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1.
J Proteome Res ; 23(5): 1713-1724, 2024 May 03.
Article in English | MEDLINE | ID: mdl-38648079

ABSTRACT

Non-small-cell lung cancer (NSCLC), a common malignant tumor, requires deeper pathogenesis investigation. Autophagy is an evolutionarily conserved lysosomal degradation process that is frequently blocked during cancer progression. It is an urgent need to determine the novel autophagy-associated regulators in NSCLC. Here, we found that pirin was upregulated in NSCLC, and its expression was positively correlated with poor prognosis. Overexpression of pirin inhibited autophagy and promoted NSCLC proliferation. We then performed data-independent acquisition-based quantitative proteomics to identify the differentially expressed proteins (DEPs) in pirin-overexpression (OE) or pirin-knockdown (KD) cells. Among the pirin-regulated DEPs, ornithine decarboxylase 1 (ODC1) was downregulated in pirin-KD cells while upregulated along with pirin overexpression. ODC1 depletion reversed the pirin-induced autophagy inhibition and pro-proliferation effect in A549 and H460 cells. Immunohistochemistry showed that ODC1 was highly expressed in NSCLC cancer tissues and positively related with pirin. Notably, NSCLC patients with pirinhigh/ODC1high had a higher risk in terms of overall survival. In summary, we identified pirin and ODC1 as a novel cluster of prognostic biomarkers for NSCLC and highlighted the potential oncogenic role of the pirin/ODC1/autophagy axis in this cancer type. Targeting this pathway represents a possible therapeutic approach to treat NSCLC.


Subject(s)
Autophagy , Carcinoma, Non-Small-Cell Lung , Cell Proliferation , Disease Progression , Lung Neoplasms , Ornithine Decarboxylase , Female , Humans , Male , A549 Cells , Autophagy/genetics , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Non-Small-Cell Lung/metabolism , Cell Line, Tumor , Cell Proliferation/genetics , Gene Expression Regulation, Neoplastic , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Lung Neoplasms/metabolism , Ornithine Decarboxylase/metabolism , Ornithine Decarboxylase/genetics , Prognosis , Up-Regulation
2.
Microb Pathog ; 173(Pt A): 105837, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36257566

ABSTRACT

Gamma-proteobacteria is a class of gram-negative opportunistic pathogens existing in the intestinal flora, often leading to diarrhea and intestinal infectious diseases, and plays an important role in maintaining intestinal homeostasis. Type III secretion system (T3SS), an important virulence system, is closely related to the adhesion and invasion and pathogenicity to host cells. Therefore, anti-virulence agents targeting T3SS are important strategies for controlling pathogenic infections. In this study, the anti-Salmonella T3SS active compounds neochebulagic acid (1), ellagic acid (2) and urolithin M5 (3) were isolated from seed extract of Terminalia citrina by activity-guided isolation method. Based on the fact that urolithins are the main and stable intestinal microbiota metabolites of hydrolysable tannins, we found that the metabolite urolithin B repressed translation and secretion of SipC through the Hha-H-NS-HilD-HilC-RtsA-HilA regulatory pathway. The results provide evidence for Terminalia seeds and ellagitannin-rich berries and nuts in regulating intestinal homeostasis and treating bacterial infection.


Subject(s)
Terminalia , Type III Secretion Systems , Type III Secretion Systems/metabolism , Gene Expression Regulation, Bacterial , Salmonella typhimurium , Hydrolyzable Tannins/pharmacology , Hydrolyzable Tannins/metabolism , Transcription Factors/genetics , Bacterial Proteins/genetics
3.
FEMS Microbiol Lett ; 369(1)2022 08 08.
Article in English | MEDLINE | ID: mdl-35798014

ABSTRACT

Chlorogenic acid (CGA), one of the most abundant polyphenols in the human diet, exhibits many biological properties, including antibacterial properties. Numerous studies have investigated the antibacterial effects of CGA, however, the molecular mechanisms governing its effects against Streptococcus pyogenes have not been fully elucidated. Streptococcus pyogenes is a Gram-positive pathogen that causes a wide range of human infections and postinfectious immune-mediated disorders. In this study, we used an isobaric tagging for relative and absolute quantitation (iTRAQ)-based proteomic technique to investigate the underlying mode of action of CGA against S. pyogenes. KEGG and GO analyses indicated that CGA affected the expression of protein alterations involved in multiple pathways, downregulating the expression of ribosomal proteins, and upregulating the expression of proteins associated with fatty acid metabolism, pyruvate metabolism, and propanoate metabolism, while activating the expression of oxidation-reduction-related proteins. Moreover, further cell-based experiments verified that CGA scavenges intracellular ROS in S. pyogenes. These results suggest that CGA may exert its antibacterial action through several actions, such as downregulating ribosomal subunits, affecting lipid metabolism, and scavenging intracellular ROS. The results of this study may help to elucidate the molecular mechanisms by which CGA combats pathogens.


