Abstract:
A knowledge management platform eliminates the trial and error process for analytical chemists in, for example, identifying appropriate methodologies for separating mixtures of chemical compounds. The platform allows the analytical chemists to perform a variety of searches on data existing from previous experiments, procedures, and/or processes. The platform may be employed to make faster decisions, and ultimately decreases the time taken in selecting an appropriate separation methodology.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority to and the benefit of, and incorporates herein by reference in its entirety, U.S. Provisional Patent Application No. 61/384,822, which was filed on Sep. 21, 2010. 
     
    
     TECHNICAL FIELD 
       [0002]    In various embodiments, the present invention relates to systems, methods, and apparatus for facilitating chemical analyses. More specifically, described herein are exemplary systems, methods, and apparatus for determining methodologies, and the parameters thereof, to separate substances. 
       BACKGROUND 
       [0003]    A typical day for an analytical chemist often includes performing a variety of chemical analyses, including the development of methodologies and procedures to separate mixtures of compounds in reaction batches, the deconvolution of degradation products, and/or the validation of product specifications. The methodologies used to analyze and separate mixtures of chemical compounds generally involve various machine settings, detector settings, and materials suitable to perform the separation. Unfortunately, to determine an appropriate methodology to be utilized in separating one or more chemical compounds from a sample, the analytical chemist typically has to employ a time-consuming and costly trial and error process utilizing his or her own experience and training. 
         [0004]    The results of the analytical chemist&#39;s method runs may be stored in, for example, a scientific data management system (SDMS), a laboratory information management system (LIMS), or in any of a variety of other databases or digital library systems. However, using existing systems, the analytical data is often stored in such a way that very few other analytical chemists, even within the same laboratory, are able to thereafter effectively reuse the methodologies from those historical experiments, procedures, and/or processes. 
         [0005]    For example, when wanting to separate a molecule that an analytical chemist in a laboratory worked with several months prior, another analytical chemist within that laboratory will typically undertake another time-consuming and costly trial and error process to determine the appropriate machine settings, detector settings, and materials to perform the separation. Complicating matters is the fact that data from previous separation runs are normally stored on a variety of different machines used in the laboratory, making it more difficult to determine what separation methodologies were successfully employed in the past. 
         [0006]    As such, needs exist for improved procedures for facilitating chemical analyses, such as the development of separation methodologies, the deconvolution of degradation products, and the validation of product specifications. 
       SUMMARY OF THE INVENTION 
       [0007]    Described herein are various embodiments of systems, methods, and apparatus that eliminate the trial and error process for analytical chemists in, for example, identifying appropriate methodologies for separating mixtures of compounds, deconvolving degradation products, and/or validating product specifications. In one embodiment, a knowledge management platform is provided that allows scientists, such as analytical chemists, to perform a variety of searches on data existing from previous experiments, procedures, and/or processes that may have been stored in a disorganized manner in order to find the best methodology to separate molecules. Advantageously, the platform connects methodologies, structures, and parameters that may be scattered across disparate, and physically separate, information stores, and may present to the user thereof (e.g., the analytical chemist) a single, searchable repository. As such, the platform may be employed to make faster decisions, and ultimately decreases the time taken in selecting an appropriate methodology. 
         [0008]    In general, in one aspect, embodiments of the invention feature an apparatus for electronically identifying a separation method for separating one or more chemical compounds in a sample. The apparatus includes a memory for storing a relational database, a memory for storing a code defining a set of instructions, and a processor for executing the set of instructions. The code may include a search module. The memory for storing the relational database may be the same or a different memory from that which is used for storing the code. 
         [0009]    The relational database includes data harvested from one or more other databases (e.g., a laboratory information management system (LIMS), a scientific data management system (SDMS), an electronic laboratory notebook, another relational database, a web page, and/or a searchable text file) that contain(s) experimental run data from completed separation experiments. The data in the relational database may be actively accessed from the one or more other databases, or the data may be copied from the one or more other databases into a consolidated database (i.e., the relational database). A set of separation method properties and a set of separation run properties from the harvested data are linked in the relational database to each of a plurality of chemical structure objects corresponding to one or more compounds separated in the completed separation experiments, and each of the one or more chemical structure objects is associated with a corresponding set of chemical structure properties in the relational database. The correlated separation method properties, separation run properties, and chemical structure properties are indexed and stored in the relational database. 
