Date post: | 25-May-2015 |
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Early Detection of Cancer Cell Optical Sensor
Dr.Asok K.Dikshit
Glocal UniversitySaharanpur, UP
Cancer pathology
● It is a generic group of diseases● It can affect different parts body
Why Cancer occurs?
It is mutations in genes that control cell cycles
Types of cancer cell
Four types● Uncontrolled growth of Cell● Invasion of adjacent tissue● Merastasis-spreading to other locations in the body● Immortality -protection against programmed cell death
All cancer cells show irregular cell cycle control
Tumor has size grown 1 mm, it develops new blood vessels (angiogenesis)
Nanoparticles applications in three major area:
● Drug and gene delivery● Biosensing● Bioimaging
Protein–nanoparticle conjugation by Electrostatic targeting of ChT by anionic NP;
Nanoparticles effectively binds with protein
Nano particles in Biosensing
Complexation of ChT with anionic nanoparticles and its release mechanisms by addition of various surfactants
Nanoparticles makes them excellent materials for Forster resonance energy transfer (FRET)-Nanoparticles makes them excellent materials for Forster resonance energy transfer (FRET)-based biosensorsbased biosensors
In this approach, the dye molecule is on the surface of the nanoparticle surface in the In this approach, the dye molecule is on the surface of the nanoparticle surface in the absence of the target DNA strand /cell due to hairpin structure of the attached DNA, resulting absence of the target DNA strand /cell due to hairpin structure of the attached DNA, resulting in fluorescence.in fluorescence.
Silica NP
Silica NP
(A) Normal cells only have a
small amount of HER2 on their
surface.
(B) In 25% of invasive breast
cancers, cells have a
malfunctioning gene that
causes too much HER2 on
their surface.
Biomarkers of cancer include proteins over expressed in blood and serum or at the surface of cancer cells that facilitate diagnosis.
HER2 is a receptor of tyrosine kinase family
No biomarker has been established as an‘‘ideal’’ cancer screening tool because of the lack of sensitivity and specificity of the current tests.
Ref: A.K.Dikshit, Optical Materials, 34,1054,2012
TEM images of the enzyme labelled SiNP probes (a) and bare SiNPs (b)
FE SEM images of the insitu fabricated silica nanoparticles (SiNP)
TEM images of the labelled silica naoparticles ( SiNP)
TEM diffraction images of the SiNP
Fluorescence: A light emission is provoked by the excitation of certain
molecules called fluorophores. Biological imaging using fluorophores for
the diagnostic and imaging of cancer cells in microamounts for earlier
detection.
When conjugated with target molecules, fluorophores can be attached to
cancer biomarkers or cancer cells allowing the detection of cancer.
Reference: (1) A.K.Dikshit, Optical Materials, 34,1054,2012(2) A.K.Dikshit et al, Optical Materials, 35, 78, 2013
Silica nanoparticles
Silica NPs (SiNPs) are electroactive and have been used for biomarker detection
Proposed Sensor probe
Laser dye attached Silica nanoparticles
Laser dye attached
Cancer cells can produce on their surface an abnormal quantity of proteins, receptors or specific enzymes.
These over expressed components can be detected and bound in order to detect, isolate, quantify and destroy tumour cells by Si NP.
As an example, HER2 is a receptor of tyrosine kinase family.
An over expression of HER2 is present in 25% of invasive breast cancer cells.
The detection of cancer cells via the use of nanoparticles is an emerging sensor
The interaction of antigen and antibody provoked an emission of fluorescence
from silica NPs. This fluorescence has been analysed by laser scanning
microscopy and Fluorescence spectrophotometer.
Advantages:
(I)Low Cost, and low quantity sample needed
(II)NPs can be incorporated into user-friendly devices
(III) Immunoassays using NPs are very specific and sensitive
This Optical Sensor probe can detect cancer cell in
micro amounts by optical imaging in the early stage.
Looking forward collaboration with
1.Mastrict Clinic, Netherland2. National Cancer Institute(NCI),USA
.
Thank you