Biological applications of gold nanoparticles.

This article reviews some of the recent biological applications of gold nanoparticles (GNPs) which have been discovered lately by individual studies all around the world. GNPs have emerged as a promising candidates for various biological applications due to their unique physical properties (size and shape dependent), excellent biocompatibility, facile synthesis, ease of bioconjugation, etc. This review starts with a brief introduction about nanotechnology followed by an insight into the history, emergence, and enhanced properties of various gold nanostructures, which form the basis for their numerous biomedical applications. In addition, a brief overview on some of the commonly used fabrication techniques for synthesizing GNPs is also discussed. Finally, a miscellany of the latest biological applications of GNPs, such as cancer diagnostics and therapy, biological probes, drug delivery, gene delivery, vaccine preparation, brain implants, artificial skin, sterilization system, and improving electrical signaling in the heart, published in different articles in reputed journals are highlighted.