nmed presentation
TRANSCRIPT
Development of Hand-held Instrument for STI Diagnostics
Professor.((W.(Balachandran((Bala)(Director((of(the(Centre(For(Electronic(Systems(Research(
School(of(Engineering(&(Design(Brunel(University(
March 2013 1"
Enabling(and(TranslaGng(Advances(in(DiagnosGc(and(CommunicaGon(Technologies(to(Reduce(the(Burden(of(Sexually(
TransmiJed(InfecGons(
Self Testing Instrument for Sexually Transmitted Infections
Taking laboratory diagnosis into the field
Integrated System for POCT
3"
((((((Wireless(((((((Interface(
DNA(ExtracGon((&(PurificaGon((
Sample(collecGon( MicroFluidic(Network((
DNA((DetecGon(
Electronic(Control(System(
DNA((AmplificaGon(
Sample(concentraGon((&(cell(lysis(
The Team
Professor"Wamadeva"Balachandran"(Bala)"Principal(InvesGgator
Dr"Jeremy"Ahern"MicrofabricaGon Dr"Nada"Manivannan"
MulGphysics(Modelling Professor"Chris"Hudson"Electronic(Engineering(
Professor"Rob"Evans"
Biosciences(
Dr"Predraig"Slijpevic"""
Biosciences
Pascal"Craw"PhD(Student(
Biomedical(Engineering(
Branavan"Nehru"PhD(Student(
Paper(microfluidics(
Dr"Yanmeng"Xu"Printed(Electronics(
Sara"Chaychian"PhD(Student(
Electrical(Engineering(
Tosan"Ereku"PhD(Student(
Engineering(Design(
Dr"Krishna"Burugapalli""""""Biomedical(Engineering
Shavini"Wijesuriya"PhD(Student(
Engineering(Design(
Sana"Hussain"VisiGng(Scholar(Biosciences(
Sivanesan"Tulasidas""PhD(Student"Wireless(
CommunicaGon"""
Dr"Ruth"Mackay"BioMEMS/NEMS
Modular Research Platform
Electromagnets
Lysis
AmplificaGon
DetecGon
Sample(&(Reagents
Waste
Disposable(Cartridge
GPSRFID
Bluetooth( 3G(Mobile
USBWiFi
Microcontroller(
Power(Management(
Display(and(User(Interface
MagneGc
Electrochemical
OpGcal(
SPR
MEMS
Nanowire
Nucleic(Acid(Detector(
Pumps
Valve(actuators
Thermal(control
StandardisaGon
ConcentraGon(/(PurificaGon
Sample(preWtreatmentElectronic(System
Control(System(
CommunicaGon(
Interface
Valves
Sensors
Electromagnets
Microfluidic(Network(
Pathways
Sample Collection
• Swab and urine • 4mL of urine • 100uL swab elute • Simple design ‘Fool-
proof’ • Direct integration to
extraction device • Integrated lysis
Urine collection devices
FE Analysis to Inform Design
Streamline depiction of flow from inlets to device discharge orifice
CessaNonal" flow" of" urine" from" six"inlets"into"the"airQfilled"cavity"
DNA Extraction using Superparamagnetic Beads
8"
Ports
Coil recessCentral stub to Assist
the Coil Location
1 mm PMMA
Side Via to Port
500um PDMS
9 mm
Port Position
9 mm Coil Recess Diameter
Position of Chamber in PDMS Layer
12mm Pitch Circle for Ports
Chamber Cut-outPort Vias
8 mm
(a)
(b)
(c)
Microfluidic Chamber
Stainless Steel Port-ways
Polystyrene Collars
250mm Bore PVC Tubing
A photograph of microfabricated chamber with PVC tubing
Microfluidic Dispenser
DNA Extraction using Cationic Biopolymer
• Novel membrane in development • Cationic bioploymer membrane • Reduces number of steps for DNA
extraction • No toxic reagents • Simple pH (5-9) change in aqueous
solutions • 2 reagents required • Simple f low over device: no
centrifugation/active mixing
Two(DNA(extracGon(devices(with(embedded(biopolymer(membrane(
DNA Extraction Performance
0"
10"
20"
30"
40"
50"
60"
70"
80"
90"
100"
0" 0.1" 100"
Percen
tage(Recovery(((%
)(
Sample(ConcentraGon((ng/uL)((Salmon(sperm(DNA)(
Spin"Column"(Qiagen)"
Bioplymer"membrane"
Lab-in-a-Tube
