Lab Exam 1 review notes.docx - Lab 1 Back ground...

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Lab 1. Back ground information: -Accuracy and precision. Steps of using a Pipette: 1. Put on Pipette Tip 2. Press to 1 st stop 3. Insert into a solution 4. release the plunge 5. Press to 1 st stop then 2 nd stop. 6. Eject the tip Types: P20/200/1000 2-20 20-200 100-1000 uL Readings: 0 5 0 P20 5uL P200 50uL P1000 500uL Bradford assay: Bradford reagent binds protein, turns blue. Spectrophotometer, 595 nm Absorbance and transmittance, inversive. Blank, contains everything except what we are trying to measure. Compensate volume using buffer. Standard curve:
X-concentration y-absorbance y=ax+b Calculate Unknown: Unknown absorbance->y solve x -> final concentration. C1V1=C2V2 C2->x V2->final total volume C1->original concentration, V1->volume took. Unit conversion, include units in all your calculations. Example: Standard curve: y=0.0245x+0.0024 Unit of x -> ug/mL Absorbance = 0.34 Unknown Bradford NaCl 10 uL 900 uL 90 uL : final concentration: X=(y-0.0024)/0.0245 (ug/mL) =13.78 ug/mL Unknown concentration: =C2V2/V1= 13.78 ug/mL x 1 mL /10 uL= 1378 ug/mL Use of Spectrophotometer: 1. warm up 2. select wavelength