         [0010]    For its part, the search module is configured to identify and display one or more chemical structures and corresponding separation method properties, separation run properties, and, optionally, chemical structure properties, in response to a user query of the relational database. 
         [0011]    In various embodiments, the user query comprises two or more chemical structures or substructures as input, and the search module is configured to identify and display separation method properties and separation run properties common to all of the two or more chemical structures or substructures. 
         [0012]    In one embodiment, the separation method properties include one or more text-based, numeric, and/or alphanumeric strings and/or ranges, such as a method name, a mobile phase indicator, a temperature, a temperature range, a flow rate, a flow rate range, a gradient method indicator, a wavelength, a wavelength range, an instrument name, a column name, a column particle size, a column length, and a column internal diameter. The separation run properties may include one or more text-based, numeric, and/or alphanumeric strings and/or ranges, such as a sample name, a vial number, a run date, a run date range, a process date, a process date range, a scientist name, a run time, a run time range, an injection number, an injection number range, an injection volume, and an injection volume range. For their part, the chemical structure properties may include one or more text-based, numeric, and/or alphanumeric strings and/or ranges, such as a compound number, a compound name, an IUPAC name, a molecular weight, a molecular weight range, a CLogP, a CLogP range, a molar volume, and a molar volume range. 
         [0013]    In one embodiment, the search module is configured to identify and display via a graphical user interface, in response to the user query, a plurality of graphical representations of chemical structures from the relational database corresponding to one or more of: (A) a user-identified structure, (B) one or more substructures within the user-identified structure, (C) one or more structures containing the user-identified structure as a substructure therein, (D) one or more structures that are chemically similar to the user-identified structure, and/or (E) one or more structures corresponding to chemical compounds separated using separation method properties, separation run properties, and/or chemical structure properties identified in the user query. In addition, the search module may be further configured to, upon selection by the user of one of the chemical structures that are graphically represented on the graphical user interface, identify and display the separation method properties, separation run properties, and, optionally, chemical structure properties from the relational database corresponding to the user-selected chemical structure. 
         [0014]    In another embodiment, the search module is further configured to archive data corresponding to the user query and query results in the relational database, thereby facilitating later data retrieval in response to a future user query. 
         [0015]    In general, in another aspect, embodiments of the invention feature a procedure for electronically identifying a separation method for separating one or more chemical compounds in a sample. The procedure includes harvesting data from one or more databases (e.g., a laboratory information management system (LIMS), a scientific data management system (SDMS), an electronic laboratory notebook, a relational database, a web page, and/or a searchable text file) that contain(s) experimental run data from completed separation experiments. The procedure also includes correlating a set of separation method properties and a set of separation run properties from the harvested data with one or more chemical structure objects corresponding to one or more compounds separated in the completed separation experiments. Each of the one or more chemical structure objects is associated with a corresponding set of chemical structure properties. In addition, the procedure includes indexing and storing the correlated separation method properties, separation run properties, and chemical structure properties in a relational database, and displaying one or more chemical structures and corresponding separation method properties, separation run properties, and, optionally, chemical structure properties, in response to a user query of the relational database. 
         [0016]    In various embodiments, the user query includes two or more chemical structures or substructures as input, and the separation method properties and separation run properties common to all of the two or more chemical structures or substructures are displayed in response to the user query. 
         [0017]    In one embodiment, the separation method properties include one or more text-based, numeric, and/or alphanumeric strings and/or ranges, such as a method name, a mobile phase indicator, a temperature, a temperature range, a flow rate, a flow rate range, a gradient method indicator, a wavelength, a wavelength range, an instrument name, a column name, a column particle size, a column length, and a column internal diameter. The separation run properties may include one or more text-based, numeric, and/or alphanumeric strings and/or ranges, such as a sample name, a vial number, a run date, a run date range, a process date, a process date range, a scientist name, a run time, a run time range, an injection number, an injection number range, an injection volume, and an injection volume range. For their part, the chemical structure properties may include one or more text-based, numeric, and/or alphanumeric strings and/or ranges, such as a compound number, a compound name, an IUPAC name, a molecular weight, a molecular weight range, a CLogP, a CLogP range, a molar volume, and a molar volume range. 
