Curcumin-Conjugated Gold Clusters for Bioimaging and Anticancer Applications

Abstract

Curcumin-conjugated gold clusters (CUR-AuNCs) were synthesized using a "green" procedure and utilized as an anticancer and a bioimaging agent. Curcumin is a well-known anticancer agent, which forms a cluster when reacting with a gold precursor under mild alkali condition. A fluorescence spectroscopy analysis showed that the CUR-AuNCs emitted red fluorescence (650 nm) upon visible light (550) irradiation. Fourier transform infrared spectroscopy analysis confirmed the stretching and bending nature between the gold atoms and curcumin. Meanwhile, transmission electron microscopy analysis showed a cluster of approximately 1-3 nm with a uniform size. Time-resolved fluorescence analysis demonstrated that the red fluorescence was highly stable. Moreover, laser confocal imaging and atomic force microscopy analysis illustrated that a cluster was well distributed in the cell. This cluster exhibited less toxicity in the mortal cell line (COS-7) and high toxicity in the cervical cancer cell line (HeLa). The results demonstrated the conjugation of curcumin into the fluorescent gold cluster as a potential material for anticancer therapy and bioimaging applications.

Retention of Anticancer Activity of Curcumin after Conjugation with Fluorescent Gold Quantum Clusters: An in Vitro and in Vivo Xenograft Study

“… 40 Similarly, the two bands present in the spectra of both curcumin and C-Au QCs at 1458 and 1024 cm –1 (indicated with pink color fonts) are due to the mixed vibration of CH 3 and aromatic −C=C–C, respectively, which confirmed the presence of curcumin as a capping agent. 65 …”

Nanoformulations to Enhance the Bioavailability and Physiological Functions of Polyphenols

“…Traditional gold nanoparticles are synthesized using chemicals that are harmful to human health and the environment [ 283 ]. In recent years, numerous gold nanoparticles have been prepared using plant active compounds that are friendly to the human body and the environment, such as polyphenols [ 284 ]. Curcumin (Cur) is the most widely used plant active compound in the preparation of gold nanoparticles ( Figure 10 ).…”

“…This feature makes them useful for biological imaging. Compared with the control group, curcumin-conjugated gold clusters (Cur-AuNCs) significantly inhibited the migration of HeLa cells and exhibited significant cytotoxicity [ 284 ]. Other polyphenol compounds can also participate in the synthesis of gold nanoparticles.…”

“…( C ) Bio-AFM height image of CUR-AuNCs. Adapted from reference [ 284 ]. Copyright 2018 American Chemical Society.…”

Preparação de nanobiosistemas para detecção do microRNA tumoral miR-21.

“…Muitas dessas nanopartículas são usadas em aplicações biomédicas porque oferecem muitas vantagens em comparação com partículas maiores, como aumento da razão superfície/volume e propriedades magnéticas [98]. Nosúltimos anos, diferentes estudos têm sido realizados para avaliar o potencial das nanopartículas para serem usadas em biossensores, bioimagem, liberação de fármacos, terapia por hipertermia e terapia fotodinâmica [99][100][101][102][103][104]. Paralelamente tem se buscado otimizar as propriedades das nanopartículas controlando os processos de síntese e funcionalização da superfície.…”