Bovine serum albumin template synthesis of fluorescent gold nanoclusters for nitric oxide detection in vitro

Abstract

Bovine serum albumin (BSA) stabilised gold nanoclusters (Au NCs) were prepared and used for nitric oxide (NO) detection in vitro. The prepared BSA-Au NCs with an average diameter of 1.5 nm emitted strong red photoluminescence (PL), accompanied with the maximum emission peak at 640 nm. Furthermore, the BSA-Au NCs were developed as a PL probe for NO detection in vitro.Owing to the damage of BSA-Au NCs structure caused by the interaction between NO and BSA, the PL intensity of BSA-Au NCs regularly reduced with the increase in NO concentration [NO]. There is a proportional relationship between the PL intensity of BSA-Au NCs and the [NO] (0.05-0.35 mM), together with a detection limit of 0.017 mM. Experimental results confirmed high selectivity and sensitivity of the NO probe over other reactive oxygen and nitrogen species, and presented excellent detection capacity in aqueous model samples.

Low-Triggering-Potential Single-Color Electrochemiluminescence from Bovine Serum Albumin-Stabilized Unary Au Nanocrystals for Immunoassays

“…The fourier-transform infrared (FTIR) spectrum (Figure S2B) fails to exhibit a significant difference between BSA and BSA−AuNCs, indicating that embedded Au elements within BSA−AuNCs cannot affect the structure of BSA. 35 X-ray photoelectron spectroscopy (XPS) spectra further prove that the BSA− AuNCs contain O, S, N, and C elements (Figure S3) and Au element (Figure 1D). 36 All these data prove the successful synthesis of BSA−AuNCs.…”

“…The element mapping patterns show that Au, O, S, C, and N elements are uniformly distributed within the BSA–AuNCs (Figure S1). According to Figure S2A, the X-ray diffraction (XRD) pattern of BSA–AuNCs is highly similar to that of BSA, indicating that both AuNCs and BSA are amorphous, and BSA–AuNCs are typically noncrystalline . The sharp peaks in the XRD pattern of BSA–AuNCs can be referred to as NaCl (JCPDS: 05-0628), which might be related to the introduction of NaOH and HCl in the purification process.…”

“…According to Figure A, BSA–AuNCs not only exhibit an obvious UV–vis absorption peak around 275 nm, which can be referred to as BSA, but also demonstrates bright-red PL with a maximum emission wavelength around 660 nm. The high-resolution transmission electron microscopy (HRTEM) pattern exhibits that the BSA–AuNCs are of spherical morphology and monodispersed with a uniform diameter of around 5 nm (Figure B).…”

“…According to Figure S2A, the X-ray diffraction (XRD) pattern of BSA−AuNCs is highly similar to that of BSA, indicating that both AuNCs and BSA are amorphous, and BSA−AuNCs are typically noncrystalline. 35 The sharp peaks in the XRD pattern of BSA−AuNCs can be referred to as NaCl (JCPDS: 05-0628), which might be related to the introduction of NaOH and HCl in the purification process. The fourier-transform infrared (FTIR) spectrum (Figure S2B) fails to exhibit a significant difference between BSA and BSA−AuNCs, indicating that embedded Au elements within BSA−AuNCs cannot affect the structure of BSA.…”

NIR‐Emitting Gold Nanoclusters–Modified Gelatin Nanoparticles as a Bioimaging Agent in Tissue

“…Glutathione has been extensively used for AuNC synthesis due to the strong affinity of the thiol group to form AuS bond . Cysteine‐containing proteins such as bovine serum albumin, insulin, trypsin, and lysozyme have been also explored for the same purpose. Other studies have also shown that basic amino acids together with tyrosine and tryptophan can contribute to the reduction of the ions to metallic gold .…”