Gold nanoparticle (AuNP)-based drug delivery and molecular imaging for biomedical applications

Abstract

Gold nanoparticles (AuNPs) can be readily synthesized and modified with chemical and biological molecules, making them attractive inorganic biomaterials for drug delivery and molecular diagnostics. The surface of AuNPs supports the efficient attachment of various biomacromolecules via chemisorption, chemical conjugation and electrostatic interaction. Based on advantages of facile surface modification and unique optical properties, AuNPs have been extensively used as drug carriers for the intracellular delivery of therapeutics as well as molecular nanoprobes for detection and monitoring of the target molecules of interest. In this review, we highlight advanced approaches in the biomedical applications of AuNPs such as gene and drug therapy, molecular diagnostics and imaging.

Gold nanoparticles: A promising therapeutic approach

“…These complexes provide better protection of the encapsulated drug from enzymatic metabolic degradation, allowing prolonged half-life (t 1/2 ) and improved of layers. Further, the delivery to a target cell can be achieved AuNP surface (38).…”

“…Viral and non-viral systems have been most frequently used for gene delivery. However, the viral and non-viral systems have limitation for causing immune nanoparticles are considered suitable candidates for gene delivery, since they not only provide a high surface-to-volume ratio but also have a small size that maximises payload to carrier ratio (38,39).…”

“…This is so because the PEGylation under the normal cell culture conditions stabilizes the AuNP/DNA complex by providing it Singh, Kaur, Kaur, Buttar and Bhullar with a protective layer for a longer time period. This procedure helps to increase transgene expression and reduces cytotoxicity (38). These functionalized nanoparticles are also used for the delivery of amino acids and small interfering RNA (siRNA) (9,(42)(43)(44)(45)(46)(47)(48)(49).…”

“…When this nanocomplex is transported into the cell, free siRNA is released by the reductive cytoplasmic addition, the end-functionalized siRNA can also be coupled to the polymer coated AuNPs through chemical linkages. Acidliable or reducible bonds can be used for selective delivery of conjugated siRNAs under acid-pH or reductive environment of the cells (38). The photo-cleavable linkers are also used for the delivery of adsorbed genetic material.…”

Nanobiomaterials for pharmaceutical and medical applications

“…Carbon allotropes such as graphene oxide, carbon nanotubes, and nanodiamonds (NDs) are utilized for the delivery of water insoluble drugs, antigens, antibodies, and nucleic acids to the cancer cells. The last article in nanoparticle systems describes the gold nanoparticle (AuNP) based drug delivery and molecular imaging by Lee and colleagues (Jeong et al 2014). Surface modifications of AuNPs and their applications in delivery of small chemical drugs as well as gene materials such as pDNAs and siRNAs are discussed.…”