Subject(s)
Chlorogenic Acid , Lipid Metabolism , Anti-Bacterial Agents/pharmacology , Chlorogenic Acid/pharmacology , Humans , Proteomics , Reactive Oxygen Species/metabolism , Streptococcus pyogenes/metabolism
4.
Phytochemistry ; 192: 112929, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34481176

ABSTRACT

From the aerial extracts of Coptosapelta diffusa (Champ. ex Benth.) Steenis, twenty-one compounds were isolated and identified by means of column chromatography and NMR and MS techniques, respectively. Amongst, ten ones were determined to be undescribed compounds including six seco-iridoid glucosides (1-6), 2-(hydroxymethyl)-1,2,3,4-tetrahydroanthracene-9,10-dione (7) and three guaiane-type sesquiterpenes (15-17). Compounds 7, 8 and 9 exhibited inhibitory activities against Staphylococcus aureus ATCC25923 with MIC of 8, 4 and 8 µg/mL. The use of 1-6 (iridoids), 7-14 (anthraquinones) and 15-17 (sesquiterpenes) as chemotaxonomic markers for this species was evidenced. Structurally, 7-14 are similar to those anthraquinones isolated from other species of the family Rubiaceae, confirming their close phylogenetic relationship. Whereas, these iridoids and sesquiterpenes with unique structures provided chemotaxonomic evidence to support the genus Coptosapelta (the tribe Coptosapelteae) as a sister of the subfamily Rubioideae. These results contrast with the general producing tendency of indole alkaloids by the species of the subfamily Cinchonoideae, and merit chemotaxonomic significance for the delimitation of Coptosapelta.


Subject(s)
Rubiaceae , Anthraquinones , Iridoid Glucosides , Iridoids , Phylogeny , Plant Extracts
5.
Am J Cancer Res ; 11(7): 3575-3593, 2021.
Article in English | MEDLINE | ID: mdl-34354861

ABSTRACT

Human hepatocellular carcinoma (HCC) is the most frequent cancer worldwide with a poor prognosis. Tumor-specific pyruvate kinase M2 (PKM2) is essential for cancer metabolism and tumorigenesis. Shikonin, a specific inhibitor of PKM2, but not PKM1, exhibits significant anticancer effect in HCC, and was deemed as a promising drug for cancer therapy. However, shikonin-mediated bypass signaling in HCC remained unclear. Here, we performed forward/reverse stable isotope labeling with amino acids in cell culture (SILAC)-based proteomics to identify the early molecular events controlled by shikonin. We demonstrated for the first time that shikonin could induce the nuclear translocation of PKM2 for recruiting Nrf2, and transcriptionally activated Nrf2 downstream target gene BAG3, therefore increasing protective effect to sustain cell survival. Knockdown of BAG3 by si-RNA significantly potentiated the anticancer effect of shikonin. These findings provided the first evidence of a new noncanonical function of inhibited PKM2 could act as a transcriptional coactivator of Nrf2 in cancer survival, highlight that shikonin in combined with BAG3 inhibitor could be a promising therapeutic strategy for HCC therapy.

6.
Chin J Nat Med ; 19(7): 536-539, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34247777

ABSTRACT

Over-expression of the pathway specific positive regulator gene is an effective way to activate silent gene cluster. In the curret study, the SARP family regulatory gene, vasR2, was over-expressed in strain Verrucosispora sp. NS0172 and the cryptic gene cluster responsible for the biosynthesis of pentaketide ansamycin was partially activated. Two tetraketides (1 and 2) and a triketide (3) ansamycins, together with five known compounds (4-8), were isolated and elucidated from strain NS0172OEvasR2. Their NMR data were completely assigned by analysis of their HR-ESI-MS and 1H, 13C NMR, HMQC, HMBC and 1H-1H COSY spectra.


