Depth‐Resolved Enhanced Spectral‐Domain OCT Imaging of Live Mammalian Embryos Using Gold Nanoparticles as Contrast Agent

Abstract

High‐resolution and real‐time visualization of the morphological changes during embryonic development are critical for studying congenital anomalies. Optical coherence tomography (OCT) has been used to investigate the process of embryogenesis. However, the structural visibility of the embryo is decreased with the depth due to signal roll‐off and high light scattering. To overcome these obstacles, in this study, combined is a spectral‐domain OCT (SD‐OCT) with gold nanorods (GNRs) for 2D/3D imaging of live mouse embryos. Inductively coupled plasma mass spectrometry is used to confirm that GNRs can be effectively delivered to the embryos during ex vivo culture. OCT signal, image contrast, and penetration depth are all enhanced on the embryos with GNRs. These results show that after GNR treatment, more accurate spatial localization and better contrasting of the borders among organs can be observed on E9.5 and E10.5 mouse embryos. Furthermore, the strong optical absorbance of GNRs results in much clearer 3D images of the embryos, which can be used for calculating the heart areas and volumes of E9.5 and E10.5 embryos. These findings provide a promising strategy for monitoring organ development and detecting congenital structural abnormalities in mice.

Nonspherical Metal‐Based Nanoarchitectures: Synthesis and Impact of Size, Shape, and Composition on Their Biological Activity

“…Reproduced with permission. [ 30 ] Copyright 2019, Wiley. F) ZnO nanostars synthesized by hydrothermal method.…”

“…Seed‐mediated growth is the most often deployed two‐step approach for synthesizing monodispersed Au nanorods in the biomedicine field. [ 30,57–59 ] Gold seeds are first prepared in a seed solution containing cetyltrimethylammoniumbromide (CTAB) cationic surfactant, through reduction of Au 3+ by NaBH 4 . Further reduction of Au 3+ to Au + is achieved by addition of ascorbic acid (a weak reductant) to the growth solution.…”

Green preparation of anti-inflammation an injectable 3D porous hydrogel for speeding up deep second-degree scald wound healing

“…All the experiments were conducted on a home-built OCT system. 36 The skin of male SD rats was placed in a photosensitive polymer 3D-printed groove module to reduce the effect of micromotion. It was then xed on an X-Y-Z adjusting platform for the easy adjustment during imaging.…”

The Impact of Surface Chemistry on Gold Nanorods Uptake in Stem Cell-derived Therapeutic Cells

“…Gold nanoparticles (AuNPs) are of particular interest for OCT because they have strong localized surface plasmon resonance (LSPR) for interaction with light 44 and can be tuned towards the NIR-I and NIR-II windows. [45][46] Studies show that the size and shape of AuNPs, nanospheres, [47][48] nanocages, nanoshells, [49][50][51] nanobipyramids, 40 branched AuNPs, 52 nanoprisms, 53 nanorods, [54][55][56][57][58][59] and nanodisks, 60 have high scattering efficiencies and OCT contrast when the SPR band is within the central operating wavelength of the OCT. [61][62] Silver nanoparticles (AgNPs), 63 silica-coated gold nanostars, 64 silica-coated silver nanorods (AgNRs), [65][66] and titanium oxide (TiO2) 67 also have high scattering efficiencies. For cell labeling studies nanomaterials such as quantum dots, 68 luminescent nanoparticles, 69 iron oxide nanoparticles, 70 , and AuNPs [71][72] have been employed as they produce intense signal sensitivity to detect a low number of cells with a distinct advantage over reporter genes.…”