         [0018]    In one embodiment, displaying the one or more chemical structures and corresponding separation method properties, separation run properties, and, optionally, chemical structure properties, in response to the user query of the relational database, includes displaying via a graphical user interface a plurality of graphical representations of chemical structures from the relational database corresponding to one or more of (i) a user-identified structure, (ii) one or more substructures within the user-identified structure, (iii) one or more structures containing the user-identified structure as a substructure therein, (iv) one or more structures that are chemically similar to the user-identified structure, and/or (v) one or more structures corresponding to chemical compounds separated using separation method properties, separation run properties, and/or chemical structure properties identified in the user query. Upon selection by the user of one of the chemical structures that are graphically represented on the graphical user interface, the separation method properties, separation run properties, and, optionally, chemical structure properties from the relational database corresponding to the user-selected chemical structure may be displayed. 
         [0019]    In another embodiment, data corresponding to the user query and the query results is archived in the relational database, thereby facilitating later data retrieval in response to a future user query. 
         [0020]    Elements of embodiments described with respect to a given aspect of the invention may be used in various embodiments of another aspect of the invention. For example, it is contemplated that features of dependent claims depending from one independent claim can be used in apparatus, systems, and/or methods of any of the other independent claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]    The foregoing and other objects, aspects, features, and advantages of the invention will become more apparent and may be better understood by referring to the following description taken in conjunction with the accompanying drawings, in which: 
           [0022]      FIG. 1  is a block diagram of a system for facilitating chemical analyses in accordance with an illustrative embodiment of the invention; 
           [0023]      FIG. 2  is an image of a method search screen for inputting method properties and run details, in accordance with an illustrative embodiment of the invention; 
           [0024]      FIG. 3  is an image of a structure search screen for inputting one or more chemical structures and/or structure properties, in accordance with an illustrative embodiment of the invention; 
           [0025]      FIG. 4  is an image of a search results screen displaying chemical structures, structure properties, method properties, and run details, in accordance with an illustrative embodiment of the invention; 
           [0026]      FIG. 5  is an image of a method properties screen displaying information associated with a particular method, in accordance with an illustrative embodiment of the invention; 
           [0027]      FIG. 6  is an image of a structure details screen displaying information associated with a particular chemical structure, in accordance with an illustrative embodiment of the invention; 
           [0028]      FIG. 7  is an image of a run details screen displaying information associated with a particular run, in accordance with an illustrative embodiment of the invention; 
           [0029]      FIG. 8  is an image of a structure search screen displaying two chemical structures, in accordance with an illustrative embodiment of the invention; and 
           [0030]      FIG. 9  is an image of a search results screen displaying the results for a search to find separation methods for two structures, in accordance with an illustrative embodiment of the invention. 
       
    
    
     DESCRIPTION 
       [0031]    In general, in various embodiments, the present invention pertains to systems, methods, and apparatus for facilitating chemical analyses. In broad overview, in accordance with one embodiment of the invention, a user (e.g., an analytical chemist) employs a computing system to rapidly identify one or more methodologies appropriate for separating mixtures of compounds, deconvolving degradation products, and/or validating product specifications. In particular, in one embodiment, the computing system employs algorithms to connect together the discrete methodologies, structures, and parameters that may be scattered across otherwise unconnected databases, instruments, etc., and then suggests to the user the best method(s) to utilize in performing the separation and analytical analysis. 
         [0032]      FIG. 1  depicts a system  100 , according to an illustrative embodiment of the invention, for facilitating chemical analyses. The system  100  includes a client node  104 , a server node  108 , a relational database  110 , multiple additional databases  112   1 - 112   N  (which, in one embodiment, are disparate and physically separate from one another), and, for enabling communications therebetween, a network  116 . As illustrated, the server node  108  may include a search module  120  and a display module  124 . 
