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1.
J Alzheimers Dis ; 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-32007956

RESUMO

The blood-brain barrier (BBB) can restrict the therapeutic effects of Alzheimer's disease (AD) medications. While a large number of AD drug treatment trials targeting BBB dynamics have emerged, most have failed due to insufficient permeability. Furthermore, a subset of AD cases, which also feature chronic hypoperfusion are complicated by BBB deficits. We used a mouse model of AD with chronic hypoperfusion-transgenic mice (PS1V97L) with right common carotid artery ligation. In this model, we assessed how chronic cerebral hypoperfusion changed the pathophysiological processes that increase BBB permeability. Compared with control mice, AD mice with chronic hypoperfusion revealed significantly upregulated expression of the receptor for advanced glycation end products (RAGE) on the BBB. Upregulated RAGE caused increased accumulation of amyloid-ß (Aß) in the brain in these mice. Upregulation of RAGE (or binding to Aß) can promote activation of the NF-κB pathway and enhance oxidative stress and increase the release of pro-inflammatory factors. These factors promoted the reduction of tight junction proteins between the endothelial cells in the BBB and increased its permeability. These findings suggest that the transporter RAGE dysregulation on the BBB initiates a series of pathophysiological processes which lead to increased BBB permeability. Taken together, we have shown that chronic hypoperfusion can serve to enhance and aggravate the BBB impairment in AD.

2.
Cell Res ; 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32051560

RESUMO

N6-methyladenine (N6-mA) of DNA is an emerging epigenetic mark in mammalian genome. Levels of N6-mA undergo drastic fluctuation during early embryogenesis, indicative of active regulation. Here we show that the 2-oxoglutarate-dependent oxygenase ALKBH1 functions as a nuclear eraser of N6-mA in unpairing regions (e.g., SIDD, Stress-Induced DNA Double Helix Destabilization regions) of mammalian genomes. Enzymatic profiling studies revealed that ALKBH1 prefers bubbled or bulged DNAs as substrate, instead of single-stranded (ss-) or double-stranded (ds-) DNAs. Structural studies of ALKBH1 revealed an unexpected "stretch-out" conformation of its "Flip1" motif, a conserved element that usually bends over catalytic center to facilitate substrate base flipping in other DNA demethylases. Thus, lack of a bending "Flip1" explains the observed preference of ALKBH1 for unpairing substrates, in which the flipped N6-mA is primed for catalysis. Co-crystal structural studies of ALKBH1 bound to a 21-mer bulged DNA explained the need of both flanking duplexes and a flipped base for recognition and catalysis. Key elements (e.g., an ALKBH1-specific α1 helix) as well as residues contributing to structural integrity and catalytic activity were validated by structure-based mutagenesis studies. Furthermore, ssDNA-seq and DIP-seq analyses revealed significant co-occurrence of base unpairing regions with N6-mA in mouse genome. Collectively, our biochemical, structural and genomic studies suggest that ALKBH1 is an important DNA demethylase that regulates genome N6-mA turnover of unpairing regions associated with dynamic chromosome regulation.

3.
Chem Commun (Camb) ; 56(12): 1879-1882, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-31951226

RESUMO

Two organic hole-transporting materials comprising a two-dimensional triphenylene core and methoxyl-arylamine terminal units are developed and applied in perovskite solar cells. Enhanced photovoltaic and stability performance are obtained using TPH-T compared with those of spiro-OMeTAD.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 230: 118061, 2020 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-31958606

RESUMO

Thiophenol has a broad application in agriculture and industry. However, thiophenol can harm to the environment and health for its high toxicity. Developing an effective method for detection of thiophenol in the field of environmental and biology is valuable. In this work, we construct a reaction-based ratiometric fluorescent probe (E)-4-(2-(7-(diethylamino)-2-oxo-2H-chromen-3-yl)vinyl)-1-(4-(2,4-dinitrophenoxy)benzyl)pyridin-1-ium bromide (DCVP-DNP) for probing thiophenol in environment and cells by employing (E)-7-(diethylamino)-3-(2-(pyridin-4-yl)vinyl)-2H-chromen-2-one (DCVP) as the fluorophore and 2,4-dinitrophenyl (DNP) ether as the recognition group for the first time. The probe has high selectivity for thiophenol though thiophenol-triggered nucleophilic substitution reaction. In addition, the ratio of emission intensities of the probe has linearly with thiophenol concentration in the range of 0-65 µM and the detection limit of thiophenol is as low as 4.8 × 10-8 M. Moreover, the probe can not only be applied for detection of thiophenol in water samples, but also image thiophenol in living cells, suggesting its potential application in environment and biological system.

