Molecular Imaging of Infarcted Heart by Biofunctionalized Gold Nanoshells

Abstract

The unique combination of physical and optical properties of silica (core)/gold (shell) nanoparticles (gold nanoshells) makes them especially suitable for biomedicine. Gold Nanoshells have been used from high-resolution in vivo imaging to in vivo photothermal tumor treatment. Furthermore, the reduced size and large scattering cross section of Gold Nanoshells in the second biological window (1000-1700 nm) make them also especially adequate for molecular optical coherence tomography (OCT). In this work, we demonstrate how, after adequate functionalization, gold nanoshells in combination with clinical OCT systems are capable of imaging damage in the myocardium after an infarct. Since both inflammation and apoptosis are two of the main mechanisms underlying myocardial damage after ischemia, such damage imaging is achieved by endowing Gold Nanoshells with selective affinity for the inflammatory marker Intercellular Adhesion Molecule 1 (ICAM-1), and the apoptotic marker phosphatidylserine (PS). The results here presented constitute a first step towards a fast, safe, and accurate diagnosis of damaged tissue within infarcted hearts at the molecular level by means of the highly sensitive OCT interferometric technique.

Bismuth Selenide Nanostructured Clusters as Optical Coherence Tomography Contrast Agents: Beyond Gold-Based Particles

“… 17 − 20 Among them, plasmonic nanoparticles made of gold are the staple, owing to the strong photon scattering featured by these contrast agents at the probing wavelength used in commercially available OCT instruments—mainly falling in the near-infrared (NIR) range. As a result, gold-based plasmonic nanoparticles such as gold nanoshells (GNSs) 21 − 23 and gold nanorods 24 − 26 are generally employed as positive contrast agents in OCT studies, with GNSs providing the highest contrast in OCT scans. 27 , 28 However, their synthesis is labor- and time-intensive, entailing successive steps of SiO 2 core growth and coating with gold layers.…”

“…To increase the imaging potential of OCT, several contrast agents have been proposed. − Among them, plasmonic nanoparticles made of gold are the staple, owing to the strong photon scattering featured by these contrast agents at the probing wavelength used in commercially available OCT instrumentsmainly falling in the near-infrared (NIR) range. As a result, gold-based plasmonic nanoparticles such as gold nanoshells (GNSs) − and gold nanorods − are generally employed as positive contrast agents in OCT studies, with GNSs providing the highest contrast in OCT scans. , However, their synthesis is labor- and time-intensive, entailing successive steps of SiO 2 core growth and coating with gold layers. The expensiveness of noble metals is another shortcoming of these contrast agents, making other nanosystems that could be produced in a shorter time and with reduced costs highly desirable.…”

Controlled nano-agglomerates as stabile SERS reporters for unequivocal labelling

“…Nanosystems has been widely developed in sensor devices for diagnostics, in vitro and in vivo diagnosis 1 . This diagnosis field takes benefits from the design and synthesis of nanomaterials 2 – 4 , especially noble metal nanomaterials showing localized surface plasmon resonance (LSPR) properties. This LSPR phenomenon limits nanomaterials absorbing specific region of light, and makes the nanomaterials sensitive to the modifications of physical properties of nanomaterials and their environments showing plasmonic absorption shifts 5 – 7 .…”

PEGylated Indium Nanoparticles: A Metallic Contrast Agent for Multiwavelength Photoacoustic Imaging and Second Near-Infrared Photothermal Therapy

“…Localized surface plasmon resonances (LSPR) in metallic nanoparticles, the collective electron oscillations by the incoming electromagnetic field, enable huge heat generation during light–matter interactions, thus depicting remarkable advancements for photoacoustic imaging and photothermal therapy (PTT) of malignant tumors. , Until now, most of the reported LSPR metals for PTT are noble metals, such as gold (Au) and palladium (Pd), due to their high charge carrier density and favorable bulk dielectric properties. − However, expensive noble metal nanoparticles usually possess remarkable optical absorption only in the first near-infrared (NIR-I) biowindow (700–950 nm), presenting limited tissue-penetration depth compared to the second near-infrared (NIR-II) biowindow (1000–1700 nm). , Additionally, although noble metal nanoparticles are generally proven to be biocompatible in preclinical studies, their real toxicity in the clinic is still unknown. , In this regard, exploration of NIR-II metal nanoparticles as a low-cost and biosafe alternative to conventional noble metals is of significance.…”

“…6,7 Additionally, although noble metal nanoparticles are generally proven to be biocompatible in preclinical studies, their real toxicity in the clinic is still unknown. 8,9 In this regard, exploration of NIR-II metal nanoparticles as a low-cost and biosafe alternative to conventional noble metals is of significance.…”