Liquid Handling
Application Notebook
Tips on how to
pipette
Page 1: ...Liquid Handling Application Notebook Tips on how to pipette...
Page 2: ...2...
Page 3: ...5 Troubleshooting 16 Calibrating your pipettes 17 Formulas for calculating results 21 Conversion tables 23 Ensuring optimum performance 24 Factors affecting the accuracy of air displacement pipettes 2...
Page 4: ...iston that moves in a cylinder or in a capillary In air displacement pipettes a certain volume of air remains between the piston and the liquid In positive displacement pipetting the piston is in dire...
Page 5: ...lume of air as indicated on the volume setting 3 After immersing the tip into the liquid the operating button is released This creates a partial vacuum and the specified volume of liquid is aspirated...
Page 6: ...npipette Stepper Finnpipette PDP Finntips for positive displacement pipetting Finntip Stepper Finntip PDP How does a positive displacement pipette work 1 The piston moves to the appropriate position w...
Page 7: ...d not be cleaned for reuse as their metrological characteristics will no longer be reliable Pre rinsing three five times the tip with the liquid to be pipetted improves accuracy especially when using...
Page 8: ...dispensing small volumes Reverse pipetting is only possible with air displacement pipettes 1 Press the operating button to the second stop 2 Dip the tip into the solution to a depth of 1 cm and slowl...
Page 9: ...forward technique steps 1 and 2 to fill the tip with blood do not prerinse the tip Wipe the tip carefully with a dry clean cloth 1 Dip the tip into the blood and press the operating button to the fir...
Page 10: ...tive displacement Air displacement Air displacement Positive displacement Air displacement Positive displacement Air displacement Positive displacement Tip Standard Standard or wide orifice Positive d...
Page 11: ...pipette and a standard or wide orifice tip Technique Use the whole blood pipetting technique Reverse pipetting should be used if high accuracy is needed Notice Residual serum can sometimes be found on...
Page 12: ...n side the tip Aspiration and dispensing should be done slowly The use of a posi tive displacement pipette and tip is also advisable for pipetting Tween 20 Bronidox L 10 preservative Pipette tip combi...
Page 13: ...luoroacetic acid Do the pipetting quite rapidly to minimise vapour formation Nucleic acids DNA RNA solutions Pipette tip combination Choose an air displacement pipette and a filter tip or a positive d...
Page 14: ...cause contamination of samples Prevention Use sterilised tips or sterilised filter tips and if possible autoclave the pipette Change the tip after pipetting of each sample Sample to pipette Samples or...
Page 15: ...he pipette DNA test DNA aerosols with sample concentrations of 20 50 and 100 g l 1 were blown onto the filters Finntip Filters prevented DNA aerosol of these concentrations coming through filter into...
Page 16: ...ing with gloves Finnpipette BioControl Problem Possible cause Solution Leakage Tip incorrectly attached Attach tips firmly Foreign bodies between Clean and grease 0 ring and tip cone the piston 0 ring...
Page 17: ...standards Calibration of Pipettes in a Quality System The main objective of pipette calibration in a quality system is to ensure that meas urements are made with the intended accuracy Very often error...
Page 18: ...ature A new tip should be pre wetted 3 to 5 times to improve the accuracy Always pipette water from a reservoir do not take it back from the balance Check the calibration regularly depending on the fr...
Page 19: ...ioControl calibration software A series of ten pipettings is performed with both volumes Calculate the accuracy and precision of both series using the formulas below and compare to the limits given in...
Page 20: ...followed by the PK factor Note These factors have different values depending on the module so please check that you choose the right module 5 Enter these factors to the OLD FACTORS fields of the calib...
Page 21: ...weight mg e evaporation loss mg Z conversion factor for mg l conversion Note Evaporation loss can be significant with low volumes To determine mass loss dis pense water into the weighing vessel note...
Page 22: ...t according to the DIN 12650 standard for single chan nel air displacement pipettes For multichannel pipettes these limits are doubled With variable volume pipettes the nominal volume is the maximum v...
Page 23: ...023 1 0023 1 0024 1 0024 18 1 0022 1 0023 1 0024 1 0024 1 0025 1 0025 18 5 1 0023 1 0024 1 0025 1 0025 1 0026 1 0026 19 1 0024 1 0025 1 0025 1 0026 1 0027 1 0027 19 5 1 0025 1 0026 1 0026 1 0027 1 002...
Page 24: ...ate but not precise The mean volume is the correct set volume but separate pipettings differ from the set volume Precise but not accurate There is no variation between the separate pipet tings but the...
Page 25: ...p immersed about 1 cm into the liquid 2 Pipette vertical tip immersed about 3 cm into the liquid 3 Pipette at a 30 40 angle tip immersed about 3 4 cm into the liquid Finnpipette 1 0 0 Fi nn pi pe tte...
Page 26: ...furic acid H2 SO4 1 85 kg dm3 Altitude The geographic altitude affects the accuracy through the air pressure The air pres sure decreases at higher altitudes and the conversion factor Z decreases as we...
Page 27: ...cleaned parts with the silicon grease that comes with the pipette 5 Assemble the pipette Note The calibration has to be checked after cleaning the pipette see page 17 for the calibration check procedu...
Page 28: ...l bath overnight Autoclave the Finnpipette Digital in one piece at 121 C for 20 min Viruses and spores can be inactivated by wiping the the pipette with a tissue moistened with 5 sodium hypochlorite M...
Page 29: ...Poor Poor Formicacidconcentrate Good Good Good Poor Fair Lacticacid Good Good Good Good Maleicacid Good Good Good Good Palmiticacid Good Good Good Good Salicylicacid Good Good Good Good Tannicacid Goo...
Page 30: ...enol Phenol Fair Good Good Poor Poor Salt inorganic Aluminium chloride Good Good Good Poor Fair Aluminium fluoride Good Good Good Poor Ammonium carbonate Good Good Good Good Fair Barium chloride Good...
Page 31: ...on How many times I can pipette on a full battery without recharging it Answer It depends on the module you are using With the 8 channel module 50 300 l you can pipette at least 500 times Question How...
Page 32: ...absytems at http www labsystems fi contact htm Question What is the filter pore size of Finntip Filter tips Answer The average pore size is 18 35 m The pores however don t have a straight shape All po...
Page 33: ...ompound It is recommend using positive displace ment pipettes for highly volatile compounds since the built in piston tip is in direct contact with the liquid Question How accurately can I pipette war...
Page 34: ...Working at the microscope Put your elbows on a special support and keep your wrist in its natural position Working at the laminar flow cabinet or chemical hood There should be free space for the legs...
Page 35: ...se lighter or electronic pipettes and dispensers Use tubes that can be opened and closed easily Finnpipette Warranty Policy Warranty policy 3 year warranty for all manual pipettes 1 year warranty for...
Page 36: ...hermo Labsystems Imageneering Agency Kirjapaino Lars Eriksen Oy 07 01 Sorvaajankatu 15 P O Box 208 FIN 00811 Helsinki Finland Tel 358 9 329 100 Fax 358 9 3291 0415 www labsystems fi A Thermo Electron...
