parts throughout each of the several views, there is shown 
in FIG. 1 laboratory apparatus 10 for analyzing one or more samples each 
of which is contained in a respective vial 12. 
The apparatus 10 as shown includes chromatographic means 14 for analyzing 
each of the samples, for example an HP5890A gas chromatograph which is 
manufactured by Hewlett-Packard Company of Palo Alto, Calif. As is known, 
such chromatographic means 14 includes a column 16 and a sample port 18 
atop the column 16. Such chromatographic means 14, therefore, is generally 
applicable to both gas and liquid chromatographs. 
As such, the chromatographic means 14 facilitates not only the introduction 
of a sample into a controlled stream of mobile phase at the top of the 
column 16, but also the continuous monitoring of the column effluent by a 
suitable detector (i.e., a device transducing chemical information into 
electrical signals--not shown), followed by a signal recording or by 
further processing of such recorded information. 
The laboratory apparatus 10 further comprises means 20 for individually 
injecting the samples into the sample port 18, pre-injection sample 
processing means 22 for processing preselected ones of the samples, tray 
means 24 for holding the samples contained in their vials 12, and robotic 
means 26 for transferring the samples between the tray means 24 and the 
sample port 18. 
One suitable such injecting means 20 is an HP7673A automatic on-column 
injector which is manufactured by Hewlett-Packard Company of Palo Alto, 
Calif. The precision of such known automatic on-column injecting means 20 
is clearly superior to manual injection since variability of injection 
technique between operators is eliminated. Moreover, sample discrimination 
is minimized due to fast injection and provisions are made for automated 
cool on-column capillary injection. 
Referring now also to FIG. 2, it can be seen that the tray means 24 and 
robotic means 26 suitably comprise an HP7673A automatic sampler which is 
also manufactured by Hewlett-Packard Company of Palo Alto, Calif. Such 
tray means 24 includes a circular tray 28 that is attached to the 
chromatographic means 14, means 30 for holding the samples in a plurality 
of concentric circular arrays 32, a robotic arm 34 that is adapted to be 
extended across such circular arrays 32 in the directions of the arrow as 
shown in FIG. 2, a hand 36, attached to one end of the arm 34, that is 
adapted to grasp a selected sample contained in its respective vial 12, 
and means 38 for controlling the transfer of the samples by the robotic 
means 26. 
In accordance with a presently preferred embodiment of this invention, the 
circular tray 28 is divided into four quadrants 40 in order to support 
removable inserts 42 which together comprise the holding means 30. Each of 
the inserts 42 are formed to hold twenty-five vials 12 containing 
respective samples. Accordingly, while the HP7673A automatic sampler 
comprising the tray means 24 and the robotic means 26 is operating, the 
inserts 42 may even be removed or installed without disrupting the 
sampling sequence. It is readily apparent, therefore, that maximum 
flexibility in the preparation and loading of samples is provided by the 
laboratory apparatus 10 as thus far described. 
The circular arrays 32 shown in FIG. 2 are formed by a plurality of linear 
arrays 44 of physical storage locations 46 extending radially outward from 
a central axis A of the circular tray 28, each one of the physical 
locations 46 adapted for storage of a single vial 12. Extending further 
outward from the central axis A from selected ones of the plurality of 
linear arrays 44 is one or more virtual locations 48, each of which is 
adapted to juxtapose a single sample-containing vial 12 to the 
pre-injection sample processing means 22. 
Each one of the physical locations 46 and virtual locations 48 is uniquely 
addressable by the controller means 38. For example, included within the 
controller means 38 for the pre-injection sample processing means 22 in 
accordance with a presently preferred embodiment of this invention is one 
or more circuit boards 50 for purposes of communication with the 
laboratory apparatus 10. Such controller means 38 may include a 
typewriter-like keyboard 52, and may be suitably comprised of the HP3393A 
integrator which is manufactured by Hewlett-Packard Company of Palo Alto, 
Calif. In accordance with a presently preferred embodiment of this 
invention, the circuit boards 50 are maintained within a power supply 
portion 25 of the HP7673A automatic sampler. 
In order to position samples for processing within the chromatographic 
means 14, rotary transfer means 54 is suitably provided with the on-column 
injecting means 20. Such rotary transfer means 54 temporarily stores a 
limited number of the samples contained in their vials 12, and juxtaposes 
a single sample so temporarily stored proximate to the sample port 18. As 
is shown in FIG. 2, the rotary transfer means 54 comprises a circular 
array of physical storage locations 56, wherein at least one of the 
physical storage locations 56 corresponds to one means 30, such that the 
robotic means 26 can transfer a sample between the tray means 24 and the 
injecting means 20. 