Subject(s)
Micromonosporaceae , Polyketides , Rifabutin/metabolism , Micromonosporaceae/genetics , Micromonosporaceae/metabolism , Multigene Family , Polyketides/metabolism
7.
MedComm (2020) ; 2(4): 810-820, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34977878

ABSTRACT

Lung adenocarcinoma (LAC) is one of the most common pulmonary adenocarcinomas with a high peak of mortality, and metastasis is the main culprit of LAC deaths. microRNAs play important role in cancer metastasis, and thus are regarded as potential diagnostic and prognostic markers for human cancers. However, many miRNAs exhibit dual roles in diverse cellular contexts. Here, we revealed that hsa-miR-335, a previously reported tumor suppressor, exhibited an oncogenic role in LAC. Overexpression of miR-335 enhanced the abilities of A549 and H1299 cells to invade and migrate by regulating epithelial-mesenchymal transition, while inhibition of miR-335 exhibited an opposite effect in vitro and in vivo. Mechanically, miR-335 inhibited the expression of Copine-1 (CPNE1), an NF-κB suppressor, through interacting with its mRNA 3'UTR, while mutating the binding sites abolished this inhibitory effect. This finding not only highlights the suppressive effect of CPNE1 on cell motility, but also provides new insight into miR-335 in promoting LAC metastasis.

8.
Bioorg Med Chem ; 29: 115868, 2021 01 01.
Article in English | MEDLINE | ID: mdl-33191085

ABSTRACT

Unlike other DNA topoisomerase II (topo II) inhibitors, our recently identified acridone derivative E17 exerted strong cytotoxic activity by inhibiting topo II without causing topo II degradation and DNA damage, which promoted us to explore more analogues of E17 by expanding its chemical diversification and enrich the structure-activity relationship (SAR) outcomes of acridone-oriented chemotypes. To achieve this goal, 42 novel acridone derivatives were synthesized and evaluated for their antiproliferative efficacies. SAR investigations revealed that orientation and spatial topology of R3 substituents make greater contributions to the bioactivity, exemplified by compounds E24, E25 and E27, which has provided valuable information for guiding further development of acridone derivatives as promising drug candidates.


Subject(s)
Acridones/pharmacology , Antineoplastic Agents/pharmacology , DNA Topoisomerases, Type II/metabolism , Topoisomerase II Inhibitors/pharmacology , Acridones/chemical synthesis , Acridones/chemistry , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Molecular Structure , Structure-Activity Relationship , Topoisomerase II Inhibitors/chemical synthesis , Topoisomerase II Inhibitors/chemistry , Tumor Cells, Cultured
9.
Chin J Nat Med ; 18(12): 952-956, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33357726

ABSTRACT

Constitutively expression of the pathway-specific activators is an effective method to activate silent gene clusters and improve natural product production. In this study, nine shunt products of aminoansamycins (1-9) were identified from a recombinant mutant strain S35-LAL by overexpressed the large-ATP-binding regulator of the LuxR family (LAL) gene aas1 in Streptomyces sp. S35. All the compounds showed no anti-microbial, anti-T3SS and cytotoxic activities.


Subject(s)
Biological Products/metabolism , Lactams, Macrocyclic/metabolism , Multigene Family , Streptomyces/genetics , Organisms, Genetically Modified , Streptomyces/metabolism
10.
J Am Chem Soc ; 142(36): 15276-15281, 2020 09 09.
Article in English | MEDLINE | ID: mdl-32815720

ABSTRACT

A highly branch- and enantioselective 1,4-enynes synthesis from readily available terminal alkynes and racemic allylic carbonates by Sonogashira type synergistic Rh and Cu catalysis under neutral conditions has been developed. Aliphatic and aromatic terminal alkynes with various functional groups could be used directly. An inner-sphere reductive elimination C(sp)-C(sp3) bond formation mechanism is supported by the stoichiometric reaction.

11.
Chem Commun (Camb) ; 56(55): 7609-7612, 2020 Jul 14.
Article in English | MEDLINE | ID: mdl-32515436

ABSTRACT

In this study, natural graphite was liquid exfoliated in the presence of single-layer carbon-based dots (CDs), which were used as intercalators. It was found that graphene of mainly single-layer has been obtained, on which lots of CDs were deposited. Combining the unique properties of these two materials, the CDs deposited on graphene (G/CDs) are proved to be outstanding catalysts for the electroreduction of oxygen to H2O2. The results from control experiments and density functional theory calculations demonstrated that the oxygen-containing functional groups on the CDs played a key role in the catalytic activity of the G/CDs.

