Doxorubicin conjugated gold nanorods: a sustained drug delivery carrier for improved anticancer therapy

Abstract

Theranostic nanoparticles with multifunctional ability have been emerging as a new platform for biomedical applications such as imaging, sensing and drug delivery. Despite gold nanorods (Au NRs) being an excellent nanosource with multifunctional versatility, they have certain limitations in biomedical applications, which include surfactant toxicity, biological stability and controlled drug release kinetics. Herein, we have developed Au NR-doxorubicin conjugates (DOX@PSS-Au NR) with improved drug loading efficiency (55 AE 6%) and minimum CTAB toxicity, by employing Au NRs (4.4 AE 0.5 aspect ratio) coated with poly(sodium 4-styrenesulfonate) (PSS). DOX@PSS-Au NR conjugates exhibited higher biological stability with sustained drug release kinetics at pH 5. The binding events of DOX molecules onto the PSS coated gold nanorods (PSS-Au NRs) were monitored through fluorescence quenching and the longitudinal surface plasmon resonance signals. Furthermore the anti-cancer potential and apoptosis inducing efficiency of DOX@PSS-Au NR conjugates in MCF-7 cells revealed higher therapeutic efficiency than free DOX, as corroborated through morphological assessment and in vitro cytotoxicity assay. In addition, DOX@PSS-Au NR conjugates showed efficient cellular entry and uniform intracellular distribution, suggesting the augmenting effect of chemotherapeutic drugs by Au NRs. Thus DOX@PSS-Au NR conjugates demonstrate significant therapeutic potential, suggesting their potential in anticancer therapy.

Synthesis and characterization of a multifunctional gold-doxorubicin nanoparticle system for pH triggered intracellular anticancer drug release

“…3a shows the UV-Vis absorption spectra of AuNPs, Au-PEG, Au-PEG-PAMAM and Au-PEG-PAMAM-DOX respectively. The red shift in the absorbance peak of gold nanoparticles observed has been widely attributed to a slight change in the refractive index of the local environment of AuNPs manifesting itself as a red shift in the absorbance spectrum [39]. As shown in Fig.…”

Ultrasound‐Propelled Nanoporous Gold Wire for Efficient Drug Loading and Release

“…The polyelectrolytes were coated onto the nanomotor surface by immersing a batch of the nanomotors (from a single membrane template) into 1 mL of the PSS or PAA solutions (2 mg/mL polyelectrolyte in 6 m m NaCl) for 3 h followed by washing three times with water. The conjugation between PSS and DOX proceeds not only via electrostatic interaction between the negatively‐charged sulfonate group of PSS and positively‐charged amine group of DOX, but may involve additional hydrogen bonding between the amino and hydroxyl groups of DOX and the sulfonate group of PSS . Similarly, electrostatic interactions have been used for attaching the cationic DOX to the anionic PAA films .…”

Localized sequence-specific release of a chemopreventive agent and an anticancer drug in a time-controllable manner to enhance therapeutic efficacy

“…At high concentrations of DOX within HMs, the fluorescence signal of DOX is quenched; upon release through the shells, its fluorescence intensity increases significantly [39,40]. In the absence of a stimulus by HFMF, the local fluorescence intensity of DOX in the skin that received Lipos-HMs remained constant for a period of 24 h, suggesting that the diffusion of DOX through the PLGA shells of the HMs was rather slow.…”