5.
Anal Chim Acta ; 1098: 133-139, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31948576

RESUMO

Telomerase activity is inhibited in normal somatic cells but abnormally high in the majority of cancer cells. Maintenance of active telomerase in cancer cells promotes proliferation and immortalization. With the difference in telomerase activity between cancer and normal cells in mind, we designed a nanoprobe based on quantum dot (QD) and fluorescence resonance energy transfer (FRET). The nanoprobe consisted of a specific sequence of DNA with the two ends labeled with QD as a fluorescent donor and Alexa488 as a fluorescent acceptor, respectively. FRET signal tracking was performed by adjusting the distance between donors and acceptors, and changes in the FRET signal shown to be related to telomerase activity. Incubation of cells with the nanoprobe facilitated sensing of intracellular telomerase activity, and consequent discrimination between normal and cancer cells. Our novel DNA nanoprobe based on QD-FRET achieved sensitive detection of telomerase in cells up to a detection limit of one cell, and quantitative detection of telomerase activity in different numbers of cells. The nanoprobe generated in this study is expected to allow dynamically monitoring of the changes in telomerase activity in cells under treatment with drugs, providing a potential basis for early diagnosis and management of cancer.

7.
Talanta ; 210: 120612, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31987202

RESUMO

A new strategy endowing probe with large Stokes shift, high quantum yield and red emission was developed by incorporating tetrahydroquinoxaline unit and five-membered pyrrolidine ring on fluorophore. As demonstrated, a novel probe was rationally designed and synthesized for sensitive monitor of cellular cysteine (Cys) and endogenous aminoacylase with large Stokes shift and high quantum yield.

8.
J Cancer Res Clin Oncol ; 146(2): 485-492, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31686248

RESUMO

PURPOSE: Early death (ED) is the main cause of acute promyelocytic leukemia (APL) treatment failure, and the ED rate is higher for elderly patients than that for young ones. To date, no studies have been found focusing on ED in elderly patients with APL. METHODS: This study retrospectively analyzed the clinical data of 409 consecutive patients with APL (139 patients ≥ 50 years old, 270 patients < 50 years old). All patients received arsenic trioxide alone as induction therapy. The baseline clinical characteristics and ED occurrence and predictors between elderly and young patients with APL were compared and analyzed. RESULTS: The clinical features of elderly patients at admission were not significantly different from those of young ones. The ED rate of elderly patients was significantly greater than that of young patients (23.74% vs 11.85%, P = 0.0018). Hemorrhage is the main cause of ED in elderly patients, followed by infection and differentiation syndrome. From the 15th to 30th days of treatment, elderly patients had a higher mortality rate than that of young patients (7.83% vs 2.06%, P = 0.009). Male, white blood cell (WBC) count > 10 × 109/L, fibrinogen < 1.0 g/L and low albumin levels were independent risk factors for ED in elderly patients, while ED was only correlated with WBC count, fibrinogen and creatinine levels in young patients. CONCLUSION: The results of this study may help design more rational treatment plans for elderly patients with APL based on early mortality risk to reduce the ED rate.