         [0033]    The network  116  may be, for example, a local-area network (LAN), such as a company or laboratory Intranet, a metropolitan area network (MAN), or a wide area network (WAN), such as the Internet. Each of the client node  104 , server node  108 , relational database  110 , and additional databases  112   1 - 112   N  may be connected to the network  116  through a variety of connections including, but not limited to, standard telephone lines, LAN or WAN links (e.g., T1, T3, 56 kb, X.25), broadband connections (e.g., ISDN, Frame Relay, ATM), or wireless connections. The connections, moreover, may be established using a variety of communication protocols (e.g., HTTP, TCP/IP, IPX, SPX, NetBIOS, NetBEUI, SMB, Ethernet, ARCNET, Fiber Distributed Data Interface (FDDI), RS232, IEEE 802.11, IEEE 802.11a, IEEE 802.11b, IEEE 802.11g, and direct asynchronous connections). 
         [0034]    The client node  104  may be any type of personal computer, Windows-based terminal, network computer, wireless device, information appliance, RISC Power PC, X-device, workstation, mini computer, main frame computer, personal digital assistant, set top box, handheld device, or other computing device that is capable of both presenting information/data to, and receiving commands from, a user of the client node  104  (e.g., an analytical chemist). The client node  104  may include, for example, a visual display device (e.g., a computer monitor), a data entry device (e.g., a keyboard), persistent and/or volatile storage (e.g., computer memory), a processor, and a mouse. In one embodiment, the client node  104  includes a web browser, such as, for example, the INTERNET EXPLORER program developed by Microsoft Corporation of Redmond, Wash., to connect to the World Wide Web. 
         [0035]    For its part, the server node  108  may be any computing device that is capable of receiving information/data from and delivering information/data to the client node  104 , for example over the network  116 , and that is capable of querying, receiving information/data from, and delivering information/data to the relational database  110  and/or additional databases  112   1 - 112   N . For example, as further explained below, the server node  108  may receive a search query from a user of the client node  104 , query the relational database  110  and receive search results therefrom, and present the search results to the user at the client node  104 . The server node  108  may include a processor and persistent and/or volatile storage, such as computer memory. 
         [0036]    Each database  112   1 - 112   N  may be any computing device that is capable of storing and managing collections of data, such as data relating to methodologies that may be used in separating mixtures of compounds. For example, each database  112   1 - 112   N  may store experimental run data from completed separation experiments, such as appropriate machine settings, detector settings, and materials to perform the work. Each database  112   1 - 112   N  may communicate using SQL or another language, or may use other techniques to store, receive, and transmit data. 
         [0037]    As used herein, the term “database” is broadly used to refer to any repository of information. For example, a database  112   1 - 112   N  may be a scientific data management system (SDMS), a laboratory information management system (LIMS), a relational database, an electronic laboratory notebook, or a computing device or any information store storing a web page, a searchable text file, PowerPoint slides, an Excel spreadsheet, etc. In addition, a database  112   1 - 112   N  can be any information store storing the files output by an instrument used in chemical analyses, whether that be a computer memory onboard the instrument itself or a separate information store to which the output files of the instrument have been transferred. Exemplary instruments that may be used in chemical analyses include, but are not limited to, the Agilent 1100 instrument manufactured by Agilent Technologies of Santa Clara, Calif.; the Acquity UPLC, the Trizaic UPLC, and the Method Station X5 SFC manufactured by Waters Corporation of Milford, Mass.; the UltiMate 3000 HPLC manufactured by Dionex Corporation of Sunnyvale, Calif.; and the Flexar FX-15 UHPLC manufactured by Perkin Elmer of Waltham, Mass. 
         [0038]    For its part, the relational database  110  is, in one embodiment, any computing device that is capable of receiving commands/queries and information/data from, and of delivering information/data to, the server node  108  and/or the client node  104 . In one embodiment, the databases  112   1 - 112   N  are disparate and physically separate databases, and the relational database  110  is a centralized database that stores and manages collections of data harvested from one or more of the databases  112   1 - 112   N . Again, the relational database  110  may communicate using SQL or another language, or may use other techniques to store, receive, and transmit data. 
