PFP MB Creation

Primary Equipment:
15-660 Amplified Ultrasound Transducer
Created: February 23, 2010 by Tony Butterfield

Revised: August 16, 2010 by Tony Butterfield

University of Utah, Chemical Engineering

Latex Container Preparation:

  1. Wash latex glove finger with DI H2O 4 times.
  2. Fill latex glove finger with DI H2O.
  3. Clip to seal off and sonicate for 5 min in the UES 15-660.
    1. Amp = 5, Pulse = 10, Rep = 1, Freq = 5.5.
  4. Empty and repeat sonication with new water.
  5. Empty, rinse, and allow to dry before use.

MD Creation:

  1. Inject ml of filtered 0.25% PEG/PLLA into a prepared latex container.
  2. Leave open to air and placed in water at 42C (Temperature = 30 on Aquasonic 50D)
  3. Heat for 1 Hr to degas, sonicate for the last half hour.
  4. Seal liquid with clip, sure to keep any air from the liquid (this may mean sacrificing a small amount of liquid).
  5. Place in fridge for 15 min.
  6. With a cold pipette tip from the freezer, add ~wtp_pfp*vol*10~dv =wtp_pfp*vol*10 microliters PFP ( wt%) to surfactant solution. Do all this in the fridge to keep it cold (move pfp bottle to fridge).
  7. Seal the glove tip again with a clip, sure to keep air out, carful to not touch PFP drop.
  8. Sonicate the sample for 10 cycles with the UES 15-660, skipping every other cycle to keep from overheating the solution (20 cycles total).
    1. Amp = 2, Pulse = 10, Rep = 1, Freq = 5.5
  9. Solution should turn milky by 2nd cycle; be sure to sonicate all over the sample but particularly at the liq/vap boundary.
  10. Pour latex glove finger contents into 2 ml tube.
  11. Immediately take a sample, and characterize droplet size distribution and concentration.
    1. Dilute 1:5 with degassed surfactant solution.
    2. Inject 100 microleters of diluted md solution into one side of the hemocytometer.
    3. Inject 100 microleters of di water into the other side of the hemocytometer.
    4. Use the arc lamp and the 40X objective on the microscope (allow the arc lamp to warm up for about 10 min before use).
    5. Start the computer and open the Nikon camera software, Camera Control Pro.
    6. Set camera setting: Sutter Speed = 1/400 sec, Exposure Compensation = +4/3EV.
    7. Click Tools and then Download Options.
    8. Create an appropriate folder:
      1. Folder name: (each attribute separated by underscore)
      2. Experiment Date: ed=mm-dd-yy
      3. Sample Origin Date: so=mm-dd-yy
      4. Experiment type: ex=x (where x is P for pressure and/or T for temperature and/or t for time with no spaces)
      5. Operator: op=x (x is P for Praveena and T for Tony)
      6. MB Concentration: mc=x (where x is the fraction of concentration from original)
      7. Surfactant type: st=x (x is pg for peg-plla and ct for ctab)
      8. Surfactant concentration: sc=x (x in g/ml)
      9. PFP concentration: pc=x (x in ml/ml)
      10. Example folder: ed=01-01-10_so=12-30-09_ex=Pt_op=T_mc=0.5_st=pg_sc=0.25_pc=0.02
    9. Input an appropriate file name:
      1. Pressure: P=x (where x is pressure in guage inHg)
      2. Temperature: T=x (where x is temperature in C)
      3. Focus: F=x (where x is d for focus on droplets, and b for focus on bubbles)
      4. Filename ends in number assigned by camera software (time will be taken from file data)
      5. example file: P=-10_T=25_F=b.jpg
    10. Focuse the microscope so that the droplets are in sharp focus and take at least 10 images.
    11. Take 2 or 3 images of the DI water to be used as control images to subtract out lens imperfections (These file names should begin with CONTROL).
    12. Run the matlab program md_datasets and then md_analysis to get droplet concentration and size distribution.