Many chromatographic applications require a certain amount of sample 
preparation before those samples can be introduced into the chromatograph 
(e.g., the addition of derivatization agents or internal standards, 
filtration, dilution, or solid phase extraction). Several of these 
functions are of a time-critical nature (e.g., heating of a sample to 
reduce its viscosity, or the addition of derivatization agents), and 
require certain particular processes to be performed on the sample 
immediately before its injection into the chromatographic column. The 
pre-injection processing means 28 provides such a means. 
Identification and verification of the identity of the samples is also the 
key to accurate chromatographic analyses. Such identification and 
verification must be performed on each sample both before and after it has 
been injected into the chromatographic column. Each of the vials 12 in 
accordance with another important aspect of the present invention includes 
an encoded label such as a bar code label (not shown) which is 
human-readable and machine readable. Means 58 is, therefore, provided on 
the tray means 24 for automatically reading the coded labels on each vial 
12. One suitable such means 58 is disclosed in a copending patent 
application of Engel et al., Ser. No. 142,974, filed Jan. 12, 1988, which 
is assigned to the assignee of the present invention and is incorporated 
herein by reference. 
In order to perform sample preparation functions, such as heating, the 
addition of derivatization agents or internal standards, dilution, 
filtration, or solid phase extraction, the pre-injection processing means 
28 of the present invention is mounted to the tray means 24 by one or more 
mounting brackets 60 and includes a vial holding block 62 upon a base 
portion 64. The vial holding block 62 has a pair of vial locations 
corresponding to a pair of virtual locations 48 of the tray means 24. In 
such a manner, therefore, the vial holding block 62 serves as a location 
to exchange vials 12 with the adjacent circular tray 28. One of the pair 
of vial locations on the vial holding block could suitably comprise a hole 
to dispose of unwanted samples, sample preparation glassware, solid phase 
extraction columns and filter cartridges. Through the simple insertion of 
a heater element and temperature sensor (not shown) into the vial holding 
block 62, the samples which were transferred from the tray means 24 to the 
pre-injection processing means 28 could be heated at programmed 
temperatures. 
An alternative system could utilize the convective transfer of heat via 
forced liquid or gas flow through a remotely heated block (not shown) to 
the vials 12, while a peltier cooler or forced flow of a coolant such as 
carbon dioxide could be used to allow samples to be cooled. The ability to 
weigh samples could also be implemented through the addition of a force 
transducer to the base 64, or by virtue of an analytical balance that 
would be accessible through the same disposal hole discussed immediately 
herein above. 
An elevator portion 66 is attached to the base portion 64 to provide a 
means of moving a vertical carriage 68 that is controlled by a circuit 
board 70. The carriage 68 is movable upwards and downwards upon a lead 
screw 71 driven by a rotary stepper or DC motor (not shown). Means such as 
a gripper (not shown) could be used to enable the carriage 68 to grasp, 
lift, and release vials 12, filters, or solid phase extraction columns. 
Alternatively, suitable needles 72 can be installed upon the carriage 68 
for various pre-injection sample processing steps. Hollow needles, for 
example, would permit a dispenser to add or withdraw liquid from the 
sample vials 12 contained in the vial holding block 62. A heated vial 
holding block 62 as was briefly discussed herein above would enable high 
temperature solvation and dilution along with derivatization. Grooved 
needles, on the other hand, would allow sample vials 12 to be purged with 
an inert gas. Furthermore, combining this function with a heated vial 
holding block 62 would also permit a programmed drying of the samples. A 
cavity (not shown) could also be added below the base portion 64 to enable 
the rinsing of the needles 72 with solvents pumped from a dispenser to 
reduce the potential for carryover. 
One of the circuit boards 50 suitably comprises a means providing power and 
communications with the pre-injection processing means 22 which enables 
the work station 52 to address one or more of the pre-injection processing 
means 22 via selected commands. An RS-485 communications bus (not shown) 
is preferably provided between such circuit board 50 and the pre-injection 
processing means 22. 
Another one of the circuit boards 50 comprises a means for interfacing with 
the work station 52 and other peripherals such as a host computer (not 
shown). Such interfacing suitably not only provides for overlapping of 
sample preparation and analysis as described in more detail herein below, 
but also provides for "token" level control of the on-column injection 
means 20, tray means 24, and robotic means 26, use of the on-column 
injection means 20 as a precision dispenser, elimination of any 
unnecessary "homing" of the robotic means 26 to increase effective speed 
of the sequencing subsystem, and the ability to manipulate vials 12 of 
varying sizes. The work station 52 may also include a conventional RS-232C 
serial interface. 