         [0039]    The data stored within the relational database  110  may be harvested from the additional databases  112   1 - 112   N  in any manner. For example, the data may be actively accessed from the additional databases  112   1 - 112   N  or copied therefrom. In one embodiment, the harvesting is performed utilizing indexing and structure recognition algorithms, and the harvested data is connected together by examining and correlating the disjointed information that is found. For example, a set of separation method properties and a set of separation run properties (which are further described below) obtained from the harvested data may be linked in the relational database  110  to each of a plurality of chemical structure objects corresponding to one or more compounds that were separated in the completed separation experiments. The chemical structure objects may be, for example, of the type described in co-pending U.S. patent application Ser. No. 13/100,217 (e.g., computerized representations identifying various atoms, bonds, etc.), and each such chemical structure object may be associated with a corresponding set of chemical structure properties in the relational database  110 . The entire content of co-pending U.S. patent application Ser. No. 13/100,217 is hereby incorporated herein by reference. Once the separation method properties, the separation run properties, and the chemical structure properties are correlated, they may then be indexed and stored in the relational database  110 . 
         [0040]    The search module  120  and the display module  124  of the server node  108  may each be implemented as any software program and/or hardware device, for example an application specific integrated circuit (ASIC) or a field programmable gate array (FPGA), that is capable of providing the functionality described below. It will be understood by one having ordinary skill in the art, however, that the illustrated modules  120  and  124 , and the organization of the server node  108 , are conceptual, rather than explicit, requirements. For example, the two illustrated modules  120  and  124  may be combined into a single module, such that the functions performed by the two modules  120  and  124 , as described below, are in fact performed by the single module. In addition, it should be understood that any single one of the illustrated modules  120  and  124  may in fact be implemented as multiple modules, such that the functions performed by the single module, as described below, are in fact performed by the multiple modules. 
         [0041]    Although not shown in  FIG. 1 , each of the client node  104 , the server node  108 , the relational database  110 , and the additional databases  112   1 - 112   N  may also include its own transceiver (or separate receiver and transmitter) that is capable of receiving and transmitting communications, including requests, responses, and commands, such as, for example, inter-processor communications and networked communications. The transceivers (or separate receivers and transmitters) may each be implemented as a hardware device, or as a software module with a hardware interface. 
         [0042]    It will also be understood by those skilled in the art that  FIG. 1  is a simplified illustration of the system  100  and that it is depicted as such to facilitate the explanation of the present invention&#39;s embodiments. Moreover, the system  100  may be modified in a variety of manners without departing from the spirit and scope of the invention. For example, rather than both being implemented on a single server node  108 , the illustrated modules  120  and  124  may instead each be implemented on a different computing device (not shown) and such computing devices may communicate with one another directly, over the network  116 , or over another additional network (not shown). In yet another example, the functionality of the relational database  110  may in fact be resident on the server node  108  (e.g., be implemented in the computer memory thereof). Additional options are for the server node  108  and/or the relational database  110  to be local to the client node  104  (such that they may all communicate directly without using the network  116 ), or for the functionality of the server node  108  and/or the relational database  110  to be implemented on the client node  104  (e.g., for the search module  120 , the display module  124 , and/or the relational database  110  to reside on the client node  104 ). As such, the depiction of the system  100  in  FIG. 1  is non-limiting. 
         [0043]    In certain embodiments, the system  100  accelerates the process of developing a method to separate chemical compounds by mining and utilizing existing data sets to suggest methods and procedures that work against new molecules requiring testing. For example, when a user executes a search for a desired chemical structure, the system  100  may display one or more separation methods that have been used previously to separate that structure. When the user selects one of these methods, the system  100  may then display one or more runs (e.g., tests, experiments, or measurements) that have been performed using that method. Each displayed structure, method, and/or run may include a link to one or more screens that display the details of the corresponding selection. The details may be viewed simultaneously so that a user can compare and contrast the differences between the individual runs, molecules, or methods from the plurality of choices resulting from the query. As previously described, the relational database  110  is obtained by harvesting information from a plurality of data sources. In general, the harvesting process occurs before correlation of the data, which may take place prior to populating the relational database  110 . User querying, selection, and comparison activities generally occur after the relational database  110  has been populated. 
