CFS - GLFC / STANDARD OPERATING PROCEDURE
Preparation of Solutions
SOP Number: M52506/034/001
TITLE: Preparation of Solutions
APPROVING OFFICIALS:
DD / MM / YY
Approved By:______Management___/___/___
Concurred By:______QAU Manager___/___/___
Prepared By:______/___/___
1.0Introduction
1.1Purpose
To assure reproducibility in preparation of solutions as well as adequacy and consistency of documented calculations associated therewith.
1.2Scope
This general-use technical SOP is a GLFC management directive that shall be followed for all projects/studies of Natural Resources Canada, CFS-GLFC, which prepare solutions in the conduct of GLP compliant studies.
1.3Definitions
Archivist - The person specified by management who is responsible for the management of the archive(s).
CFS-GLFC – Canadian Forest Service – Great Lakes Forestry Centre.
Document Control Official (DCO) - The person specified by management who is responsible for controlling designated documents, including SOPs.
Effective Date- The date from which the procedures given in a SOP are to be implemented.
Good Laboratory Practice (GLP)– A quality management system set forth by the Organization for Economic Cooperation and Development (OECD) to assure the quality and integrity of the processes and conditions under which non-clinical health and environmental safety studies are planned, performed, monitored, recorded, archived and reported.
Material Safety Data Sheet (MSDS)– a summary description of a chemical, reagent or substance prepared by the manufacturer or supplier which is required by WHMIS legislation to inform workers about procedures required to safely work the material.
NA- Not Applicable.
Quality Assurance Unit (QAU)- Persons designated by management to ascertain that the study is in compliance with current OECD Principles of Good Laboratory Practice, and who are completely independent from the conduct of the study for which they are performing quality assurance functions.
Reference item – Any item used to provide a basis for comparison with the test item.
Standard Operating Procedures (SOPs)- Management directives describing administrative or technical routine procedures conducted in a laboratory or field operation that are not specified in detail in the study plan or test guidelines.
Study Director– The individual responsible for the overall conduct of the non-clinical health and environmental safety study.
Study Plan– A document that defines the objectives and experimental design for the conduct of the study, and includes any amendments.
Test Facility Management– The individual who has the authority and formal responsibility for the organization and functioning of the test facility according to current OECD Principles of Good Laboratory Practice.
Test Material – An article which is the subject of a study, typically an analytical grade, technical grade or formulated product which is uniquely identified and characterized and which is tested in GLP compliant studies to examine its properties, human and/or environmental safety.
Workplace Hazardous Materials Information System (WHMIS)– a national information delivery system used to inform employees about hazardous materials in the workplace.
1.4Safety
1.4.1 Persons using solvents or other hazardous materials, must use minimum personal protective equipment as stipulated in the current version of SOP No. M52506/014, The Use ofPersonal Protective Equipment.
1.4.2 Persons using any solvents, chemicals, reagents or other hazardous materials must do so in accordance with the current version of SOP No. M52506/015 The Safe Handling of Hazardous Materials and pertinent MSDS sheets, which are stored on a shelf in the laboratory and in accordance with WHMIS labels.
1.4.3 Decanting, transfer or other handling of large (>500 mL) containers of solvents must be conducted in an approved operational fume hood. Fume hoods should be approved or certified annually.
1.4.4 All persons must receive WHMIS training and be familiar with emergency procedures as described in the CFS-GLFC Emergency and Fire Safety Manual, prior to working in a laboratory using hazardous materials. WHMIS and emergency procedure training as well as records associated therewith are to be coordinated by the CFS-GLFC Safety Officer.
1.5Materials
The materials required to prepare solutions include:
1.5.1GLP Form No. 0082/001 (Appendix 1) as well as GLP forms No. 0083/001, 0084/001, 0085/001 and 0086/001 (Appendices 2-5) with sufficient open data rows for recording appropriate data and calculations pertaining to the solutions being prepared.
1.5.2At the discretion of the study leader or principal investigator, a logbook for Preparation of Solutions and Serial Dilutions may be prepared to compile and retain exact copies of all forms associated with preparation off solutions. However, all original forms are considered raw data and must be retained together with the study records.
1.5.3Selected solvent(s).
