gold nanoparticles applications and challenges

MATHEW THOMAS MALIAEL

DAYANANDA SAGAR COLLEGE OF

DENTAL SCIENCES , BANGALORE

NANOPARTICLE• According to International Union Pure and Applied Chemistry,a particle of any shape

with dimensions in the 10^-7 m to 10^-9 m range is termed as a nanoparticle.

• Nanometer-sized particles have optical, magnetic, chemical and structural propertiesthat set them apart from bulk solids, with potential applications in medicine.

TYPES OF NANOPARTICLES

• Carbon nanotubes

• Carbon nanowires

• Iron oxide shells

• Gold nanoparticles

• Silver nanoparticles

• Cadmium selenide quantum dots

Does all Gold Glitter?

GOLD(AU)

• Gold (Latin -aureum) is a bright, slightly reddish yellow, dense,soft, malleable ,ductile and an inert metal.

GOLD NANOPARTICLES (AUNP)

• Gold nanoparticles is alsocalled colloidal gold.

• Nano-sized gold colloids canappear blue or red in color.

HISTORY OF GOLD NANOPARTICLES

• In 1857, Faraday first synthesised colloidal gold by reducing gold chloride using phosporous.

• During the 20th century , techniques like transmission electron microscopy and atomic force microscopy enabled the direct imaging of nanoparticles.

SYNTHESIS OF GOLD NANOPARTICLES

FORMS OF GOLD NANOPARTICLES

WHY GOLD NANOPARTICLES???

Bio-inertReadily

dispersedReadily

functionalised

High X-Ray attenuation

Readily synthesised

APPLICATIONS

• Targeted delivery of drugs and other biomolecules.

• Detection of biomarkers of various diseases and conditions

APPLICATIONS

GOLD NANOPARTICLES

NANO ONCOLOGY

NANO IMMUNOLOGY

NANO CARDIOLOGY

NANO IMAGING

THERAPUETICS

NANO NEUROLOGY

NANO ONCOLOGY• Contrast media in optoacoustic imaging of

cancer.

• Targeted delivery of chemotherapeutic agents.

• Photo-thermal therapy of tumours.

• Identification of biomarkers.

• Radio-sensitizers

NANO NEUROLOGY

Spivak et al. The EPMA Journal 2013, 4:18

NANO CARDIOLOGY

• Targeted delivery of cardio-protective drugs.

• Activate metabolic processes to reduce BP , thereby improves blood circulation.

• Potentially intervene in lipo-protein matrix in atherosclerosis.

• Identification of biomarkers.

Spivak et al. The EPMA Journal 2013, 4:18

NANO IMMUNOLOGY

• Applications include rapid tests such as lateral flow, vertical flow, western blots and dot-blot assays.

• Gold nanoparticles are effective vaccine adjuvants and enhance the immune response via different cytokine pathways depending on their sizes and shapes.

Demenev V.A., Shchinova M.A., Ivanov L.I., Vorob’eva R.N., Zdanovskaya N.I., Nebaykina N.V..Vopr. Virusol. 1996;41:107–110.

THERAPUETICS

In 1997, the successful application of colloidal gold in a patient with rheumatoid arthritis was first reported

In 2008, a vast array of data on the ten-year-long clinical trials of the preparation Aurasol ® for administration upon severe forms of rheumatoid arthritis was published.

Abraham G.E.. Orig. Intern. 2008;15:132–158

NANO IMAGING

• Gold induces a strong X-ray attenuation, hence they are used as optical imaging probes.

• Various types of targeted nano-probes have been developed for optical and MRI molecular imaging.

• More recently, hybrid nanoparticles such as anti-biofouling polymer-coated gold nanoparticles ,gadolinium coated gold nanoparticles. polymer-coated Bi2S3

nanoparticles have been developed as vascular CT contrast agents.

Rabin O, Perez JM, Grimm J, Wojtkiewicz G, Weissleder R. An X-ray computed tomography imaging agent based on long-circulating bismuth sulphide nanoparticles. Nature

Materials. 2006;5:118–122.

Lamerichs R. MRI-based molecular imaging using nano-particles. Cellular Oncology. 2008;30:100–10

ADVANTAGES

Gold nanoparticle is simple for diagnosis.

Less invasive Provides

increased contrast for diagnosis

DISADVANTAGES

Relatively weak

optical signal

Long term

cytotoxicityEfficiency

Factors affecting

pharmacological properties

need to be clarified

Long term cytotoxicity effects

must be studied

Eliminate the inflammatory and

immune response triggered by

some polymer coatings

Economics

Challenges

CONCLUSION

• Nanotechnology can play an intimate role in individualized medicine with potential enhancements increasing the affinity of the nanoparticle for cancerous cells and amplifying the uptake of diagnostic and therapeutic moieties into diseased cells with greater efficiency.

“ Gold nanoparticles may provide a new light into the applications spanning right

from gene-regulation to diagnostic imaging as a promising novel agent!!!!......”

REFERENCES• Huang XH, El-Sayed IH, Qian W, El-Sayed MA. Cancer cell imaging and photo

thermal therapy in the near-infrared region by using gold Nano rods. Journal of the American Chemical Society. 2006;128:2115–2120.

• Alric C, et al. Gadolinium chelate coated gold nanoparticles as contrast agents for both X-ray computed tomography and magnetic resonance imaging. Journal of the American Chemical Society. 2008;130:5908–5915.

• Agarwal A, et al. Targeted gold nanorod contrast agent for prostate cancer detection by photoacoustic imaging. Journal of Applied Physics. 2007;102.

• 0. Jiang W., Kim B.Y.S., Rutka J.T., Chan W.C.W. // Nat. Nanotechnol. 2008. V. 3. P. 145–150.

• Kennedy L.C., Bickford L.R., Lewinski N.A., Coughlin A.J., Hu Y., Day E.S., West J.L., Drezek R.A.. Small. 2011;7:169–183.

Thank You!!!