sample cassette

Laser or LED

CCD camera or photo diode array

display

digital window sample holder

prismpolarizer lens

disposable sensor chip

cover plate

Compact SPR Biosensor

• For the sample with low concentration, signal shift might be smaller than environmental drift change.

• Self-referencing eliminates influence by environment (excellent robustness against temperature and buffer change).

substrate

PDMS flow cell

analyte

x

yz

Top view

Self-referencing SPR

Experimental procedure

glass slide

Ausubstrate

PDMS micro flow cell

Top view

Side view

width: 50 – 300 μm for channels and spaces between channels

Step 1

Step 2 Step 3

substrate

PDMS flow cell

x

y

z

channel width: 500 μm – 1 cm

glass slide

Au

solution

Multi-step functionalization procedure using mouse IgG as reference

glass slide

Au

sensing area

referencing area

MUA

antigen

mouse IgG

glass slide

AuS

OH

S

O

S S

OH

S

O

S S antibody

glass slide

AuS

OH

S

O

S S

OH

S

O

S S

glass slide

AuS

OH

S

O

S S

OH

S

O

S S

Taya, figs for pat appl, Aug 2005, fr Fengyu REV Aug 30.ppt

pbs

mouse IgG 100 g/ml

(a)

(b)

(c)

(d)

image pixel number

y ax

is o

f se

nsor

chi

pMouse IgG absorption onto the gold surface

(a)

(b)

(c)

(d)

image pixel number

y ax

is o

f se

nsor

chi

pAnti-CEA antibodies immobilized onto sensor chip

TKH2 20 g/ml STn 100 ng/ml

sensing (1)

referencing (2)

(1) - (2)

sensing (1)

referencing (2)

(1) - (2)

(a) (b)

Sensorgrams of TKH2 antibodies immobilizing onto sensor chip and STn antigens binding to TKH2 antibodies

sensing (1)

referencing (2)

(1) - (2)

CEA 10 ng/mlanti-CEA antibody 20 g/ml

sensing (1)

referencing (2)

(1) - (2)

(a) (b)

Sensorgrams of anti-CEA antibodies immobilizing onto sensor chip and CEA antigens binding to antibodies