9.
J Cell Biochem ; 121(1): 25-42, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31433522

RESUMO

Myocardial dysfunction is an important manifestation of sepsis. In addition, inactivation of the mitogen-activated protein kinase (MAPK) signaling pathway has been reported to be beneficial in sepsis. The current study used gene expression profiling to demonstrate the overexpression of angiotensin II type 1 receptor (AT1R) and activation of the MAPK signaling pathway in sepsis. In this study, we used a rat model of sepsis established by cecal ligation and puncture to explore the mechanism of AT1R silencing in relation to the MAPK signaling pathway on myocardial injury. Various parameters including blood pressure, heart rate, and cardiac function changes were observed. Enzyme-linked immunosorbent assay was used to measure the concentration of cardiac troponin T (TnT), cardiac troponin I (cTnI), and creatine kinase isoenzyme muscle/brain (CK-MB). Myocardial enzyme, tissue antioxidant capacity, mitochondria swelling, and membrane potential were also detected. Terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling staining was applied to measure cell apoptosis, and messenger RNA and protein levels of apoptosis-related proteins (Fas ligand [Fasl], B-cell CLL/lymphoma [Bcl-2], p53) were also detected. Initially, sepsis rats exhibited decreased survival rate, but increased ejection fraction (EF), heart rate, and concentrations of TnT, cTnI, and CK-MB. Furthermore, decreased AT1R expression inactivated the MAPK signaling pathway (shown as decreased extracellular signal-regulated kinase and cyclic adenosine 3',5'-monophosphate response element binding protein expression), decreased EF, heart rate, and concentrations of TnT, cTnI, and CK-MB, but increased sepsis rat survival rate. Eventually, decreased AT1R expression inhibited myocardial cell apoptosis (shown as decreased apoptosis rate and p53 and Fasl expression as well as increased Bcl-2 expression). These findings indicated that AT1R silencing plays an inhibitory role in sepsis-induced myocardial injury by inhibiting the MAPK signaling pathway.

10.
Nature ; 577(7788): 121-126, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31853060

RESUMO

Modifications of histone proteins have essential roles in normal development and human disease. Recognition of modified histones by 'reader' proteins is a key mechanism that mediates the function of histone modifications, but how the dysregulation of these readers might contribute to disease remains poorly understood. We previously identified the ENL protein as a reader of histone acetylation via its YEATS domain, linking it to the expression of cancer-driving genes in acute leukaemia1. Recurrent hotspot mutations have been found in the ENL YEATS domain in Wilms tumour2,3, the most common type of paediatric kidney cancer. Here we show, using human and mouse cells, that these mutations impair cell-fate regulation by conferring gain-of-function in chromatin recruitment and transcriptional control. ENL mutants induce gene-expression changes that favour a premalignant cell fate, and, in an assay for nephrogenesis using murine cells, result in undifferentiated structures resembling those observed in human Wilms tumour. Mechanistically, although bound to largely similar genomic loci as the wild-type protein, ENL mutants exhibit increased occupancy at a subset of targets, leading to a marked increase in the recruitment and activity of transcription elongation machinery that enforces active transcription from target loci. Furthermore, ectopically expressed ENL mutants exhibit greater self-association and form discrete and dynamic nuclear puncta that are characteristic of biomolecular hubs consisting of local high concentrations of regulatory factors. Such mutation-driven ENL self-association is functionally linked to enhanced chromatin occupancy and gene activation. Collectively, our findings show that hotspot mutations in a chromatin-reader domain drive self-reinforced recruitment, derailing normal cell-fate control during development and leading to an oncogenic outcome.