12.
Nat Prod Res ; 34(15): 2219-2224, 2020 Aug.
Article in English | MEDLINE | ID: mdl-31184497

ABSTRACT

Strain HT88 was isolated from the fresh stems of Mallotus nudiflorus L, and it was identified as Nocardiopsis sp. by analyzing its morphology and the 16S rRNA sequence. The extracts of fermented HT88 showed potent antimicrobial activities. Bioassay guided separation of extracts led to eight proline (or hydroxyproline, Hyp)-containing cyclic dipeptides. Their structures were determined by 1D and 2D NMR spectroscopy and ESI mass spectrometry and further comparison with existing 1H and 13C NMR, melting points and specific rotation data. The eight 2,5-diketopiperazines (DKPs) were identified as cyclo(L-Pro-L-Leu) (1), cyclo(Pro-Leu) (2), cyclo(L-trans-Hyp-L-Leu) (3), cyclo(D-trans-Hyp-D-Leu) (4), and cyclo(D-Pro-L-Phe) (5), cyclo(L-Pro-L-Phe) (6), and cyclo(D-cis-Hyp-L-Phe) (7), cyclo(L-trans-Hyp-L-Phe) (8), respectively. Up to date, this is the first isolation of four pairs of proline based DKPs from Nocardiopsis sp.


Subject(s)
Dipeptides/isolation & purification , Mallotus Plant/microbiology , Nocardia/chemistry , Proline , Anti-Infective Agents/isolation & purification , Anti-Infective Agents/pharmacology , Diketopiperazines/chemistry , Diketopiperazines/isolation & purification , Dipeptides/chemistry , Dipeptides/pharmacology , Hydroxyproline , Microbial Sensitivity Tests , Peptides, Cyclic
13.
Biochem Biophys Res Commun ; 513(2): 313-318, 2019 05 28.
Article in English | MEDLINE | ID: mdl-30955862

ABSTRACT

Topo II inhibitors, e.g. etoposide, doxorubicin and mitoxantrone, etc., which exert their functions by trapping the covalent 'topo II-DNA cleavable complex' via intercalation into DNA base pairs, leading to DNA damage and degradation of topo II, and inducing decline of cell sensitivity and corresponding multidrug resistance (MDR). E17 is a recently identified topo II inhibitor in our lab which has validated to possess a strong topo II inhibitory activity on cell viability, colony formation, and cell migration. Especially, E17 can trigger G2/M cell cycle arrest through inhibiting chromosome condensation without causing obvious DNA damage in colorectal cancer (CRC) HCT116 cell. E17 can also induce the accumulation of topo II-DNA complex without leading to degradation of topo II, which was different from topo II inhibitors VP16 or ICRF-187, suggesting E17 might be a potential lead for further development by serving as a strong topo II inhibitor.


Subject(s)
Antineoplastic Agents/pharmacology , Chromosomes/drug effects , Colorectal Neoplasms/drug therapy , Topoisomerase II Inhibitors/pharmacology , Antineoplastic Agents/chemistry , Cell Cycle Checkpoints/drug effects , Cell Proliferation/drug effects , Cell Survival/drug effects , Chromosomes/metabolism , Chromosomes/ultrastructure , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/pathology , Drug Discovery , HCT116 Cells , HeLa Cells , Humans , Topoisomerase II Inhibitors/chemistry
14.
Adv Sci (Weinh) ; 5(12): 1801201, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30581711

ABSTRACT

The exploitation of smart nanoagents based drug delivery systems (DDSs) has proven to be a promising strategy for fighting cancers. Hitherto, such nanoagents still face challenges associated with their complicated synthesis, insufficient drug release in tumors, and low cancer cell chemosensitivity. Here, the engineering of an adenosine triphosphate (ATP)-activatable nanoagent is demonstrated based on self-assembled quantum dots-phenolic nanoclusters to circumvent such challenges. The smart nanoagent constructed through a one-step assembly not only has high drug loading and low cytotoxicity to normal cells, but also enables ATP-activated disassembly and controlled drug delivery in cancer cells. Particularly, the nanoagent can induce cell ATP depletion and increase cell chemosensitivity for significantly enhanced cancer chemotherapy. Systematic in vitro and in vivo studies further reveal the capabilities of the nanoagent for intracellular ATP imaging, high tumor accumulation, and eventual body clearance. As a result, the presented multifunctional smart nanoagent shows enhanced antitumor efficacy by simultaneous ATP-responsive chemodrug release and cancer cell sensitization. These findings offer new insights toward the design of smart nanoagents for improved cancer therapeutics.

