BIOBARCODE USING BIOBARCODE USING NANOTECHNOLOGYNANOTECHNOLOGY

DR. GURPREET SINGH, Ph.D, FSAB

PG DEPARTMENT OF BIOTECHNOLOGY, LYALLPUR KHALSA COLLEGE, JALANDHAR

PUNJABEMAIL: drgurpreet@lkc.ac.in

BARCODEBARCODE: A barcode is an optical machine-readable representation of data, which shows data about the object to which it attaches. Originally, barcodes represented data by varying the widths and spacings of parallel lines, and may be referred to as linear or 1 dimensional (1D), rectangular or geomatrical shapes (2D). 3D barcode uses the height of the line to represent a product.

1D 2D 3D

DNA barcode• DNA barcoding is a taxonomic method that

uses a short genetic marker in an organism's DNA to identify it as belonging to a particular species.

The basic concept of bar-code DNA. It carries with it a large number of oligonucleotides per protein binding event, there is substantial amplification and one can detect PSA at 30 attomolar concentration.

Alternatively, one can do polymerase chain reaction on the oligonucleotide barcodes and boost the sensitivity to 3 attomolar.

http://ho.seas.ucla.edu/wp-content/uploads/2011/04/Wei_Ho_PediatricResearch2010_review.pdf

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Bio-Bar-Code-Based DNA Detection with PCR-like Sensitivity J. AM. CHEM. SOC. 2004, 126, 5932-5933

Ho et al., 2005. Multiplexed Hybridization Detection with Multi color Colocalization of Quantum Dot Nanoprobes. Nano Lett., Vol. 5, No. 9, 2005

Sequences of the Three Anthrax-Related Targets (rpoB, capC, and pagA) and Their Associated Oligonucleotide Probes.

Simulated multiplexed analysis of anthrax-related genetic targets for pathogenicity: (a) color pallet for the three pairs of targetspecific QD nanoprobes and their resulting colocalized fluorescent images upon sandwich hybridization; (b) four samples containing different combinations of the three targets, rpoB, capC, and pagA. Checks represent the existence of certain target sequences. Sample IV does notcontain any target and is used as a negative control. (c) Fluorescent images I, II, III, and IV correlate with samples I, II, III, and IV, respectively.

Programmed Assembly of DNA-Functionalized Nanoparticles

Magnetic ParticleProbe

Target Protein

Nanoparticle Probe with Barcode DNA

Separation using magnetic field &Bardcode DNA dehybridization

Barcode DNA

Signal Amplification by PCR

Chip based detection of Barcode DNA

a : complementary capture DNAb : non complementary capture DNA

atto molar detection!!atto molar detection!!

Nanoparticle-Base Bio-BarcodesNanoparticle-Base Bio-BarcodesUltrasensitive Protein Detection

The system is based on magnetic microparticle probes with antibodies that

specifically bind a target of interest [prostate specific antigen (PSA), amyloid

beta oligomer] and nanoparticle probes that are encoded with DNA that is

unique to the protein target of interest and antibodies that can sandwich the

target captured by the microparticle probes .

Magnetic separation of the complexed probes and target followed by

dehybridization of the oligonucleotides on the nanoparticle probe surface

allows one to determine the presence of the target protein by identifying the

oligonucleotide sequence released from the nanoparticle probe

Nanoparticle-Based Bio-Bar Codes for the Ultrasensitive Detection of Proteins

Nanoparticle-Based Bio-Bar Codes for the Ultrasensitive Detection of Proteins

Nam et al., Science, 301, 1884-1886, 2003