1.5.4Appropriately sized glassware and hardware (e.g. volumetric flasks, spatulas, pipettes, and weighing vessels), as required for preparation of solutions involving either solid or liquid solutes.
1.5.5All glassware used in preparation of solutions required for pesticide residue analysis are to be cleaned in accordance with the current version of SOP M52506/008.
1.5.6Where micropipettes are to be employed, these must be certified, maintained, calibrated and operated in accordance with the current version of SOP M52506/018.
1.5.7All glassware is to be pre-labeled in accordance with the current version of SOP RS9701/001 and as mandated by WHMIS legislative requirements.
1.5.8Certified and calibrated top loading balance or analytical balance, used and maintained in accordance with the current version of SOP M52506/013 or M52506/017 respectively.
1.5.9Vortex mixer, inert stirring instrument, magnetic stir bar and retrieval rod and magnetic stir plate or hot plate maintained and used in accordance with the current version of SOP M52506/022 as required to ensure full dissolution of solutes and homogeneity of solutions.
1.5.10Indelible labels.
1.5.11WHMIS labels.
2.0PROCEDURES
2.1General Procedures
2.1.1Determine the type of solution and total volume required by reference to the study plan or pertinent test method.
2.1.2Follow required safety precautions for the specific solutes and solvents being used by referring to the appropriate MSDS sheets, and as set forth in the current version of SOP No. M52506/015, The Safe Handling of Hazardous Materials and SOP No. M52506/014, The Use of Personal Protective Equipment.
2.1.3Prepare WHMIS compliant or indelible labels for each solution to be prepared and affix to the container to be used for longer term or temporary storage of the final solution respectively. Choice of the type and size of the container to be used for final solutions will depend upon the volume of solution required and its subsequent use pattern. However, care should be taken to ensure that thecontainer material is inert to the solution components and that it is clean. Choice of container type will depend upon the volatility of the solute and solvent (influencing the type of closure required) and subsequent use for the solution (e.g. requirement for immediate use and decanting of measured portions may lead to use of a graduated cylinder; whereas requirement for longer term storage under refrigerated conditions may lead to use of a glass-stoppered Erlenmeyer flask).
2.1.4Use liquid measuring devices appropriate for the task (e.g. graduated cylinder, graduated pipette, volumetric flask, volumetric pipette etc.). Choice of appropriate devices will depend upon the volume to be delivered and the overall accuracy and precision of measured volumes required. As a general rule of thumb the total volume of the measuring device should not be greater than ten times that of the volume to be measured and delivered. Generally, for preparation of routine solutions standard graduated devices may be employed, whereas for solutions of reference and test materials or those requiring high levels of accuracy should typically involve the use of volumetric glassware and/or positive displacement micropipettes.
2.1.5Solvents and liquid solutes must be brought to ambient laboratory temperature prior to volume measurement or use.
2.1.6The exact amounts of the solutes and solvents required for each solution must be calculated and recorded using version 001 of GLP forms 0083 through 0086 (Appendices 2-5) depending upon the method used to prepare the solution (refer to section 2.6).
2.1.7All final solutions must be indelibly labeled with a minimum set of information including: chemical name, concentration, solvent, date prepared, initials of person preparing the solution and the expiry date if applicable.
2.1.8Do not return any unused solvent or chemical compound to the original container. Store in an appropriate container, pre-labeled according to WHMIS requirements, or discard it as set forth in the current version of SOP No. M52506/006, Disposal of Hazardous Waste.
2.1.9Documenting and handling of original and exact copies of solution preparation documents must be performed as described in section 2.6.
2.1.10For solutions which constitute samples, test materials or reference items, documentation of their creation or subsequent use must be made in accordance with the current version of SOP M52506/025.
2.2Preparation of Solutions Involving Solid Solutes and Mass Measurements:
2.2.1Choose the appropriate type of balance for weighing out the solid solute. Choice of balance type will depend upon the mass and accuracy required for the specific solution. General-use solutions may be prepared using a top loading balance. Solutions requiring a higher degree of accuracy or which are being used as reference items or test materials should be prepared using an analytical balance unless logistically infeasible owing to large mass requirements.
2.2.2With appropriate compensation for the purity of the substance being weighed, calculate the required mass of solute and volume of solvent required to make the desired solution and record calculations on GLP Form No. 0083/001.