         [0044]    In certain embodiments, the system  100  correlates individual substances (e.g., molecules, biologics, enzymes, and proteins) that were separated in a run (e.g., a test or measurement) to information contained in other systems that capture and track method and run data, but not substance data. While the substance data may be missing key components, the system  100  back-fills those missing components by crawling or searching ancillary systems that may not be related to method development or run execution, and by associating the information found in an amalgamated system that makes correlation of the run/method/substance information possible. A query engine is then layered upon the data so that users can query against this highly dimensional information in an easy to use manner. As further described below, the system  100  returns the results as a combination of visual images and tables that are combined and that interact with one another so that large volumes of this information can be filtered and visualized quickly. 
         [0045]    A person or organization may use the system  100  to rationalize data and information from legacy systems. A user of the system  100  is able to query this data and information, run simulations, and/or develop hypotheses before any actual work commences. 
         [0046]    While the system  100  may be used to target methods for separating substances, the general process and algorithms used by the system  100  for harvesting, indexing, and storing data, coupled with the advanced query and display technologies, can be applied to other methods. For the example, the system  100  may be used to search for food science methods, engineering methodologies, business process methodologies, and other business practices that follow a repetitive and complex workflow with many dimensions of data that are stored. 
         [0047]    In certain embodiments, the system  100  produces a suggested method for use by the querying user. This method can then be applied to the real world process in a more efficient manner. The method can then be stored as an electronic record for future use or for use in a validated and/or controlled environment. 
         [0048]    In certain embodiments, the systems, procedures, and apparatus described herein allow a user to search for the best method (e.g., a method of separating a chemical compound from a mixture) by querying the system  100  using a single search parameter or a combination of parameters. For example, referring to  FIGS. 2 and 3 , the system  100  allows the user to search by method properties, run details, and/or structure properties. 
         [0049]      FIG. 2  is an image of a method search screen  200  for inputting method properties and run details, according to an embodiment of the invention. As depicted, method properties may include method name, temperature, mobile phase, flow rate, wavelength, gradient methods, column name, and/or instrument name. Additional method properties may include a column particle size, a column length, and/or a column internal diameter. Examples of method names include metabolite quantification, quality control of Guizhi Fuling capsules, multi-inlet TOF-MS, and KMD methylated. Temperatures, flow rates, and wavelengths (e.g., in mm) may be searched as numerical ranges. Gradient methods are typically searched as a yes or no choice. Instrument names are typically trade names or brand names of the instruments, such as A1100 (for the AGILENT 1100 instrument), ACQUITY UPLC, TRIZAIC UPLC, METHOD STATION X5 SFC, ULTIMATE 3000 UHPLC, and FLEXAR FX-15 UHPLC. Column names are typically trade names, such as CHIRALPAK ID, KINETEX PFP, KINETEX PHENYL-HEXYL, C8, C18, and STANDARD WIDEPORE C5. Sometimes a dimension will be included, such as LUNA 3 μm C18(2) 100 Å150×4.6 mm and GEMINI-NX 5 μm C18 110 Å150×4.6 mm. Run details may include sample name (typically a text string), vial (typically an alpha numeric string), run date, process date, scientist(s), run time, injection number, and/or injection volume. 
         [0050]    In certain embodiments, the mobile phase may be any text based string. Examples of mobile phases that may be queried or utilized include HPLC grade water with 0.1% formic acid, and acetonitrile with 0.1% formic acid. These two examples include a solvent plus a buffer (i.e., formate as formic acid). Other possible buffers include phosphate, citrate, formate, acetate, tris(hydorxymethyl) aminomethane, ammonia, borate, and/or diethylamine. Any combination of the following exemplary mobile phase solvents may also be used: cyclohexane, n-hexane, 1-chlorobutane, carbon tetrachloride, i-propyl ether, toluene, diethyl ether, tetrahydrofuran, chloroform, ethanol, ethyl acetate, dioxane, methanol, acetonitrile, nitromethane, ethylene glycol, and water. 
         [0051]    As depicted in  FIG. 2 , in certain embodiments, the method search screen  200  includes one or more dropdown menus, buttons, and/or cells or fields that the user may access to select or input search criteria using an input device, such as a mouse or keyboard. As depicted, the method search screen  200  includes a search button  202  that the user may select to begin a search. The method search screen  200  also includes a reset button  204  that the user may select to reset or clear the displayed search criteria. 