15.
ACS Appl Mater Interfaces ; 10(41): 35495-35502, 2018 Oct 17.
Article in English | MEDLINE | ID: mdl-30251823

ABSTRACT

Black phosphorus (BP) nanosheets with unique biocompatibility and superior optical performance have attracted enormous attention in material science. However, their instability and poor solution-processability severely limit their clinical applications. In this work, we demonstrate the use of silk fibroin (SF) as an exfoliating agent to produce thin-layer BP nanosheets with long-term stability and facile solution-processability. Presence of SF prevents rapid oxidation and degradation of the resultant BP nanosheets, enhancing their performance in physiological environment. The SF-modified BP nanosheets exhibit subtle solution-processability and are fabricated into various BP-based material formats. As superior photothermal agents, BP-based wound dressings effectively prevent bacterial infection and promote wound repair. Therefore, this work opens new avenues for unlocking current challenges of BP nanosheet applications for practical biomedical purposes.


Subject(s)
Bacterial Infections/drug therapy , Fibroins , Nanocomposites , Phosphorus , Wound Healing/drug effects , Wound Infection/drug therapy , Animals , Cell Line , Fibroins/chemistry , Fibroins/pharmacology , Humans , Mice , Nanocomposites/chemistry , Nanocomposites/therapeutic use , Phosphorus/chemistry , Phosphorus/pharmacology
16.
ACS Appl Mater Interfaces ; 10(38): 32579-32587, 2018 Sep 26.
Article in English | MEDLINE | ID: mdl-30156821

ABSTRACT

DNA nanostructures with controllable motions and functions have been used as flexible scaffolds to precisely and spatially organize molecular reactions at the nanoscale. The construction of dynamic DNA nanostructures with site-specifically incorporated functional elements is a critical step toward building nanomachines. Artificial self-assembled DNA nanostructures have also been developed to mimic key biological processes like various small biomolecule- and protein-based functional biochemistry pathways. Here, we report a self-assembled dynamic trident-shaped DNA (TS DNA) nanoactuator, in which biomolecules can be tethered to the three "arms" of the TS DNA nanoactuator. The TS DNA nanoactuator is implemented as the mechanical scaffold for the reconfiguration of fluorescent/quenching molecules and the assembly of gold nanoparticles, which exhibit controlled spatial separation. Furthermore, two enzymes (glucose oxidase and horseradish peroxidase) are attached to the two outer arms of the TS DNA nanoactuator, which show an enhanced cascade reaction efficiency compared to free enzymes. The efficiency of the two-enzyme cascade reaction can be spatially regulated by switching the TS DNA nanoactuator between opened, semiopened, and closed states through adding the "thermodynamic drivers" (fuels or antifuels). This is the first report to precisely modulate the relative position of coupled enzyme with multiple states and only based on one dynamic DNA scaffold. The present TS DNA nanoactuator with multistage conformational transition functionality could be applied as a potential platform to precisely and dynamically control the multienzyme pathways and would broaden the scope of DNA nanostructures in single-molecule biology applications.


Subject(s)
DNA/chemistry , Nanostructures/chemistry , Gold/chemistry , Metal Nanoparticles/chemistry , Molecular Structure
17.
Talanta ; 185: 203-212, 2018 Aug 01.
Article in English | MEDLINE | ID: mdl-29759190

ABSTRACT

In the present study, procaterol hydrochloride (ProH) was successfully electropolymerized onto a glass carbon electrode (GCE) with simply cyclic voltammetry scans to construct a poly(procaterol hydrochloride) (p-ProH) membrane modified electrode. Compared with the bare GCE, much higher oxidation peak current responses and better peak potentials separation could be obtained for the simultaneous oxidation of dopamine (DA) and uric acid (UA), owning to the excellent electrocatalytic ability of the p-ProH membrane. And it's based on that a square wave voltammetry (SWV) method was developed to selective and simultaneous measurement of DA and UA. Under the optimum conditions, the linear dependence of oxidation peak current on analyte concentrations were found to be 1.0-100 µmol/L and 2-100 µmol/L, giving detection limits of 0.3 µmol/L and 0.5 µmol/L for DA and UA, separately. The as prepared modified electrode shows simplicity in construction with the merits of good reproducibility, high stability, passable selectivity and nice sensitivity. Finally, the proposed p-ProH membrane modified electrode was successfully devoted to the detection of DA and UA in biological fluids such as human serum and urine with acceptable results.