2.2.3Ensure the balance has been appropriately calibrated and use it to tare a clean, appropriately-sized weighing vessel, such that a stable zero reading is obtained.
2.2.4Using a clean spatula or similar instrument, carefully transfer the required amount of the solid solute into the weighing vessel, ensuring that no spilled material is left on the balance pan or on the outside of the vessel.
2.2.5Quantitatively transfer the solute mass from the weighing vessel into the final solution container. Add aliquots of solvent to rinse the weighing vessel and transfer rinsates into the final solution container to ensure quantitative transfer.
2.2.6Add the majority of the required volume of the solvent to the final solution container and mix the solution apparatus such that the solute is fully dissolved and the solution is visibly homogeneous. In cases where full dissolution of the solute may require heating or extensive mixing, use of a temperature-controlled, magnetic, hotplate/stirrer apparatus is recommended. Where no heating or only minimal mixing is required dissolution and homogeneity may be achieved by hand-swirling, vortex-mixing, stirring with an inert instrument or by repetitive inversion.
2.2.7Bring the solution to its required final volume by further addition of the solvent and remix the complete solution to ensure complete homogeneity. If a magnetic stir bar has been employed in mixing remove it using a Teflon coated magnetic retrieval rod.
2.3Preparation of Solutions from Liquid Solutes Using Mass Measurement:
2.3.1Ensuring that appropriate adjustment is made for purity, calculate the required mass of the liquid solute required and record the calculations on GLP Form No. 0083 /001.
2.3.2Calibrate the balance chosen for this task and use it to tare a clean, appropriately-sized weighing vessel, such that a stable zero reading is obtained.
2.3.3Using a clean, inert device (e.g. pipette, cylinder, beaker) transfer the required amount of the liquid solute into an appropriate sized weighing vessel, ensuring that no spilled material is left on the balance pan or on the outside of the vessel.
2.3.4Quantitatively transfer the weighed out solute into the final solution container and use aliquots of the solvent to rinse the weighing vessel with rinsates added into the final solution container.
2.3.5Add the majority portion of the solvent to the final solution container. In cases where full dissolution of the solute may require heating or extensive mixing, use of a temperature-controlled, magnetic, hotplate/stirrer apparatus is recommended. Where no heating or only minimal mixing is required dissolution and homogeneity may be achieved by hand-swirling, vortex-mixing, stirring with an inert instrument or by repetitive inversion.
2.3.6Bring the solution to final volume by further addition of the solvent and remix the complete solution. If a magnetic stir bar has been employed remove it using a Teflon coated magnetic retrieval rod.
2.4Preparation of Solutions from Liquid Solutes by Volume Measurement:
2.4.1Following the example provided in the top line of GLP Form No. 0084/001, and with reference to section 2.5 of this SOP, determine and record the appropriate solvents and respective volumes required for the solution being prepared.
2.4.2Using a clean, inert, measuring device of appropriate volume and accuracy, measure out the required volumes of each liquid comprising the final solution.
2.4.3Transfer the measured volume(s) of each of the liquid solutes into the final solution container. In most cases involving liquid solutes only minimal mixing is required to ensure complete dissolution and homogeneity. This may generally be achieved by hand-swirling, vortex-mixing, stirring with an inert instrument or by repetitive inversion.Ensure the solution is visibly homogeneous prior to use.
2.5Calculations
2.5.1Significant Digits and Rounding
(a) All measurements/calculations will be taken to the number of
decimal places required as stipulated in the study plan.
(b) All numbers will be rounded.
(c) Rounding will be determined by the subsequent digit.
Example: If rounding to 2 decimal places:
If the number in the third decimal place is 5 or greater, the number preceding it will increase by one, whereas if the number in the third decimal place is less than 5, the number preceding it will remain the same.
Example:
236.548 will be rounded up to 236.55 whereas 236.543
will be rounded to 236.54
2.5.2 Calculations for Preparation of a Solution Using a Weight:Volume Approach
Follow the example on GLP Form No. 0083/001.
2.5.3Calculations for Preparation of a Solution Using Volume Measurements and Ratio Notation
Follow the example on GLP Form No. 0084/001.