Still another one of the circuit boards 50 suitably comprises a means for 
controlling operation of the bar code reading means 58. In such a manner, 
therefore, the pre-injection processing means 22, or any other suitable 
means for conducting sample preparation functions may be attached directly 
to the tray means 24, and addressed by the controller means 38 via the 
virtual locations 48 at which such pre-injection processing means are 
attached. No teaching of the controller means 38 is necessary. 
Referring now to FIG. 3 in conjunction with FIGS. 1 and 2, a pre-injection 
sample sequencing method which utilizes the aforedescribed apparatus in 
accordance with the preferred embodiment of the present invention will now 
be explained. 
As noted herein above, it is an object of the present invention to provide 
a pre-injection sample sequencing subsystem and method for such a 
laboratory system that optimizes the movements of the sample between a 
storage position, any pre-injection processing positions, and the sample 
port. More importantly, however, it is an object of the present invention 
is to provide a pre-injection sample sequencing subsystem and method for 
such a laboratory system that improves time-critical analyses performed by 
the system. 
For example, crude oil may contain compounds that are not in solution at 
room temperature. In order to analyze such samples with a chromatograph 
for determination as to the existence of those compounds, therefore, the 
samples would first have to be heated. However, it may be undesirable to 
store the samples hot as volatile components may be lost. Careful 
sequencing of the samples through various pre-injection processing steps 
becomes necessary for accurate chromatographic analysis. 
In a laboratory system 10 having chromatographic means 14 for analyzing a 
sample contained in a vial 12, Wherein the chromatographic means 14 
includes a column 16, a sample port 18 atop the column 16, on-column means 
20 both for withdrawing the sample from the vial and for injecting the 
withdrawn sample into the column through the sample port, and means for 
processing 22 the sample prior to its withdrawal from its vial 12, 
therefore, a method of sequencing a plurality of the samples between the 
processing means and the withdrawing and injecting means generally 
comprises the steps of: 
(1) providing a circular tray 28 that is attached to the chromatographic 
means 14, the circular tray 28 including a central axis A; 
(2) providing means for holding 30 the plurality of the samples, the 
holding means 30 including a plurality of physical locations 46 each of 
which is adapted for storage of a single vial 12, and a plurality of 
virtual locations 48 each of which is adapted to juxtapose a single vial 
12 with the processing means 22; 
(3) mounting the holding means 30 to the chromatographic means 14 such that 
one of the plurality of virtual locations 48 is proximate to the sample 
port 18; 
(4) providing robotic means 26, including an arm 34 an a hand 36 attached 
to the arm 34, for transferring a single vial 12 between its respective 
physical location 46 and selected ones of the plurality of virtual 
locations 48 including the sample port 18; and, 
(5) controlling the robotic means 26 to optimize movement thereof for 
transferring a single vial 12 between its respective physical location 46 
and the selected ones of said plurality of virtual locations 48. 
The step of providing the holding means 30 suitably comprises the steps of: 
providing more than one circular array 32 of the physical locations 46 
which are disposed concentrically about the central axis A; disposing each 
physical location 46 in a respective one of the circular arrays 32 in a 
linear array 44 of the physical locations 46 extending radially outward 
from the central axis A; and disposing each one of the virtual locations 
48 as an extension of one of the linear arrays 44. 
As was explained herein above with reference to the laboratory apparatus 
10, the method according to a presently preferred embodiment further 
comprises the step of providing the on-column means 20 with rotary 
transfer means 54 for temporarily storing a limited number of samples 
contained in their vials 12, and for juxtaposing a single one of that 
limited number of samples so temporarily stored proximate to the sample 
port 18. The rotary transfer means 54 may preferably comprise a circular 
array of physical storage locations 56, wherein at least one of those 
storage locations 56 of the circular array 54 in the rotary transfer means 
54 corresponds to one of the plurality of virtual locations 48 of the 
holding means 30. 