         [0052]      FIG. 3  is an image of a structure search screen  300  for inputting one or more chemical structures and/or structure properties, according to an embodiment of the invention. As depicted, structure properties may include structure name (e.g., IU PAC name, or compound name), weight, cLogP, and molar volume. Additional structure properties may include LogD, melting point, boiling point, # of H donors or acceptors, pKa, and/or refraction index. In one embodiment, any combination of the method properties, run details, and structure properties may be entered by the user and searched by the system  100 . 
         [0053]    In certain embodiments, the structure search screen  300  includes structure buttons  302  and element buttons  304  that the user may select to build and display one or more chemical structures to be searched. For example, the user may add a benzene ring to a chemical structure by selecting a benzene ring button. Similarly, the user may add a nitrogen atom to a structure by selecting an “N” button. In another embodiment, structures may be copied or imported from other sources, such as CHEMDRAW, available from Perkin Elmer of Waltham, Mass. As depicted, the structure search screen  300  may include a search button  306  and a reset button  308  for initiating a search and resetting input data, respectively. 
         [0054]    In certain embodiments, once the desired structure(s) has been created or obtained by the user, the system  100  allows the user to search (i) by substructure (i.e., the user can find methods through a substructure search), (ii) by similarity (i.e., the user can find methods through a similarity search of a drawn structure), or (iii) for separation methods for two or more structures (i.e., the user can request the system  100  to find the best methods for separating two or more drawn structures). Any of these searches may be performed with additional search criteria, such as one or more method properties and/or run details. Radio buttons may be selected by the user to identify the desired type of search. For example, in the embodiment depicted in  FIG. 3 , the user may select a first radio button  310  to search by substructure. In this case, the system  100  finds methods that have been used to separate structures having a desired substructure. Similarly, a second radio  312  button may be selected to search by similarity to find methods that have been used to separate similar structures. When evaluating the similarity of structures, the search module  120  may use, for example, a Tanimoto score and/or a Jaccard index. For example, the results may be ranked with a Tanimoto score indicating the similarity between the desired structure and the structures in the search results. A third radio button  314  may be selected to search for separation methods for two or more desired structures. With the third radio button  314  selected, the search module  120  will scan the relational database  110  to find methods for separating both of the drawn structures. 
         [0055]    After the user has input the desired search criteria (i.e., method properties, run details, and/or structure properties), the user directs the system  100  to perform the search by selecting one of the search buttons  202 ,  306 . The search module  120  then accesses the relational database  110  or the databases  112  and identifies search results that satisfy the search criteria. The display module  124  then displays the search results for the user. For example, the user may search for methods having a method name of “KMD Methylated.” To perform this search, the user enters “KMD Methylated” in the method name cell of the method search screen  200 . The user then selects the search button  202  and the system  100  returns all methods containing the name “KMD Methylated.” Similarly, the user may search for runs (e.g., tests or measurements) associated with a particular injection number. After the user enters the desired injection number in the method search screen  200 , the system  100  returns all runs associated with that injection number. As another example, the user may request a search for structures having a weight less than  300  daltons and cLogP less than 3.0, and the system  100  will identity structures that satisfy these criteria. In certain embodiments, any combination of method properties, run properties, and/or structure properties may be searched. 
         [0056]      FIG. 4  is an image of a search results screen  400  depicting the results of a search for method names that include the term “halo,” in accordance with one embodiment of the invention. As depicted, the search results include two methods  402  having “halo” in the method name. In addition to identifying these two methods, the system  100  returned run properties  404 , structures  406 , and structure properties  408  associated with the two methods. For example, the search results include images or graphical representations of structures  406  associated with the two methods. The search results also include details about the structure properties  408 , the methods  402 , and the run properties  404 , associated with the two methods. In another embodiment, the user may sort the tabulated results by selecting a column header. 
         [0057]    In certain embodiments, the images of the structures  406  provided in the search results screen  400  may correspond to (A) a user-identified structure (e.g., a structure drawn by the user), (B) a substructure within the user-identified structure, (C) a structure containing the user-identified structure as a substructure therein, and/or (D) a structure that is chemically similar to the user-identified structure. In one embodiment, upon selecting an image of a structure  406 , the system  100  displays additional information about the structure  406 , such as separation method properties, separation run properties, and/or chemical structure properties, corresponding to the user-selected structure. 