11.
Orthop Surg ; 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31840344

RESUMO

OBJECTIVE: To investigate whether use of single-foot centered and double-foot centered weight-bearing X-rays has an impact on the relevant indicators of hallux valgus. METHODS: A total of 55 female patients from the Department of Ankle Surgery of Beijing Tongren Hospital with hallux valgus (110 feet) were collected from September to December 2015. The age of these patients ranged from 18 to 43 years, with an average age of 47.9 ± 8.5 years. All selected patients fit the diagnostic criteria of hallux valgus and had weight-bearing single foot centered and double foot centered radiographs taken. During the projection, all patients were instructed to stand on the X-ray box, with the knee joint straightened and legs perpendicular to the floor. The projection center of the single foot was directed at the lateral part of the scaphoid bone of the foot, while the projection center was directed at the position between the scaphoid bones of both feet for the double-foot shooting. The hallux valgus angle (HAV), the intermetatarsal angle between the first and second metatarsals (IMA), the intermetatarsal angle between the first and fifth metatarsals (IM1-5), and the metatarsal adduction angle (MAA) were measured and examined. The difference between these two shooting conditions was compared and analyzed. RESULTS: The differences in X-ray measurement results (IMA, HAV, IM1-5, and MMA) between different measures for the same patient were not statistically significant. The values of HAV, IMA, IM1-5, and MAA are common indexes for evaluating hallux valgus. The average IMA was 15.9° for single-foot centered and 14.1° for double-foot centered X-rays. The average HAV was 30.2° for single-foot centered and 29.7° for double-foot centered X-rays. The average IM1-5 was 31.1° for single-foot centered and 29.7° for double-foot centered X-rays. The average of metatarsal adduction angle was 13.8° for single-foot centered and 14.1° for double-foot centered X-rays. The differences between single-foot centered and double-foot centered X-rays were statistically significant in terms of the measurement index (P < 0.05). In addition, compared with double-foot centered weight-bearing X-rays, the focus of single-foot centered X-rays was located on the lateral part of the scaphoid bone of the foot, and the ray was closer to the vertical foot in the single-foot centered weight-bearing X-ray. CONCLUSION: When the weight-bearing position and projection distance are the same, the single-foot centered weight-bearing X-ray is more effective in evaluating the severity of hallux valgus compared with the double-foot centered weight-bearing X-ray.

12.
Int J Mol Sci ; 20(23)2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31775305

RESUMO

The pathological features of Alzheimer's Disease (AD) first appear in the medial temporal lobe and then in other brain structures with the development of the disease. In this work, we investigated the association between genetic loci and subcortical structure volumes of AD on 393 samples in the Alzheimer's Disease Neuroimaging Initiative (ADNI) cohort. Brain subcortical structures were clustered into modules using Pearson's correlation coefficient of volumes across all samples. Module volumes were used as quantitative traits to identify not only the main effect loci but also the interactive effect loci for each module. Thirty-five subcortical structures were clustered into five modules, each corresponding to a particular brain structure/area, including the limbic system (module I), the corpus callosum (module II), thalamus-cerebellum-brainstem-pallidum (module III), the basal ganglia neostriatum (module IV), and the ventricular system (module V). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment results indicate that the gene annotations of the five modules were distinct, with few overlaps between different modules. We identified several main effect loci and interactive effect loci for each module. All these loci are related to the function of module structures and basic biological processes such as material transport and signal transduction.

13.
Chem Commun (Camb) ; 55(98): 14848-14851, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31769449

RESUMO

HDAC6 (histone deacetylase 6) catalyses the deacetylation of non-histone substrates, and plays important roles in cell migration, protein degradation and other cellular processes. Here we report that CRBN-recruiting PROTAC NH2, which introduces pomalidomide at the benzene ring of Nex A, reaches comparable degradation efficiency of HDAC6 compared to aliphatic-chain-introducing PROTAC NP8.

14.
Mikrochim Acta ; 186(12): 754, 2019 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-31705210

RESUMO

The authors describe a dual-signal colorimetric and ratiometric fluorescent probe for uric acid (UA). It is based on cascade catalysis and an inner filter effect. The method involves uricase-catalyzed oxidation of UA and iodide-catalyzed oxidation of the colorless peroxidase substrate o-phenylenediamine (OPD) to form yellow 2,3-diaminophenazine (oxOPD). This can be visually observed or monitored by measuring absorbance at 417 nm. Furthermore, oxOPD quenches the fluorescence of silicon nanoparticles (SiNPs) (with peaks at 450 and 565 nm) via an inner filter effect. The change in the ratio of emissions peaking 565 and 450 (at excitation wavelength of 380 nm) increases linearly in the 0.01-0.8 mM UA concentration range). The lower detection limits are 8.4 and 0.75 µM when using the colorimetric and ratiometric fluorometric method, respectively. The assay was successfully applied to the quantitation of UA in spiked serum samples. Graphical abstractA dual-signal colorimetric and ratiometric fluor ometric assay was developed for uric acid (UA). The fluorometric assay is based on the inner filter effect between fluorescent silicon nanoparticles and 2,3-diaminophenazine. It involves uricase-catalyzed oxidation of UA, and iodide-catalyzed oxidation of o-phenylenediamine.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31708458

