Ensuring pipette & weighing device performance: Verification & Calibration

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1 Ensuring pipette & weighing device performance: Verification & Calibration Wan Melissa Diyana bt Wan Normazlan Central Research Laboratories, Faculty of Medicine

2 terms What is preventive maintenance? Regularly performed on a piece of equipment to lessen the likelihood of it failing. What is calibration? The process of comparing the unknown with a reference standard and reporting the results.

3 Agenda : PIPETTE VERIFICATION AND CALIBRATION Pipette maintenance & calibration Correct pipetting techniques Type of pipettes

4 Pipette Working Principles & Type Syringe Serological pipette Positive displacement

5 Pipette Working Principles & Type Air displacement Single Channel Pipette Multi Channel Pipette Stepper Multistepper

6 Agenda : PIPETTE VERIFICATION AND CALIBRATION Pipette calibration Pipette preventive maintenance Pipette Types

7 Pipette Maintenance Cleaning Procedures Clean the outer surface with alcohol wipes Dissemble lower part Rinse with suitable cleaning agent Lubricate piston / cylinder with suitable grease Allow to dry (max 60 C / air dry) Rinse well with DI water Assemble pipette

8 Pipette Maintenance Cleaning Procedures CONTAMINANT Aqueous solutions Organic solvents / Proteins Infectious liquid & Cell cultures Nucleic Acid Radioactive substances CLEANING AGENT Distilled water Diluted with mild detergant 70% Ethanol / IPA DNA/RNA decontimination Radioactive cleaning agent

9 Basic Pipette Maintenance Setting the micrometer Leak test Storing the pipettes Approach each volume in the same direction each time Turn micrometer 1/3 revolution above desired volume Dial down to volume setting Hold pipette with tips containing water in 90 angle. Observed any leaking occur. Store the pipette with the micrometer set at the nominal (maximum) volume

10 Agenda : PIPETTE VERIFICATION AND CALIBRATION Pipette calibration Pipette preventive maintenance Pipette Types

11 Importance of Pipette Calibration & How it is done?

12 Importance of Pipette Calibration Calibration : set of operations that establish the relationship between the dispensed volume and the selected volume of the apparatus. Liquid transfer in µl range error as small as 1 µl matters Pipette is the main item in the laboratory. Audit requirement

13 Pipette Calibration Pipette calibration according to Specifies the requirements for accurate and reliable calibration of piston-operated volumetric apparatus (pipette, burettes etc.) Test method, equipment, test conditions, error limits, reporting requirements. GRAVIMETRIC METHOD involves weighing device

14 Pipette Calibration Setup CALIBRATION SOFTWARE PIPETTE & TIPS TRAINED AND COMPETENT CALIBRATOR THERMOMETER ANALYTICAL BALANCE STRICTLY CONTROLLED ENVIRONMENTAL CONDITION

15 Pipette Calibration Setup Balance of sufficient resolution for the selected volume of test pipette. Ensures deviations are recorded exactly for assessment *use the pipette nominal volume to select the balance

16 Micropipette volume range 20ul 50ul Pipette Calibration Setup

17 Pipette Calibration Setup Weighing vessel Draft shield Evaporation Trap (for volume <50 ul)

18 Pipette Calibration Setup Test Liquid Distilled or deionized water conforming to grade 3 of ISO 3696 Equilibrated with surrounding air Temperature should be the same as room temperature

19 Pipette Calibration Setup environmental condition Draft free Relative Humidity above 50% Temperature between 15 C to 30 C (± 0.5 C)

20 Pipette Calibration Setup Test volume Fixed volume pipette Nominal volume 10 measurements Variable-volume pipette Nominal volume 10 measurements 50 % of nominal volume 10 measurements Lower limit of useful volume range, or 10% of nominal volume, whichever is greater 10 measurements Total 30 measurements

21 Pipette Calibration Setup Test volume Multi-channel pipettes Each channel is regarded as a single channel and tested and reported as such. 8 channel = 30 x 8 = 240 measurements 12 channel = 30 x 12 = 360 measurements

22 Pipette Calibration Setup Pipette Tips Pipette and tips are calibrated as 1 system Dispensing system = pipette + tip

23 Pipette Calibration Certificate

24 Agenda : WEIGHING DEVICE VERIFICATION AND CALIBRATION Weighing device calibration Preventive Maintenance of weighing balance Type of balances

25 Weighing Device Types Mechanical Equal-arm Beam Balances Single pan Electronic Balances Mechanical Single Pan Balances

26 Agenda : WEIGHING DEVICE VERIFICATION AND CALIBRATION Weighing device calibration Preventive Maintenance of weighing balance Type of balances

27 Weighing the right way Window free, no direct sunlight Do not place the balance in the air flow Light and Air Keep the temperature of the room as constant as possible. Ideally, the relative humidity (% RH) should be between 45 and 60 % Weighing Bench LOCATION OF THE BALANCE Temperature and Humidity Stable Anti magnetic Protected against electrostatic charges Wall or floor installation Work Room Vibration free Free from drafts

28 Weighing device maintenance Never switch off your balance Align the balance (leveling) Cleaning of the balance External weight standard check

29 Agenda : WEIGHING DEVICE VERIFICATION AND CALIBRATION Weighing device calibration Preventive Maintenance of weighing balance Type of balances

30 Weighing Device Calibration Setup WEIGHING BALANCE TRAINED AND COMPETENT CALIBRATOR CALIBRATED STANDARD WEIGHT STANDARD CONTROLLED ENVIRONMENTAL CONDITION PORTABLE HYGROMETER STABLE WEIGHING BENCH

31 Weighing Device Calibration Method Material & apparatus Reporting

32 Weighing Device Calibration Certificate

33 FOMCAL services Single channel micropipette Calibration RM 50 / pipette Validation / Intermediate Check RM 20 / pipette Multi channel micropipette Calibration RM 100 / pipette - 8 channels RM 120 / pipette - 12 channels Validation Intermediate Check RM 50 / pipette - 8 channels RM 120 / pipette - 12 channels

34 FOMCAL services Calibration Validation / Intermediate Check RM 120 / device RM 50 / device Maximum capacity = 200 g

35 FOMCAL team Wan Melissa Diyana Mohamad Zulkefly Sharifah Nurzuraini Mazwan Jamalluddin Nur Liyana

36 FOMCAL services Block B, 4 th Floor, Faculty of Medicine University of Malaya fomcal@um.edu.my

37 PERSATUAN JURUTEKNOLOGIS MAKMAL UNIVERSITI MALAYA, (PJMUM) PERSATUAN PEGAWAI SAINS UNIVERSITI MALAYA, (SOUM) FAKULTI PERUBATAN UNIVERSITI MALAYA (FOM) CENTRAL RESEARCH LABORATORIES (CRL)