Synthesis of Yellow-Fluorescent Carbon Nano-dots by Microplasma for Imaging and Photocatalytic Inactivation of Cancer Cells

In recent years, multifunctional nanoparticles with combined diagnostic and therapeutic functions show great promise in nanomedicine. In this study, we report the environmentally friendly synthesis of fluorescent carbon nano-dots such as carbon quantum dots (CQDs) by microplasma using o-phenylenediamine. The produced CQDs exhibited a wide absorption peaks at 380–500 nm and emitted bright yellow fluorescence with a peak at 550 nm. The CQDs were rapidly taken up by HeLa cancer cells. When excited under blue light, a bright yellow fluorescence signal and intense reactive oxygen species (ROS) were efficiently produced, enabling simultaneous fluorescent cancer cell imaging and photodynamic inactivation, with a 40% decrease in relative cell viability. Furthermore, about 98% cells were active after the incubation with 400 μg mL−1 CQDs in the dark, which revealed the excellent biocompatibility of CQDs. Hence, the newly prepared CQDs are thus demonstrated to be materials which might be effective and safe to use for in vivo bioimaging and imaging-guided cancer therapy.

Boron-doped and serine and histidine-functionalized graphene quantum dot with strong yellow fluorescence emission for highly sensitive detection of carbofuran in cucumber and cabbage

Weak fluorescence at visible light excitation limits many applications of graphene quantum dots. The paper reports synthesis of boron-doped and serine and histidine-functionalized graphene quantum dot (B-Ser-His-GQD). The resulting B-Ser-His-GQD...

Fluorescence assay for sensitive detection of fipronil based on the " on-off " oxidized SWCNHs/aptamer sensor

A simple, quick and effective turn-on fluorescence assay was built up for determination of fipronil (FIP) based on yellow fluorescence of FAM-aptamer and an excellent quenching capability of the oxidized...

A Novel Fluorescent Test Papers Based on Carbon Dots for Selective and Sensitive Detection of Cr (VI)

In recent years, carbon dots (CDs) are promising fluorescence probes for ions detection. In this paper, the CDs which are with an average diameter of 5.5 nm were synthesized through a simple one-step hydrothermal carbonization of ethylene diamine tetraacetic acid (EDTA) salt. The CDs have strong yellow photoluminescence (PL) with a maximum emission intensity at 550 nm under an excitation wavelength of 450 nm. As the electron transfer will occur between Cr (VI) and the CDs, yellow fluorescence was quenched after adding the Cr (VI) ions. The CDs probe allows the detection of Cr (VI) ions over a concentration range from 0 to 0.1 M (R2 = 0.987) and the lower detection limit is 10−5 M. Simultaneously, the CDs show highly selectivity and stability toward the detection of Cr (VI) ions.

Green Synthesis of Yellow-fluorescent Carbon Nano-Dots for Cancer-Cell Image and Photocatalytic Inactivation by Using Microplasma

In recent years, multifunctional nanoparticles with combined diagnostic and therapeutic functions show great promise in nanomedicine. In this work, we report the environmentally friendly synthesis of fluorescent carbon nano-dots such as carbon quantum dots (CQDs) by microplasma using o-phenylenediamine. The produced CQDs exhibited a wide absorption peaks at 380-500 nm and emitted bright yellow fluorescence with a peak at 550 nm. The CQDs were rapidly taken up by HeLa cancer cells. When excited under blue light, a bright yellow fluorescence signal and intense reactive oxygen species (ROS) were efficiently produced, enabling simultaneous fluorescent cancer cell imaging and photodynamic inactivation, with a 40% decrease in relative cell viability. Furthermore, the CQDs has 98% cell viability at concentrations of 400 μg·mL-1 in the dark demonstrating excellent biocompatibility. The newlyprepared CQDs are thus demonstrated to be materials that can be effectively for imaging-guided cancer therapy.

A Fluorescent Polyurethane with Covalently Cross-Linked Rhodamine Derivatives

Rhodamine derivatives (RDs) with three reactive hydrogens were synthesized and well characterized by Fourier transform infra-red spectroscopy (FTIR), 1H nuclear magnetic resonance (1H NMR) and electrospray ionization mass spectra (ESI mass). Then, the obtained RD was covalently cross-linked into polyurethane (PU) matrix through chemical linkages to fabricate a network structure, and the fluorescent properties, mechanical properties, thermal stability, and emulsion particle size were systematically investigated. Results demonstrate that PU-RD maintains initial fluorescent properties and emits desirable yellow fluorescence under ultraviolet irradiation. Moreover, compared with linear PU without fluorescers, PU-RD shows clearly improved mechanical properties and thermal stability, on account of the formed network structures.