Note that there are two common notation methods used in preparing and documenting solutions, however they are often mistakenly applied. For consistency and compliance with this SOP ratio notation must be used, following the example line as shown on GLP Form No. 0084/001. Using ratio notation a 1:10 solution of ethanol and water (read and pronounced as a 1 to 10 solution of ethanol and water). With this notation, the total number of parts of the solution being the sum of the numbers (in this case is 1+10=11. Thus 1:10 represents an 11 part solution of which 1 part is ethanol (the solute) and 10 parts are water.
2.5.4Calculations for Preparation of a Solution Using Volume Measurements and Percent Notation
Follow the example on GLP Form No. 0085/001.
2.5.5Calculations for Preparation of Molar Solutions
Follow the example on GLP Form No. 0086/001.
2.6Documentation and Reporting
2.6.1.Any solutions prepared must be recorded on GLP Form No. 0082/001 (Appendix 1). The original is to be maintained with the study records and a copy may be maintained in the logbook for Preparation of Solutions and Serial Dilutions. If the solution is a test material or reference item, refer to section 2.6.3.
2.6.2.Calculations for preparation of any solution must be documented on version 001 of the applicable form (i.e. one of GLP Forms numbered 0083 through 0086 (Appendices 2-5) depending upon methods used). The original of each form is to be maintained with the study records. Exact copies may be compiled in a separate logbook for solutions if desired.
2.6.3.In the case where the solution being prepared is a test material or reference item, an exact copy of the record of solutions prepared and associated forms for calculations for that solution must be filed in the Test Materials and Reference Items Logbook.
3.0DisTRIBUTION AND ARCHIVING
3.1distribution
3.1.1Official copies of this SOP shall be made by the DCO and distributed as follows:
(a)The original SOP and an exact copy shall be retained in the GLFC archive (i.e., copies 001 and 002).
(b)One copy shall be kept by the DCO in the DCO SOP manual (i.e., copy 003).
(c)One copy shall be kept by the QAU manager in the QAU manager SOP manual (i.e., copy 004).
3.1.2The DCO may distribute additional copies of this SOP to personnel engaged in the supervision or conduct of GLP studies.
3.1.3The DCO shall announce the availability of new versions of this SOP within one week of the effective date, and shall distribute new versions by requiring that old versions be exchanged for the new ones.
3.2Archiving
The Archivist shall maintain current and historical versions of this SOP.
3.3Destruction of Outdated SOPs
With the exception of archived historical versions, the DCO shall ensure the destruction of outdated versions of this SOP by shredding.
4.0ASSURING SOP VALIDATION AND COMPLIANCE
4.1SOP Validation
The QAU is responsible for assuring that this SOP is valid.
4.2SOP Compliance
The Study Director is responsible for assuring that this SOP is followed.
5.0REVISION of the sop
5.1Responsible Individual
The QAU is responsible for assuring that this SOP is current. If necessary, the QAU manager shall initiate the revision process.
5.2Revision Schedule
5.2.1This SOP shall be revised when its provisions no longer agree with current practices or applicable regulations.
5.2.2If this SOP requires revision, it shall be revised according to current GLFC procedures and approved within 45 calendar days of initiation of the revision process.
6.0cONTINGENCIES
When personnel find circumstances that do not permit compliance with this SOP, they shall consult both the QAU manager and the Study Director.
7.0cONFIDENTIALITY
All SOPs are considered confidential and shall be handled accordingly. They are not to be copied or made available to outside parties without proper safeguards and the approval of management. Distribution to outside parties shall be conducted by the DCO.
8.0References
(a) CFS-GLFC Emergency and Fire Manual
(b) SOP No. M52506/014, The Use of Personal Protective Equipment
(c) SOP No. M52506/015, The Safe Handling of Hazardous Materials
(d) SOP No. M52506/013, Maintenance, Calibration and Operation of Electronic Top Loading Balances.
(e) SOP No. M52506/017, Maintenance, Calibration and Operation of Analytical Balances.
(f) SOP No. M52506/006, Disposal of Hazardous Waste.
(g) SOP No. RS9701/001, General Laboratory Procedures
(h) SOP No. M52506/008, Routine Cleaning of Laboratory Glassware and Hardware