Trends in Nanotechnology-based diagnostics: An overview
(Dr. Pradip Patel)IAFP, 18-20 May
2Content
Why the need?
Current technologies and market data
Nanotech-based diagnostics: Examples of hand-held and portable POC platforms
Bottlenecks and future prospects
3Drivers of Diagnostic Technology Development
Improve quality of patient care: Rapid therapeutic decisions based on paradigm shift from central lab to testing at Point-Of-Care (POC).
Food-borne illness
is a global issue. According to CDC&P (USA):~76 million cases annually; ~5000 deaths a year direct costs
$46 billion (lost productivity/health care)
Food quality/safety legislation
(e.g. EC Regulation 2073/2005 on microbiological criteria for foodstuffs linked with HACCP)
Food trade
(global competition)
Companies Internal food safety strategy
(HACCP, product right-first-time, due diligence, marketing)
Conventional methods
too time-consuming and labour-intensive
4Industrial Microbiology Market (courtesy of Tom Weschler, Strategic Consulting)
5TTR most important for critical care usersAcute Care/ Hospital
$1.1Bn
User needs are evolving, so no single platform likely to address needs of all 4 POC user segments
$4.1Bn
$9.4Bn
$0.3Bn
Physician Office Lab (POL)
Self-test / Consumer
Retail Clinic
POL prefer results in
6Current Microbiology Tests
Culture-based: media (Petri dishes, bottles, bags, tubes.)
Immunoassays: Manual/automated (ELISAs, lateral flow assays.)
Molecular amplification assays: Manual/automated platforms (RT-PCR, qRT-PCR, NASBA.)
Identification: Manual/automated ID systems (API, ATB, Vitek 2)
7Dynamic Industrial Needs!
Although current generation technologies adequately meet the needs of highly varied customer base (central & contract food and clinical labs, independent labs..), user requirements are continually changing:
Even lower analytical costs (often testing is viewed as a cost!)
Higher automation & integration with existing workflow
Reduced TTR (preferably results in few hours NOT days!)
No compromise on performance
High throughput with multiplex capability
Fit-for-purpose portable systems
Etc..
(Over the past decade, significant developments in nanotechnology, microfabrication (microfluidics, LOC devices), bioinformatics and connectivity have paved the way for technological developments that are expected to meet the challenges posed by the dynamic industrial needs)
8Frequently used Biosensor Principles in POC Nanotech-based Diagnostics
From: Luppa
et al., 2011. DOI: 10.1016/j.trac.2011.01.019
9Examples of POC Platforms
Hand-Held POC device (e.g. Philips Magnotech
biosensor)
Immunological principle
Nanomagnetic bead-based
Transduction mode: FTIR
Portable device (e.g. Biolithic StatAnalyser)
PCR-coupled CE chip
Detection: LIF
10
Magnotech Hand-Held POC Platform
Cartridge
for blood Analysis
is:8 mm X 3 cm
(Philips and bioMerieux are in partnership to develop POC devices for the IVD sector)
Quantitative detection ( nMpMand lower ) from a small droplet ( 15-40 L
) of whole blood
within minutes with
high reliability
multiplexed in a cost-effective cartridge with
a compact analyser
Courtesy of Jeroen Nieuwenhuis (Philips Healthcare Incubator)
11
Courtesy of Jeroen Nieuwenhuis (Philips Healthcare Incubator)
Principle of Magnotech Assay
Target capture
Fast target capture
Magnetic attraction
Analyte concentration
Magnetic removal
Effective bound/free separation
12
Frustrated Total Internal Reflection (FTIR) Readout Principle
Courtesy of Jeroen Nieuwenhuis (Healthcare Incubator)
13
Typical FTIR Signal Sensorgram
Signal decreases when beads bind to the surface due to scattering and absorption of the evanescent field
Courtesy of Jeroen Nieuwenhuis (Healthcare Incubator)
1414
Sandwich Assay: Cardiac Troponin I (TnI)
100% plasma 5 minutes dry reagents
0 .10
1 .00
10 .00
100 .00
0 .01 0 .1 1 10
Signal(%)
Concentrat ion(ng/m l)
TnIdose response
Courtesy of Jeroen Nieuwenhuis (Healthcare Incubator)
PresenterPresentation NotesSignificance: Good linear range of almost 3 orders of magnitudeSignificance: the LOD is well below 1 pM (1 pM = 0.0259 ng/ml)
15
Portable StatAnalyser: Core PCR-CE chip(Courtesy of Maz Khorasani; Biolithic corp)
16
Bakulovirus Detection by PCR-CE Chip (Kaigala
et al (2010), Analyst, 135, 1606)
The PCR product peak (299 bps) represents the presence of BK virus in a sample LOD quoted is about 20pg/uL
(similar to agarose
gel/ethidium
bromide method)
17
StatAnalyser: Essentially a LOC Toolkit(Courtesy of Maz Khorasani; Biolithic corp)
Sold as modular portable toolkit for POC application, NOT
as final assays
Performance claim:equivalent to other
expensive
commercial systems
The entire system in its current form is shoebox-sized Total component cost of ca. $600!
18
So, what are the Bottlenecks?
Sample matrix complexity
Background components
Compositional variability
Potential interference from
non-target flora
PCR
iInhibitors
Lengthy analysis
times due to inevitable
cultural growth steps
Thus, results
are generally only
of retrospective
value
19
Schematic of a Typical Meat Homogenate
Patel(2000). J.Rap.Meths. & Automa. Microbiol., 8, 227-248
20
Dielectrophoresis (DEP) : Selective Isolation of Live from Dead Human Leukemia Cells
No electric
field: Dead (red) and live (blue) cells
moving
right to left
.
Electric field
(30 s):
live cells
are trapped(+ve
DEP); dead
cells
pass
by
Power supply
off: live cells
released
From: Shafiee et al., 2010. DOI: 10.1039/b920590j
21
Prospects
Developments
in capture/concentration as alternatives/adjuncts
to cultural growth
Improved
high
productivity/selectivity
media
Recent
technological
developments
in microfabrication, microfluidics, LOC, multiplexing
and bioinformatics
and IT communication devices
Overall, integration
of the above
areas are expected
to deliver
the next
generation
diagnostic technologies
Slide Number 1Content Drivers of Diagnostic Technology DevelopmentIndustrial Microbiology Market (courtesy of Tom Weschler, Strategic Consulting)User needs are evolving, so no single platform likely to address needs of all 4 POC user segmentsCurrent Microbiology TestsDynamic Industrial Needs!Frequently used Biosensor Principles in POC Nanotech-based Diagnostics Examples of POC Platforms Magnotech Hand-Held POC PlatformPrinciple of Magnotech AssayFrustrated Total Internal Reflection (FTIR) Readout PrincipleTypical FTIR Signal SensorgramSandwich Assay: Cardiac Troponin I (TnI)Slide Number 15Slide Number 16Slide Number 17So, what are the Bottlenecks? Schematic of a Typical Meat Homogenate Dielectrophoresis (DEP) : Selective Isolation of Live from Dead Human Leukemia Cells Prospects