A novel sensor for sequential and cellular detection of copper and lactic acid

<div> <p>We report self assembling/aggregation properties of acyl-thiourea derivative, N-((6-methoxy-pyridin-2-yl)carbamothioyl)benzamide<a>(<b>NG1</b>) </a><a>[i1]</a> and the disaggregation induced emission which leads to its application as fluorescence and colorimetric probe for the sensitive detection of Cu²⁺. The microscopy analysis of <b>NG1</b>via SEM, and AFM reveal that it self-assembles to give fiber-like morphologies.Interestingly,<b>NG1</b> also assembles to fluorescent fibers which show tunable emission properties. Addition of Cu²⁺to these fibers causedisruption/disaggregation of fibers and a golden yellow fluorescence is produced due to disaggregation induced emission enhancement (DIEE). The application of <b>NG1</b> as selective sensor for copper was further assessed by UV visible and fluorescence spectroscopy. Limit of Detection(LOD) of Cu²⁺with colorimetry was 2.5ppm while LOD of Cu²⁺ with fluorescence was as low as 0.1ppm. This yellow fluorescence is quenched after the addition of lactic acid and hence <b>NG1</b> could potentially be used for the sequential detection of both Cu and lactate.Further, structural modification of the probe <b>NG1</b> suggest crucial role of both pyridine and acyl-thiourea moiety in the binding of Cu²⁺. The experimental results of interaction of <b>NG1</b> with Cu²⁺ and lactate were also validated theoretically by quantum chemical calculations based on density functional theory (DFT). Finally, we explore the ability of <b>NG1</b>for the sequential detection of Cu²⁺ and lactate in cells, which suggests<b>NG1</b> can be used effectively for the cellular imaging applications and to selectively sense Cu²⁺. To, the best of our knowledge,</p></div> <p>this is the first report wherein a dual sensor for Cu²⁺and lactate ion is synthesized and it may in allpossibilities pave the way for the diagnosis of Cu²⁺associated disorders like Wilson’s disease and in the detection of elevated lactate levels which are associated with the wide range of pathologies likemitochondrial diseases, cerebral ischemia and cancer.<b></b></p> <div> </div><br>

A novel sensor for sequential and cellular detection of copper and lactic acid

<div> <p>We report self assembling/aggregation properties of acyl-thiourea derivative, N-((6-methoxy-pyridin-2-yl)carbamothioyl)benzamide<a>(<b>NG1</b>) </a><a>[i1]</a> and the disaggregation induced emission which leads to its application as fluorescence and colorimetric probe for the sensitive detection of Cu²⁺. The microscopy analysis of <b>NG1</b>via SEM, and AFM reveal that it self-assembles to give fiber-like morphologies.Interestingly,<b>NG1</b> also assembles to fluorescent fibers which show tunable emission properties. Addition of Cu²⁺to these fibers causedisruption/disaggregation of fibers and a golden yellow fluorescence is produced due to disaggregation induced emission enhancement (DIEE). The application of <b>NG1</b> as selective sensor for copper was further assessed by UV visible and fluorescence spectroscopy. Limit of Detection(LOD) of Cu²⁺with colorimetry was 2.5ppm while LOD of Cu²⁺ with fluorescence was as low as 0.1ppm. This yellow fluorescence is quenched after the addition of lactic acid and hence <b>NG1</b> could potentially be used for the sequential detection of both Cu and lactate.Further, structural modification of the probe <b>NG1</b> suggest crucial role of both pyridine and acyl-thiourea moiety in the binding of Cu²⁺. The experimental results of interaction of <b>NG1</b> with Cu²⁺ and lactate were also validated theoretically by quantum chemical calculations based on density functional theory (DFT). Finally, we explore the ability of <b>NG1</b>for the sequential detection of Cu²⁺ and lactate in cells, which suggests<b>NG1</b> can be used effectively for the cellular imaging applications and to selectively sense Cu²⁺. To, the best of our knowledge,</p></div> <p>this is the first report wherein a dual sensor for Cu²⁺and lactate ion is synthesized and it may in allpossibilities pave the way for the diagnosis of Cu²⁺associated disorders like Wilson’s disease and in the detection of elevated lactate levels which are associated with the wide range of pathologies likemitochondrial diseases, cerebral ischemia and cancer.<b></b></p> <div> </div><br>