Bovine Serum Albumin-Conjugated Red Emissive Gold Nanocluster as a Fluorescent Nanoprobe for Super-resolution Microscopy

Abstract

The gold nanocluster (GNC), because of its interesting photoluminescence properties and easy renal clearance from the body, has tremendous biomedical applications. Unfortunately, it has never been explored for super-resolution microscopy (SRM). Here, we present a protein-conjugated red emissive GNC for super-resolution radial fluctuation (SRRF) of the lysosome in HeLa cells. The diameter of the lysosome obtained in SRRF is ∼59 nm, which is very close to the original diameter of the smallest lysosome in HeLa cells. Conjugation of protein to GNC aided in the specific labeling of the lysosome. We hope that GNC not only will replace some of the common dyes used in SRM but due to its electron beam contrast could also be used as a multimodal probe for several other correlative bioimaging techniques.

Fluorescent Probes for Super-Resolution Microscopy of Lysosomes

“…A recent publication by Yadav et al has also efficaciously contributed in the field of SRM imaging of lysosomes ( Table 1 and Table 2 ). 30 They developed bovine serum albumin (BSA) coated gold nanoclusters for specific labeling of lysosomes. Gold nanoclusters are well-known for their interesting photoluminescent properties and easy renal clearance from the body.…”

“…(e–h) Resolutions attained from SRRF microscopy of various lysosomes present in panel d (shown as 1–4, respectively). Reprinted with permission from ref ( 30 ). Copyright 2018.…”

Optically coupled gold nanostructures: plasmon enhanced luminescence from gold nanorod-nanocluster hybrids

“…bioimaging, drug delivery, sensing). [12][13][14][15][16][17] Their biocompatibility, "green" synthesis, photostability, and tunable near-infrared (NIR) photoluminescence (PL) with a large Stokes shift 18 makes AuNCs a valuable alternative to conventional semiconductor quantum dots. 3,8,[19][20][21] However, the PL quantum yield of AuNCs is relatively low (usually between 1% and 10%) and depends on the surface ligands used.…”

Super-Resolution Microscopy Revealed the Lysosomal Expansion During Epigallocatechin Gallate-Mediated Apoptosis

“…The radiality distribution is independent of the PSF intensity and the fwhm of this distribution and can be adjusted with the gradient convergence radius. As a result, SRRF provides a background-free super-resolved structure of the cellular organelle. , The size of the lysosomes ranges between 50 nm and 1 μm . Using cyanine-3-tagged BSA, we were able to get super-resolution images of the lysosomes with greater ease during the treatment of the cells with BSA-conjugated EGCG.…”

“…38,39 The size of the lysosomes ranges between 50 nm and 1 μm. 40 Using cyanine-3-tagged BSA, we were able to get super-resolution images of the lysosomes with greater ease during the treatment of the cells with BSA-conjugated EGCG. Figure 6a−d shows the transmission detection (TD), TIRF, and the corresponding super-resolution images of the cells stained with BSA-Cy3.…”