RESUMO

Peroxynitrite (ONOO-) is a primary kind of reactive oxygen species. Excessive ONOO- can induce oxidative damage to biomolecules and further results in various diseases. So, quantitative monitoring ONOO- with excellent selectivity and sensitivity is imperative for elucidating its role in biological processes. In this study, a novel pyridinium fluorescent ONOO- probe (CPC) has been constructed base on ICT-modulated by combining coumarin fluorophore and diphenylphosphinate recognition group. The fluorescence response of CPC for ONOO- is realized via the removal of diphenylphosphinate group. The probe CPC shows prominent features for detection of ONOO- including fast response rate (within 3 min), excellent selectivity and sensitivity, distinct colorimetric (red to green), and a large emission wavelength shift (105 nm). The emission intensity ration (I538/I643) exhibits 153-fold enhancement along with the increasing ONOO- and the detection limit is as low as 1.60 × 10-8 M. These good response properties make CPC possible to quantitative detection of ONOO- concentration. By using the strategy, the ratiometric CPC has been employed to detection of mitochondrial ONOO- in live cell successfully.

16.
Int Immunopharmacol ; 77: 105939, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31718930

RESUMO

BACKGROUND: Ambient fine particulate matter (PM2.5) could induce lung injury. Aryl hydrocarbon receptor (AhR) is involved in the molecular mechanisms of prooxidative and pro-inflammatory effect of PM2.5. Molecular hydrogen has antioxidant properties. The protective effect and mechanism of hydrogen on PM2.5-induced lung injury remain unclear. OBJECTIVES: This study aimed to determine whether hydrogen could alleviate lung injury in a rat model of subacute exposure to concentrated ambient PM2.5, and explore the mechanism related to AhR. METHODS: Male Wastar rats were exposed to either concentrated ambient particles (CAPs) (diameter: ≤2.5 µm, average concentration: 1328 ±â€¯730 µg/m3) or filtered air (FA) by nose-only inhalation (5 h/day, 5 days/week for 4 weeks). Hydrogen-treated rats inhaled 66.7% hydrogen from water electrolysis for 2 h after each exposure to CAPs or FA. RESULTS: CAPs inhalation induced lung injury, as demonstrated by pulmonary function decrease, histopathological damage, mucus hypersecretion [Periodic acid-Schiff (PAS) staining for mucins, immunohistochemistry and quantitative real-time PCR (RT-qPCR) for mucin 5AC (MUC5AC) expression], increased pro-inflammatory cytokines (TNF-α, IL-8 and IL-1ß) and oxidative damage indexes [malondialdehyde (MDA) and 8-isoprostane F2α (8-iso-PG)]. While, hydrogen inhalation significantly alleviated the damages mentioned above. In addition, low expression of AhR in lung tissues determined by Western Blot was found after CAPs exposure, whereas hydrogen inhibited AhR decline induced by CAPs. CONCLUSIONS: High concentrations of hydrogen could ameliorate pulmonary dysfunction, airway mucus hypersecretion, oxidation damage, and inflammation response in rats exposed to concentrated ambient PM2.5. Additionally, hydrogen alleviates lung injury induced by PM2.5 possibly through AhR-dependent mechanisms.

17.
Cell Discov ; 5: 35, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31636949

RESUMO

Chemical modifications on histones constitute a key mechanism for gene regulation in chromatin context. Recently, histone lysine ß-hydroxybutyrylation (Kbhb) was identified as a new form of histone acylation that connects starvation-responsive metabolism to epigenetic regulation. Sirtuins are a family of NAD+-dependent deacetylases. Through systematic profiling studies, we show that human SIRT3 displays class-selective histone de-ß-hydroxybutyrylase activities with preference for H3 K4, K9, K18, K23, K27, and H4K16, but not for H4 K5, K8, K12, which distinguishes it from the Zn-dependent HDACs. Structural studies revealed a hydrogen bond-lined hydrophobic pocket favored for the S-form Kbhb recognition and catalysis. ß-backbone but not side chain-mediated interactions around Kbhb dominate sequence motif recognition, explaining the broad site-specificity of SIRT3. The observed class-selectivity of SIRT3 is due to an entropically unfavorable barrier associated with the glycine-flanking motif that the histone Kbhb resides in. Collectively, we reveal the molecular basis for class-selective histone de-ß-hydroxybutyrylation by SIRT3, shedding lights on the function of sirtuins in Kbhb biology through hierarchical deacylation.

