IgG Detection Using Anti- IgG Conjugated Microparticles

IgG Detection Using Anti-IgG Conjugated MicroparticlesBy Sarah Leung and Anbar Najam

Methods Conjugated anti-IgG antibodies to 0.92 um microparticles

33% microparticle surface coverage with IgG

0.02% microparticle concentration in solution

Methods Positioned a 180 degree optical reflection probe directly above samples for detection on a two-well slide

Results 5*10-11 g/mL to 5*10-6 g/mL IgG serial dilutions

Chart1

12781

13317.01

13434.23

13220.23

13609.68

12725.56

13262.83

Concentration (g/mL)

Intensity

Sheet1

Concentration (g/mL)IntensityAverage IntensityStandard DeviationT-TestHalf Standard Deviation

014343.2313823.9014397.2914188.14316.59707158.2985345005

013588.0115013.8115013.8114538.54823.186010.60546411.5930069053

014091.4413949.9114787.0014276.12448.061400.68306224.0307012629

013554.3913991.2813768.1613771.28218.461670.29406109.2308372592

014015.1813696.3713864.8613858.80159.491270.1062679.7456369234

014614.2314335.9714818.3214589.51242.123550.02932121.0617745546

0.000000000514202.5913778.8513541.3913840.94334.944840.30762167.4724205155

0.00000000514060.2713669.9314155.5613961.92257.320160.02712128.6600813189

0.0000000513859.6114368.3613688.4713972.15353.639620.63187176.8198087272

0.000000514525.5713819.2113730.6614025.15435.635070.59152217.8175326008

0.00000513982.3814030.3713884.6013965.7874.288700.4165337.1443475961

Sheet1

158.2985345005158.2985345005

411.5930069053411.5930069053

224.0307012629224.0307012629

109.2308372592109.2308372592

79.745636923479.7456369234

121.0617745546121.0617745546

167.4724205155167.4724205155

128.6600813189128.6600813189

176.8198087272176.8198087272

217.8175326008217.8175326008

37.144347596137.1443475961

Concentration (g/mL)

Intensity

Sheet2

Concentration (g/mL)

012781

013317.01

0.000000000513434.23

0.00000000513220.23

0.0000000513609.68

0.000000512725.56

0.00000513262.83

Sheet2

Concentration (g/mL)

Intensity

Sheet3

Results5*10-15 g/mL to 5*10-6 g/mL IgG serial dilutions

Chart2

14188.14158.2985345005158.2985345005

14538.5433333333411.5930069053411.5930069053

14276.1166666667224.0307012629224.0307012629

13771.2766666667109.2308372592109.2308372592

13858.803333333379.745636923479.7456369234

14589.5066666667121.0617745546121.0617745546

13840.9433333333167.4724205155167.4724205155

13961.92128.6600813189128.6600813189

13972.1466666667176.8198087272176.8198087272

14025.1466666667217.8175326008217.8175326008

13965.783333333337.144347596137.1443475961

Concentration (g/mL)

Intensity

Sheet1

Concentration (g/mL)IntensityAverage IntensityStandard DeviationT-TestHalf Standard Deviation

014343.2313823.9014397.2914188.14316.59707158.2985345005

013588.0115013.8115013.8114538.54823.186010.60546411.5930069053

014091.4413949.9114787.0014276.12448.061400.68306224.0307012629

013554.3913991.2813768.1613771.28218.461670.29406109.2308372592

014015.1813696.3713864.8613858.80159.491270.1062679.7456369234

014614.2314335.9714818.3214589.51242.123550.02932121.0617745546

0.000000000514202.5913778.8513541.3913840.94334.944840.30762167.4724205155

0.00000000514060.2713669.9314155.5613961.92257.320160.02712128.6600813189

0.0000000513859.6114368.3613688.4713972.15353.639620.63187176.8198087272

0.000000514525.5713819.2113730.6614025.15435.635070.59152217.8175326008

0.00000513982.3814030.3713884.6013965.7874.288700.4165337.1443475961

Sheet1

158.2985345005158.2985345005

411.5930069053411.5930069053

224.0307012629224.0307012629

109.2308372592109.2308372592

79.745636923479.7456369234

121.0617745546121.0617745546

167.4724205155167.4724205155

128.6600813189128.6600813189

176.8198087272176.8198087272

217.8175326008217.8175326008

37.144347596137.1443475961

Concentration (g/mL)

Intensity

Sheet2

Concentration (g/mL)

012781

013317.01

0.000000000513434.23

0.00000000513220.23

0.0000000513609.68

0.000000512725.56

0.00000513262.83

Sheet2

Concentration (g/mL)

Intensity

Sheet3

Discussion Results lacked evidence of any trends between antigen concentration and light scattering intensity Possible explanations:Coagulation of microparticlesHigh scattering due to 180 degree detectionConjugation of antibody, rather than antigen, to microparticles

Next Experiment Added TWEEN 80 to existing 0.92 um microparticle solution and evaluate 180 degree vs. 45 degree light scattering detection

180 degrees45 degreesVs.

Results5*10-14 g/mL to 5*10-6 g/mL IgG serial dilutions

Results5*10-14 g/mL to 5*10-6 g/mL IgG serial dilutions

Discussion 180 degree results lacked evidence of any trends between antigen concentration and light scattering intensity

With 45 degree probe, we found a detection limit of 10-6 g/ml

Contact Angle Measurements of Anti-E. Coli and Anti-E. Coli Conjugated Microparticles on Superhydrophobic Surface

Methods Conjugated anti-E. coli antibodies to 0.92 um microparticles

33% microparticle surface coverage with anti-E. coli

0.02% microparticle concentration in solution

Methods Dispensed 10 ul droplet on to superhydrophobic surface.

Measured contact angle over 10 minutes

Droplets:Deionized WaterAnti-E. coli -Conc. 5*10-7 Anti-E. coli conjugated to microparticles

ResultsAnti-E. coli -Conc. 5*10-7

Discussion Results oscillate and do not form a smooth curve.

Possible explanations:Surface contaminationDroplet movement, vibration.Position of droplet.Size of droplet

Next ExperimentDecrease the volume of the droplet from 10 ul to 3 ul for a more spherical shape.

Methods

ResultsDeionized Water

Future WorkMinimize the oscillations.

Change the position of the surface.

Determine an efficient way to dispense 3ul droplet on to superhydrophobic surface

AcknowledgementsUA/NASA Space Grant

Dr. Jeong-Yeol Yoon

Lab group: Tremaine B. Powell, Jin-Hee Han, Brian C. Heinze, Phat L. Tran, Jennine N. Chesler, Dr. Keesung Kim, and Dr. Song