Biopolymer and Lysis buffer will be integrated into the device to extract DNA
Cell Lysis and DNA Extraction"
0"
1"
2"
3"
4"
5"
6"
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8"
9"
10"
Standard"25µL""tube"rea
OnQchip"25µL"reacNon"
Final"D
NA"concen
traN
on"(u
g/mL)"
On-chip helicase dependent amplification
Isothermal Amplification • Helicase dependent
amplification • Single temperature (65�C) • 109 amplification power • < 20minutes reaction time • Can be used with real-time
fluorescence chemistries RealWGme(plot(of(HDA(reacGon(
Fluo
rescen
ce"
Time"(minutes)"0""""""""""""""""""""5"""""""""""""""""""""10""""""""""""""""""15"""""""""""""""""""20"""""""""""""""""""25"""""""""""""""""""30"""""""""""""""""""35""""""""""""""""""40"
NegaNve"control"
PosiNve"Control"
On-chip Amplification and Detection
Fluorescence"detecNon"on"microfluidic"chip"
0"
490nm"LED"
Amplified"Photodiode"
Emission"bandQpass"Filter""(530nm)"
OpNcal"Fibre"3mm"PMMA"
ReacNon"Chamber"
PMMA"Fluidic"Chip"
Finite"element"analysis"of"microfluidic"chip"to"characterise"thermal"properNes"
25µL"microfluidic"chip"
Planar Spiral Inductor for Inductance-based biosensor
Magnetic Bead-based DNA Detection
Silver"NPs;"a)1,"b)5"and"c)10µl"Hydrazine"in"0.1M"AOT/IPM"microemulsions"
Gold"NPs;"e)"1,"f)5"and"g)10µl"Hydrazine"in"0.1M"AOT/IPM"microemulsions"
a" b" c"
e" f" g"
Nano-particle/bead fabrication
Inductance Sensor: Simulation
(Circular(planar(coil(I(=(100(mA,((N(=(5((Maximum(electric(potenGal(=(160((mV(MagneGc(Flux(Density(=((4"Q"16(mT((
(Square(planar(coil(I(=(100(mA,((N(=(5((Maximum(electric(potenGal(=(110((mV(MagneGc(Flux(Density(=((4"Q"12(mT((
18"
Effect of dout on δL Effect of Beads Permeability µrB on δL
tc =2µm
tc =2µm
19"
Effect of Conductor Thickness tC on δL Effect of Thickness of Underlying Permalloy tp on δL
The Effect of Frequency on Sensor Output
Brass/Al"mould"for"a"detecNon"microfluidic"device"
DetecNon"device"with"automated"fluid"flow"and"electrodes"
Al"mould"for"a"fully"integrated"microfluidic"system"
Integrated"microfluidic"PDMS""device"
10mm"
10mm"
10mm"
Integrated Microfluidic Cartridges
Communication Design Strategy
Paper based microfluidics (µPADs)
Fabrication of µPADs
Wax"penetraNon:"comparison"of"printed"barriers"before"and"aher"curing"at"120oC"for"15"minutes"
Printed"barriers"of"500"µm"produced"fully"funcNonal"barriers."A"minimum"channel"width"of"~"300"
µm"is"achievable."
Printed"barriers"(Wax)"
Cured"barriers"(Wax)"
Xerox"ColorQubeTM"8570N"solid"ink"
Printer"
MulNplexing:"A"single"sample"effecNvely"
delivered"into"5"test"zones"
DNA"mobility"on"a"µPAD"
Inkjet"printed"silver"electrodes"(25"µm)"
DNA Detection on µPADs
0(s( 30(s( 90(s( W(1( W(2( 0s"–"A"blank"test"device"as"a"control"before"introducNon"of""""FITC"tagged"25mer"DNA"sample"(0.01nM).""
30s"–"DNA"sample"moving"within"the"hydrophilic"channel.""
90s"–"Further"movement"of"the"sample"into"the"waste"zone.""
W1"–"DNA"sample"gelng"washed"away"by"water"into"the"waste"zone.""
W2"–"Further"washing"of"the"DNA"by"water"into"the"waste"zone."
Water"as"control""
Blank"paper"as"control""
Serially"diluted"0.1pM"DNA""
Serially"diluted"1pM"DNA""
Serially"diluted"0.01nM"DNA""
Stock"DNA"soluNon"0.1nM"
All"above"pictures"are"obtained"through"the"BIOQRAD"Gel"DOCTM"XR+"system"and"the"associated"image"analysis"sohware"Image"LabTM."""
Handheld Device Development
The current handheld system development
Future GUI