18.
BMJ Open ; 9(10): e031098, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31630106

RESUMO

BACKGROUND: In China, the local health insurance coverage is usually related to timely reimbursement of hypertensive care in primary care settings, while health insurance that is not local could represent an obstacle for accessibility and affordability of primary care for hypertensive patients. OBJECTIVE: To investigate whether local health insurance schemes have a positive impact on hypertension management and control. DESIGN: We performed an on-site, face-to-face, patients survey in community health centres (CHCs) in Shenzhen, China. SETTING AND PARTICIPANTS: Hypertensive patients seeking healthcare from CHCs were selected as study participants using a systematic sampling design. MAIN MEASURES: We obtained information about insurance status, social capital, drug treatment and control of hypertension. Multivariable stepwise logistic regression models were constructed to test the associations between insurance status and hypertension management, as well as insurance status and social capital. RESULTS: A total of 867 participants were included in the final study analysis. We found that the participants covered by local insurance schemes were more likely to be managed in primary care facilities (61.1% vs 81.9%; OR=2.58, 95% CI: 1.56 to 4.28), taking antihypertensive drugs (77.2% vs 88.0%; OR=2.23, 95% CI: 1.37 to 3.62) and controlling blood pressure (43.0% vs 52.4%; OR=1.46, 95% CI: 1.03 to 2.07) when compared with those with insurance coverage that is not local. The participants covered by local insurance schemes reported a higher score of perceived generalised trust than those without (4.23 vs 3.97; OR=0.74, 95% CI: 0.53 to 0.86). CONCLUSION: Our study demonstrates that local health insurance coverage could help improve management and control of hypertension in a primary care setting. Policymakers suggest initiating social interventions for better management and control of hypertension at the primary care level, although the causal pathways across insurance status, social capital and control of hypertension deserve further investigations.

19.
Analyst ; 144(23): 6962-6967, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31621707

RESUMO

The monitoring of heavy transition metals has increasingly attracted great attention because they pollute the environment and have unique physiological functions. Chemosensors are useful tools for monitoring heavy transition metals due to their simple visualization, excellent sensitivity and high selectivity. Herein, we have developed a novel chemosensor for the detection of water-soluble Cu2+ and Ni2+ species with different mechanisms, and low detection limits of 2.1 nM for Cu2+ and 1.2 nM for Ni2+ were obtained. The colorimetric probe CPH has been applied to qualitative and quantitative detection of Cu2+ and Ni2+ species in real samples.

20.
ACS Appl Mater Interfaces ; 11(44): 41602-41610, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31609573

RESUMO

It is a challenge to produce single-crystalline gold nanoparticles having regular size definition designed for controlled light absorbance and internal structural inhomogeneities to enhance electro-magnetic fields. Here, we report a synthetic strategy to generate large single-crystalline triangular or hexagonal gold nanoplates with multiple cracks within the plates using a graphene-polyelectrolyte complex as both a surface adsorbent and bulk reducing agent. Large-scale gold nanoplates can be synthesized within 48 h. First-principles calculations indicate that the nanoplates have a kinetically limited morphology resulting from prior growth of {111} facets confined by the graphene-polyelectrolyte multilayer. The nanocracks result from the inability of the bulk reducing agent to enter narrow defect spaces during growth that remained permanently. The nanoplates had extraordinary physical-chemical detection sensitivity when used for surface-enhanced Raman scattering (SERS) and surface-enhanced infrared absorption (SEIRA). The limit of rhodamine 6G (Rh6G) SERS detection is as low as 5 × 10-13 M. The gold nanoplates also showed a remarkable light-to-heat conversion efficiency (68.5%). The approach described may be applicable to other metals so that tunable nanostructures can be generated by the graphene-polyelectrolyte multilayer strategy.

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