Agilent G9250AA Pesticides and Environmental Pollutants Database

Transcription

1 Agilent G9250AA Pesticides and Environmental Pollutants Database Read Me Introduction 1 Overview 2 Compounds in the Database 4 Analytical Methods 4 VLOOKUP Function in Excel 5 Excel Shortcut Key Strokes 7 What Can I Do With the Database 7 Introduction Pesticide residue analysis is a complex task requiring the analyst to search for dozens, or even hundreds, of compounds in a wide variety of food matrices. GC/MS Tandem Quad (GC/QQQ) provides excellent sensitivity and selectivity in analyzing complex matrices, for example, food extracts. Agilent Technologies offers several pre-configured and pre-tested GC/QQQ Analyzers to simplify a lab s start-up process. The analytical capability of a lab, however, is largely determined by the completeness of the MS/MS transitions in an acquisition method. Agilent Technologies has developed an MS/MS MRM Pesticides and Environmental Pollutants Database of 1074 compounds to address many of the limitations most labs are facing. Key features of the MS/MS MRM Database: (file name: G9250AA_Database.xlsm) Allows users to build acquisition methods without buying all compound standards, thus saves time and money Includes retention times for either constant flow or constant pressure methods; corresponding RI (retention index) values are also included for easy migration to other GC oven programs Has multiple MS/MS transitions, average 8, for each compound which provides alternatives to work around matrix interferences Shows relative intensity of each MS/MS transition within a compound that facilitates transition selection Allows a quick-sort according to compound category (phthalates, PAHs, organophosphorus, fungicides, or semi-volatile pollutants etc.), CAS number, molecular formula, or molecular weight etc. Agilent Technologies

2 Overview The data acquisition method, based on your list of CAS numbers, can be easily created from a subset of MS/MS transitions in the Database. There are three videos on this DVD: a video that introduces the content and layout of the Database a video that guides you through building a MRM acquisition method based on your compound list a video that shows you how to add new compounds to the Database It is highly recommended that you watch the first two videos before reading the rest of this document! Watching the videos will help you understand the what and how to do with the database xlsm file. This MRM Database (file name: G9250AA_Database.xlsm) is in Microsoft Excel format for easy searching and filtering. Compounds are separated by color bands for clarity. The following basic compound information is included for each compound: Common Name Molecular Formula Molecular Weight (averaged) Molecular Weight (mono-isotopic) CAS #, without dashes for easy sorting Classification 1 Classification 2 Retention Times (RT) and Retention Indexes (RI) for Constant Flow and Constant Pressure methods (total 3 methods) Chinese Name and Japanese Name where available In addition, information is included for building MassHunter MRM acquisition methods: CAS #, standard format with dashes Common Name Method RT ISTD (true or false) Precursor Ion MS1 Resolution Product Ion MS2 Resolution 2 Read Me

3 Dwell Time Collision Energy (Voltage) RT Window Relative Intensity of each transition within a compound Read Me 3

4 Compounds in the Database Database Compounds Total Number Pesticides (fungicides, herbicides, insecticides, rodenticides and others) 675 Breakdown Products 42 Deuterated Compounds 6 Polybrominated Diphenyl Ether (PBDE) 4 Polybrominated Biphenyl (PBB) 1 Polychlorinated Biphenyl (PCB) 209 Polycyclic Aromatic Hydrocarbon (PAH) 26 Phthalates 17 Additional Semivolatile Pollutants 94 Analytical Methods A complete list of compounds can be found on the DB Compound List page (tab) of the Database. There are three sets of method parameters included in the Database: Constant Flow Screening Method - runtime 40.5 minutes, allowing more transitions than the shorter min method Constant Pressure Method (MS/MS Analyzer option 411) - runtime minutes Constant Flow Method (MS/MS Analyzer option 412) - runtime minutes All details for each method are listed on an individual page (tab) in the Database. It is advised to make a backup copy of the Database before using it. The retention times and retention index values corresponding to these three sets of methods are included for all compounds in the Database. Therefore, you can either use one of the above prescribed methods (RTs) or your existing lab method (RIs). The RTs can be a little off from the Database due to the different injection modes (LVI, split, or splitless) used. NOTE An RI to RT converter is included on the Database DVD so you can convert the RIs in the Database to expected RTs of your existing methods. 4 Read Me

5 VLOOKUP Function in Excel A very useful Excel function relevant to building a custom MassHunter acquisition method is VLOOKUP. This function helps you quickly pick out common entries between two lists (arrays). This function searches for a value in a column of a table (or array) and returns a value in the same row from another column in the same or different array. Show only my target compounds in the Database The following example shows how you can use the VLOOKUP function to pick out your list of compounds from a database. Your list of compounds is in Array A and the database is in Array B. Array A Column X Column Y Column Z Terbacil target Terbucarb target Terbufos target Terbumeton target Array B Column A Column B Column C Temephos =Vlookup( ) Terbacil Terbucarb Terbufos Terbumeton Terbuthylazine Terbuthylazine-desethyl Terbutryn Tetrachlorvinphos, E-isomer Tetraconazole Read Me 5