As is best illustrated by FIG. 3, the controlling step of the sequencing 
method according to the present invention comprises the steps of: 
(a) assigning a unique address to each one of the physical and virtual 
locations 46, 48 of the holding means 30; 
(b) instructing the robotic means 26 via the circuit cards 50 to retrieve a 
selected sample from its respective physical location 46; 
(c) retrieving the selected sample with the robotic means 26; 
(d) instructing the robotic means 26 to transfer the selected sample from 
its respective physical location 46 to the processing means 22; 
(e) transferring the selected sample with the robotic means 26 to the 
processing means 22; 
(f) instructing the processing means 22 to conduct at least two 
pre-injection processing steps upon the selected sample; 
(g) conducting one of the at least two pre-injection processing steps upon 
the selected sample with the processing means 22; 
(h) conducting other ones of the at least two pre-injection processing 
steps upon selected sample with the processing means 22; 
(i) instructing the robotic means 26 to retrieve another selected sample 
from its respective physical location 46; 
(j) retrieving the other selected sample with the robotic means 26 during 
the conduct of the other pre-injection processing steps on a previously 
selected sample; 
(k) instructing the robotic means 26 to transfer the other selected sample 
to the processing means 22; 
(l) transferring the other selected sample with the robotic means 26 to the 
processing means 22 during the conduct of said other pre-injection 
processing steps on the previously selected sample; 
(m) instructing the robotic means 26 to retrieve the previously selected 
sample from the processing means 22 upon completion of the other 
pre-injection processing steps; 
(n) retrieving the previously selected sample with the robotic means 26 
from the processing means 22 upon completion of the at least two 
pre-injection processing steps; 
(o) instructing the robotic means 26 to transfer the previously selected 
sample to the virtual location 48 of the holding means 30 that corresponds 
to the at least one of said physical storage locations 56 of the circular 
array in the rotary transfer means 54; 
(p) transferring the previously selected sample with the robotic means 26 
to the virtual location 46 of the holding means 30 that corresponds to the 
at least one of the physical storage locations 56 of the circular array in 
the rotary transfer means 54; 
(q) instructing the rotary transfer means 54 to transfer the previously 
selected sample to the sample port 18; 
(r) instructing the on-column means 20 to withdraw the previously selected 
sample from its vial 12; 
(s) instructing the on-column means 20 to inject the withdrawn sample into 
the column 16 through the sample port 18; and 
(t) repeating steps (f) through (s) for the other selected sample 
The method according to this presently preferred embodiment of this 
invention, may further comprise the steps of: identifying each selected 
sample (e.g., by a bar code label); instructing the robotic means 26 to 
transfer the selected sample to the processing means 22 by communication 
of its unique address; rotating the arm 34 about the central axis A to 
align the hand 36 with the particular one of the linear arrays 44 that 
corresponds to the selected sample; extending the hand 36 to the physical 
location 46 of the holding means 30 that corresponds to the selected 
sample; grasping the selected sample with the hand 36; and verifying the 
identity of each selected sample prior to its transfer to the processing 
means 22. Such verification may be suitably performed in accordance with 
the method and apparatus described in copending Ser. No. 142,974. 
For a plurality of such samples, referring now more specifically to FIG. 3, 
the sequencing method according to the present invention takes a first 
sample with the robotic means 24 and places it in the bar code reading 
means 58 where the bar code label (not shown) on the vial 12 of the first 
selected sample is read at time t1. After verification by the controller 
means 38, the first sample is taken to the pre-injection processing means 
22 where, for example, a solvent could be dispensed at time t2 through the 
needles 72 into that first sample. 
Thereafter, at the pre-injection processing means 22 or other suitable such 
means that are disposed at other virtual locations 48 around the tray 
means 24, the first sample would be agitated at time t3 and heated for a 
period of time commencing at time t4, any necessary transfer of the first 
sample being performed by the robotic means 26. 
While the first sample is completing the heating step, the robotic means 26 
would take another sample and transfer it to the bar code reading means 58 
where the bar code label (not shown) on the vial 12 of the second selected 
sample would be read at time t5. Thereafter, similar dispensing, agitation 
and heating pre-injection processing steps would be performed respectively 
on the second sample at times t6, t7 and t8. In order to then optimize 
such pre-injection processing, the first sample would be retrieved by the 
robotic means 26, transferred to the virtual location 48 corresponding to 
the rotary transfer means 54 of the on-column injection means 20, rotated 
by such rotary transfer means 54 to the sample port 18 and be injected at 
time t9 into the column 16. The first sample vial 12 would then be 
discarded at time t1O, and the robotic means 26 would be returned to a 
"home" position at time t11. 
Almost immediately thereafter, and while the second sample was still being 
heated, a third sample could be retrieved by the robotic means 26 and 
transferred to the bar code reading means 58 where the bar code label (not 
shown) on the vial 12 of that third selected sample would be read at time 
t12. Again, similar dispensing, agitation and heating pre-injection 
processing steps would be performed respectively on the third sample at 
times t13, t14 and t15. In order to continue optimizing such pre-injection 
processing, the second sample would be retrieved by the robotic means 26, 
transferred to the virtual location 48 corresponding to the rotary 
transfer means 54 of the on-column injection means 20, rotated by such 
rotary transfer means 54 to the sample port 18 and be injected at time t16 
into the column 16. The second sample vial 12 would then be discarded at 
time t17, and the robotic means 26 would be returned to its "home" 
position at time t18. 
Obviously, many modifications and variations of the present invention are 
possible in light of the foregoing teachings. It is to be understood, 
therefore, that within the scope of the appended claims, the present 
invention may be practiced otherwise than as is specifically disclosed 
herein.