1. Quantum dot-based lab-on-a-bead system for multiplexed detection of free and total prostate-specific antigens in clinical human serum samples 
Kristina Brazhnik, MS, Zinaida Sokolova, MD, PhD, Maria Baryshnikova, PhD, Regina Bilan, MS, Anton Efimov, PhD, Igor Nabiev, PhD, DSci, Alyona Sukhanova, MD, PhD 
Nanomedicine: Nanotechnology, Biology and Medicine 
Volume 11, Issue 5, Pages (July 2015)
DOI: /j.nano
Copyright © 2015 Elsevier Inc. Terms and Conditions

2. Figure 1 QD-encoded microbeads for multiplexed cancer diagnosis.
Panels A-C. Fluorescence images of microbeads encoded with QDs emitting fluorescence at (A) 581 and (B, C) 515nm.
Panels D and F. Scanning probe nanotomography images of a QD-encoded microbead showing a detailed core/shell structure of the bead.
Panel E. Approximate estimation of the QD distribution in the outer subsurface area of the microbead measured by fluorescence intensity scanning.
Panel G. A sch. of the designed lab-on-a-bead system for detection of prostate-specific antigen (PSA).
Nanomedicine: Nanotechnology, Biology and Medicine  , DOI: ( /j.nano )
Copyright © 2015 Elsevier Inc. Terms and Conditions

3. Figure 2
The principles of experimental procedures and flow cytometry assay for simultaneous detection of free and total PSA in human serum samples.
Nanomedicine: Nanotechnology, Biology and Medicine  , DOI: ( /j.nano )
Copyright © 2015 Elsevier Inc. Terms and Conditions

4. Figure 3
Flow cytometry dot plots of uncoded versus QD-encoded 4.08-μm microbeads used for the detection of the free PSA form and total PSA.
Panel A. Light-scattering measurements of 4.08-μm melamine formaldehyde (MF) microbeads.
Panel B. Fluorescence dot plot of uncoded microparticles (a PE-A-negative, FITC-A-negative population).
Panel C. Fluorescence dot plot of microbeads encoded with QDs emitting at 515nm (green, a PE-A-negative, FITC-A-positive population) or 581nm (orange, a PE-A-positive, FITC-A-negative population).
Nanomedicine: Nanotechnology, Biology and Medicine  , DOI: ( /j.nano )
Copyright © 2015 Elsevier Inc. Terms and Conditions

5. Figure 4
Calibration curves for two PSA forms based on the results of calibrator sample analysis using the designed QD-based suspension microarray.
Panel A. Calibration curve for the determination of free PSA.
Panel B. Calibration curve for the determination of total PSA.
Each intra-assay analysis has been performed in triplicate.
Nanomedicine: Nanotechnology, Biology and Medicine  , DOI: ( /j.nano )
Copyright © 2015 Elsevier Inc. Terms and Conditions

6. Figure 5
Flow cytometry dot plots of the suspension array based on two microbead populations carrying different fluorescent nanocrystal codes that were used for simultaneous detection of free PSA and total PSA in clinical serum samples.
Panels A-D. Fluorescent codes of two different microbead populations were detected and differentiated in the PE-A channel; antigen binding was visualized and quantified in the PE-Cy5-A channel. A green (PE-A-negative, FITC-A-positive) microbead population was used for the free PSA detection, and an orange (PE-A-positive, FITC-A-negative) microbead population was used for the total PSA detection.
Panel A. Detection of two PSA forms in the serum of a healthy female donor (the PSA-negative control).
Panel B. Detection of two PSA forms in the serum of a prostate cancer-positive male patient (the PSA-positive control).
Panels C and D. Detection of two PSA forms in two clinical serum samples with different free and total PSA contents.
Panels E and F. Histograms showing the quantitative difference in the mean fluorescence intensity (MFI) reflecting the free and total PSA contents between the PSA-negative and PSA-positive control serum samples and two clinical samples. Red fluorescence shifts of different intensities in the PE-Cy5-A channel indicate binding of different amounts of PSA.
Nanomedicine: Nanotechnology, Biology and Medicine  , DOI: ( /j.nano )
Copyright © 2015 Elsevier Inc. Terms and Conditions

7. Figure 6
Comparison of the results obtained using the QD-based multiplexed suspension microarray and the single-analyte ELISA assay.
Panels A and B. Linear regression lines for the free (r=0.941) and total (r=0.948) PSA concentrations in clinical serum samples, were n is the number of samples. Data points are the mean values of free and total PSA concentrations determined in an intra-assay in triplicates using the QD-based suspension microarray and ELISA.
Panel C. Linear regression for the calculated percentage of free PSA relative to the total amount of PSA determined in the clinical serum samples (r=0.927). Data points are the values calculated by the equation: proportionofPSAfree%=PSAfreeconcentrationPSAtotalconcentration×100%, where the free and total PSA concentrations have been determined by the QD-based microarray or ELISA.
Nanomedicine: Nanotechnology, Biology and Medicine  , DOI: ( /j.nano )
Copyright © 2015 Elsevier Inc. Terms and Conditions

8. Nanomedicine: Nanotechnology, Biology and Medicine  , DOI: ( /j.nano )
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