Subject(s)
Biosensing Techniques , Carbon/chemistry , Dopamine/analysis , Electrochemical Techniques , Polymers/chemistry , Procaterol/analogs & derivatives , Procaterol/chemistry , Uric Acid/analysis , Electrodes , Glass/chemistry , Humans
18.
Luminescence ; 33(4): 698-703, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29605968

ABSTRACT

In this paper, the electrochemiluminescence (ECL) behavior of luminol/H2 O2 system in the presence of bromhexine hydrochloride (BrH) was investigated. It was found that the ECL intensity of luminol/H2 O2 system on a platinum electrode could be intensely quenched by BrH owing to the scavenging superoxide radical ability of BrH, and therefore the sensitive determination of BrH was possible. Under optimal conditions, the quenched ECL intensity was linear to the concentration of BrH in a wide range of 0.08 to 500 µM, with a detection limit of 0.02 µM (signal-to-noise ratio (S/N) = 3). This ECL method possessed the merits of rapid, simple and sensitive, and was successfully applied to the BrH quantification in pharmaceutical preparations with satisfactory recoveries of 91.0 ± 4.0 to 106.5 ± 3.4%. The possible route of the quenched ECL of luminol/H2 O2 in the presence of BrH was also discussed.


Subject(s)
Bromhexine/analysis , Electrochemical Techniques , Hydrogen Peroxide/chemistry , Luminescence , Luminol/chemistry , Hydrogen-Ion Concentration , Molecular Structure
19.
Chem Commun (Camb) ; 54(25): 3142-3145, 2018 Mar 28.
Article in English | MEDLINE | ID: mdl-29527603

ABSTRACT

Gene therapy with small interfering RNA (siRNA) has been proved to be a promising technology to treat various diseases by hampering the production of target proteins. However, developing a delivery system that has high efficiency in transporting siRNA without obvious side effects remains a challenge. Herein, we designed a new survivin siRNA delivery system based on polyethyleneimine functionalized black phosphorus (BP) nanosheets which could suppress tumor growth by silencing survivin expression. Combined with the photothermal properties of the BP nanosheets, the presented delivery system shows excellent therapy efficiency for tumors. Therefore, the BP-based delivery system would be a promising tool for future clinical applications.


Subject(s)
Drug Delivery Systems , Gene Silencing/drug effects , Genetic Therapy , Nanostructures/chemistry , Phosphorus/chemistry , Phototherapy , Polyethyleneimine/chemistry , RNA, Small Interfering/pharmacology , Animals , Cell Proliferation/drug effects , Female , Humans , MCF-7 Cells , Mammary Neoplasms, Experimental/drug therapy , Mammary Neoplasms, Experimental/pathology , Mice , RNA, Small Interfering/administration & dosage
20.
Chemistry ; 24(17): 4250-4254, 2018 Mar 20.
Article in English | MEDLINE | ID: mdl-29392832

ABSTRACT

Single-layer carbon-based dots (SCDs) were chosen as a model to investigate the effect of the C-related dangling bonds with spin S=1/2 and functional groups on the electrochemiluminescent (ECL) and fluorescent (FL) properties of CDs. The C-related dangling bonds and functional groups of SCDs were tuned by chemical reduction with NaBH4 . There have several main findings via investigating the ECL and FL properties of SCDs before and after the chemical reduction. First, the FL and ECL of CDs are highly dependent on their concentration, and luminescent resonance energy transfer is observed in ECL studies when the concentration of CDs is high. Second, the ECL activity of CDs is greatly enhanced as the C-related dangling bonds increase, proving that the ECL of CDs originates from the C-related dangling bonds. Third, the FL of CDs is the synthesis of the inner FL originated from the contained isolated sp2 units and the defect FL from the C-related dangling bonds. The inner FL of CDs is enhanced greatly by removing the carboxyl groups, while the defect FL is increased slightly due to the increased C-related dangling bonds. We believe this study would promote our understanding in the ECL and FL mechanisms of CDs, advancing the applications of CDs based on their ECL and FL properties.

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