Portable SPR instrument: From research to clinical applications

Jean-François MassonUniversité de Montréal

Photonics North 2014 – Parlons Affaires

• Scientific equipment for the research, industrial applications and clinical diagnostics

• Innovation:– Small and portable SPR instrument– Surface chemistry to analyze crude biofluids– Nanomaterial to amplify response from instrument

Field of the innovation

Commercial SPR instrument – lab-based

• Pros: High sensitivity, reliability and automation

• Cons: High cost of acquisition, operation and maintenance, not possible to use biofluids

Commercial SPR instrument – Portable

• Pros: portability, low acquisition cost

• Cons: Poorer performance, maintenance, user-friendliness, low number of sensing channels (typically 1-2)

Integrated portable SPR instrument

Features

• Sensitive• 10-6 RIU resolution• Computer powered with USB – no external power cord• No RI matching fluids• Simple injection system• 4-channels including a reference• Simplicity• Versatility• Performance• Portability• Customizable• Low maintenance• Low cost• Low weight (less than 1.3 kg)• Quiet operation

• Calibration run with 3 channels (A-C active), background subtracted with channel D– Triplicate repeat of calibration point 2 at the end of the run

Industrial application – Salinity measurement

Reproducibility < 1% and the channel to channel variation < 10%

R2 = 0.9998% CV = 0.6 to 8%Repeatability: 0.4 %(6.02 ± 0,02) nm

• EP80317: anti-atherosclerotic property mediated by CD36 • interfering with the binding of oxLDL to the scavenger receptor

expressed on macrophagesLigands SPR

Kd (10-6M)SPR

∆λSPR (nm)

CP-3(ii) 67 0.33CP-2B(i) 31 0.54

CP-1A(iv) 10.2 2.17CP-2B(v) 4.66 2.19CP-2A(v) 2.86 1.92EP80317 2.75 2.64

DBG-178(27) 0.77 2.22 CP-3(iv) 0.72 2.10GHRP-6 25.6 2.13

Screening growth hormone-releasing peptides (GHRPs)

Type B scavenger receptor CD36 (CD36: cluster of differenciation 36)

Methotrexate – chemotherapy agent

• Drugs with a narrow therapeutic window must be carefully controlled to ensure patient’s safety, proper metabolism and drug efficacy

• Common analytical techniques are laboratory-based, time-consuming or expensive to run

• The development of a small and portable instrument with a simple and dedicated set of reagents would address some of the current challenges in TDM

Therapeutic drug monitoring

• The samples were deidentified and analyzed in a blind assay with FPIA (independant analyst) and with LC-MS/MS and SPR (different analyst SZ)– FPIA analysis results were only known after final report from SPR and

LC-MS/MS

Quantification of MTX in clinical samples with SPR instrument

Collaboration with a local hospital to analyze actual clinical samples

• The system was deployed at Hosp. Maisonneuve-Rosemont to evaluate the performance in a real environment

• The SPR system is running on power supplied by the portable computer– Ease of portability

Calibration from different operators and locations

Calibrations were run in UdeM laboratories and at local hospital

10 uM Day 1CV = 4-8%

0 uM Day 2CV = 6-16%

50 uM Day 2CV = 9-23%

0.01 0.1 1 10 100-5

0

5

10

15

20

25

Concentration anti-asparaginase /μM

ΔλSP

R,m

oyen

/nm

Acute lymphoblastic leukemia

Measuring the immune response during treatment

• Some patients respond to asparaginase treatment by developing antibodies, leading to ineffective treatment and allergic reactions

• Monitor antibody concentration by immolizing the drug (asparaginase) on the SPR sensor

SPR sensor

His-tag Asparaginase

12

***Ratio of PSA + Ab-2 (1:1) usedLD: 0,1 nM

Screening method:• Digital rectal exam:

– Low cost– Unpleasant– Only screen a section of the prostate

• Prostate specific antigen (PSA) test:– Protein secreted by the prostate cells– Level measure in a blood sample– Complementary to digital rectal exam for

an accurate diagnostic

Protein biomarkers

Prostate-specific antigen (PSA)

Multi-channel SPR and fluorescence instrument:

13

Fluorescence

Interfacing with other spectroscopic techniques

SPR-fluorescence

• SPR and fluorescence are orthogonal techniques that can be combined in a small instrument

SPR

Fluorescence

SPR

• Fluorescent antibody used: Cy3 Anti-Human-IgG

• Using microstructured gold film could improve the fluorescence emission

Positive control (1000nM IgG immobilized)

SPR Fluorescence

Proof-of-principle with SPR-fluorescence bioassay

• Research (ready to market)– Ligand screening– Binding assays– Optical research / Surface-enhanced spectroscopies

• Industrial applications (partially validated)– Refractive index measurement– Fermentation processes

• Clinical diagnostics (in process ofvalidation)– Biomarkers– TDM

Different markets accessible

Acknowledgements

Current research group:Dr. Natalia BukarDr. Hélène Yockell-LelièvreDr. Kristy McKeatingDr. Marc VidalSandy Shuo Zhao *Julien B.-TurcotMaxime CoutureHugo-Pierre P-RichardRita FaidAlexandra AubéHu ZhuSimon ForestDaniel Pelechacz *Félix LussierJérémie L.-CarbonneauGeneviève GrangerGabrielle L. LajoieCorentin Geny

* Alumni