         [0058]    As depicted, in certain embodiments, the search results screen  400  includes information buttons  410  that the user may select to obtain additional, detailed information about the methods  402 , run properties  404 , or structures properties  408 . In one embodiment, each information button  410  is associated with a row in the tabulated search results. For example, referring to  FIG. 5 , by selecting an information button  410  associated with a method in a row, the system  100  displays a method details screen  500  that includes detailed information about the method, such as the temperature and flow rate. Likewise, referring to  FIG. 6 , when an information button  410  associated with a structure is selected, the system  100  displays a structure details screen  600  that includes detailed information about the structure, including the name, weight, and molar volume. Further, referring to  FIG. 7 , when the user selects an information button  410  associated with a run, the system  100  displays a run details screen  700  that includes information about the run, including the sample name, date, and injection volume. In certain embodiments, the information displayed in  FIGS. 5-7  can be viewed simultaneously so that the user can compare and contrast the differences of the individual runs, molecules, and/or methods from the plurality of choices resultant from the query. 
         [0059]      FIGS. 8 and 9  depict a structure search screen  800  and a search results screen  900 , respectively, associated with a search for methods that separate two or more structures, in accordance with one embodiment of the present invention. As depicted in  FIG. 8 , the user has drawn a first chemical structure  802  and a second chemical structure  804 , using the structure buttons  302  and element buttons  304 . The user has also selected the third radio button  314  to indicate that a search for methods that separate the two structures  802 ,  804  is desired. The results from the search are displayed in the search results screen  900  of  FIG. 9 . As depicted, the search results include methods  902  that may be used to separate the two structures. The search results also indicate method properties, run details  904 , and structure properties  906 , associated with the two structures  802 ,  804 . 
         [0060]    In certain embodiments, the system  100  identifies methods that separate two or more structures by identifying methods that were previously successful for separating each structure on its own. The system  100  then compares the method properties and run details for these previous methods and identifies a preferred method that includes method properties and run details that are common to each of the previous methods. For example, if a previous method for separating a first structure included a temperature range of 100° C. to 200° C., and a previous method for separating a second structure included a temperature range of 150° C. to 250° C., then the preferred method may include a temperature range of 150° C. to 200° C. (i.e., the region of overlap between the two previous temperature ranges). 
         [0061]    In another embodiment, the system  100  archives search criteria and search results for later access by one or more users. For example, the system  100  may store, in the relational database  110 , the method properties, run details, structure properties, and search results associated with a particular search. When a user wants to perform the same or similar search at a later date, the search parameters and/or search results may be retrieved before the additional search is conducted. 
         [0062]    Accordingly, it can readily be seen that embodiments of the present invention provide a robust and powerful search application that, for example, facilitates the identification of appropriate methodologies for separating mixtures of compounds, deconvolving degradation products, and/or validating product specifications. 
         [0063]    It should also be noted that embodiments of the present invention may be provided as one or more computer-readable programs embodied on or in one or more articles of manufacture. The article of manufacture may be any suitable hardware apparatus, such as, for example, a floppy disk, a hard disk, a CD ROM, a CD-RW, a CD-R, a DVD ROM, a DVD-RW, a DVD-R, a flash memory card, a PROM, a RAM, a ROM, or a magnetic tape. In general, the computer-readable programs may be implemented in any programming language. Some examples of languages that may be used include C, C++, or JAVA. The software programs may be further translated into machine language or virtual machine instructions and stored in a program file in that form. The program file may then be stored on or in one or more of the articles of manufacture. 
         [0064]    Certain embodiments of the present invention were described above. It is, however, expressly noted that the present invention is not limited to those embodiments, but rather the intention is that additions and modifications to what was expressly described herein are also included within the scope of the invention. Moreover, it is to be understood that the features of the various embodiments described herein were not mutually exclusive and can exist in various combinations and permutations, even if such combinations or permutations were not made express herein, without departing from the spirit and scope of the invention. In fact, variations, modifications, and other implementations of what was described herein will occur to those of ordinary skill in the art without departing from the spirit and the scope of the invention. As such, the invention is not to be defined only by the preceding illustrative description.