A

A

A AR RT

T

T

T

Adaptive binding

Allosteric activation

A=Aptamer T=target R=Ribozyme

Apta-switch/beacon“OFF”

Apta-switch/beacon“ON”

“INPUT”Signal

“OUTPUT”Signal

AT

ModularDomains

“Functional”Aptamer

Your PlatformChoice implement

Negative/CounterSelection

5’

T7

PrimerExtension

5’

RNA library

Hammerhead ribozyme motif

N55

N55

5’

Mg++ dependentCleavage site

Transcription

Synthesized N55 random oligo library

Aptamer

pre

clv

PositiveSelection

RT-PCR

PAGEPartitioning

Promoter

Selection

PAGEPartitioning

(+) Target(-) Target(Buffer alone or Counter-target)

LibraryLibrary

Purify Pre-cleaved

Purify Cleaved

Random Region

Fluorophore

Optional:1. RT-PCR2. Transcription3. Refolding

Refolding

Apta-sw

itch Selection S

trategy

Monitoring Enrichment(Rounds of Selection)

(-) + (-) + (-) + (-) +

Target Example

Co2+, Ni2+, Cd2+

Zn2+, Mn2+

Caffeine

Rev Peptide

Phosphorylated ERK2,Unphosphorylted ERK2

Metal Ions

Small Organics

Peptides

Proteins

Apta-switch™ (aptamer that produces a self-cleavage output signal)

FlashGel™analysis

(5 minute run)

Apta-switch™Apta-switch™ Demonstration Kit Demonstration Kit(Theophylline/Caffeine)(Theophylline/Caffeine)

100 M

The

ophy

lline

Specificity Against Theophylline vs. Caffeine

100

90

80

70

60

Ladd

erDEPC o

nly

RXN Buf

fer o

nly

1 m

M C

affe

ine

100 M

Caf

fein

e10

M

Caf

fein

e

10

M T

heop

hyllin

e

1 M

Caf

fein

e1 M

The

ophy

lline

1 minute reaction at 23oC,then stopped with stop buffer containing excess EDTA.

1 m

M T

heop

hyllin

e

500-fold sensitivity range

Caffeine

Theophylline

“Forget Antibodies. Use Aptamers!”