6 Using the VLOOKUP function in Column C to match CAS # between both arrays, you can easily pick out array A compounds in array B as the following: CAS # match result Column A Column B Column C Temephos #N/A Terbacil target Terbucarb target Terbufos target Terbumeton target Terbuthylazine #N/A Terbuthylazine-desethyl #N/A Terbutryn #N/A Tetrachlorvinphos, E-isomer #N/A Tetraconazole #N/A All the target tags, shown in Column C, represent array A compounds that are in array B. Lastly, use the filtering button on Column C to show only the target rows, i.e., hide or uncheck #N/A rows. The Database has a what is VLOOKUP tab to let you practice this function. How many of my target compounds are in the Database? When you want to find out if all your target compounds are in the Database, you can put the tag target in Column C and use VLOOKUP in Column Z to do the matching. NOTE Although the common name can be used in matching, variations in common names make it less certain to get an absolute match compared to using CAS numbers. 6 Read Me

7 Excel Shortcut Key Strokes These shortcuts help you use the Database more effectively and build an acquisition method easily. Quickly move to the end of a row or a column Press the End key followed by the down or up arrow key (for end of column) or left or right arrow key (for end of row). Select (highlight) multiple consecutive cells or multiple consecutive rows quickly Highlight the first row (or consecutive cells in a row), hold down the Shift key and press End and then down or up arrow key. Copy cell content down a column (Fill-Down) Click the to-be-copied cell (i.e., select the cell). Move the mouse pointer directly over the black square at the bottom right corner of the cell. As the pointer changes to a solid black + sign, double click. NOTE The copy-down operation only applies to cells that are adjacent to cells with content. What Can I Do With the Database How do I build a custom MassHunter acquisition method using the Database? The data acquisition method, based on your list of CAS numbers, can be easily created from a subset of MS/MS transitions in the Database. A video file that guides you through this process is included on this DVD. Two approaches to build an MRM method are described in the video: One uses Compound List Assistant (a MassHunter tool) for time segment overlap. The other uses Excel-based macro to set time segments and optimize dwell times. How do I add new compounds to the Database? Make a backup copy of the Database. A video file that guides you through adding compounds is included on this DVD. NOTE Due to MassHunter's requirement, no special characters or Greek letters are allowed in the Common Name column, for example, or Read Me 7

8 Agilent Technologies How do I find all nitrogen containing compounds in the Database? In cell AF2 (USER FIELD), type in =ISNUMBER(FIND("N",E2)). Do not copy and paste the text from this document into cell AF2, you must type it in yourself. Then, use the fill-down shortcut described above to apply this operation to all the rows in column AF. Lastly, use the filtering button on Column AF to show only the TRUE rows, i.e., hide or uncheck FALSE rows. How do I select all PCB congeners in the Database? Go to the Classification 2 column (column J) and click on the filtering button on the bottom right of cell J1. Uncheck the Select All box and scroll down the list to check the PCB box. Click OK. How do I select the 14 most toxic planar PCB congeners? Use the filter in column Q (User Field) and select only the Toxic Congener box. How do I use the RI values in the Database? The Database RIs were calculated using retention times of straight-chain hydrocarbons from C-8 to C-35. An RI_to_RT conversion tool is included on the Database DVD, so you can calculate expected retention times of your analytes based on the RIs in the Database and RTs of hydrocarbon markers (C-8 to C-35) from your existing GC method. If your existing method uses HP-5ms UI column of the same phase ratio as a 0.25 mm 0.25 m column, you will see the smallest difference between the expected and actual retention times for your analytes. More information is in the RI to RT conversion tool RI_to_RT_converter.xlsx. Warranty The material contained in this document is provided as is, and is subject to being changed, without notice, in future editions. Further, to the maximum extent permitted by applicable law, Agilent disclaims all warranties, either express or implied, with regard to this manual and any information contained herein, including but not limited to the implied warranties of merchantability and fitness for a particular purpose. Agilent shall not be liable for errors or for incidental or consequential damages in connection with the furnishing, use, or performance of this document or of any information contained herein. Should Agilent and the user have a separate written agreement with warranty terms covering the material in this document that conflict with these terms, the warranty terms in the separate agreement shall control. Agilent Technologies, Inc Printed in USA November 2011 Agilent Technologies, Inc Centerville Road Wilmington, DE