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1.
Food Chem ; 367: 130774, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34390913

RESUMO

Gas-liquid microextraction technique (GLME) has been integrated with dispersive solid phase extraction to establish a one-step sample pretreatment approach for rapid analysis of multi-class pesticides in different plant-derived foods. A 50 µL of organic solvent plus 40 mg of PSA were required throughout the 5-minute pretreatment procedure. Good trueness (recoveries of 67.2 - 105.4%) and precision (RSD ≤ 18.9%) were demonstrated by the one-step GLME method, with MLOQs ranged from 0.001 to 0.011 mg kg-1. As high as 93.6% pesticides experienced low matrix effect through this method, and the overall matrix effects (ME%) were generally better or comparable to QuEChERS. This method successfully quantified 2-phenylphenol, quintozene, bifenthrin and permethrin in the range of 0.001 - 0.008 mg kg-1 in real food samples. The multiresidue analysis feature of GLME has been validated, which displays further potential for on-site determination of organic pollutants in order to safeguard food safety and human health.


Assuntos
Resíduos de Praguicidas , Praguicidas , Humanos , Resíduos de Praguicidas/análise , Praguicidas/análise , Extração em Fase Sólida , Solventes
2.
Anal Chem ; 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34637621

RESUMO

Sensitive and precise determination of chloramphenicol (CAP) is of great significance for human health due to its high risk in trace amounts. Solid-state artificial nanochannels are expected to be highly promising sensing devices owing to single-molecule sensitivity, target-specific selectivity, and portability. Herein, we report an aptamer self-assembly-functionalized artificial nanochannel-based sensor for highly sensitive and precise determination of CAP. Aptamer self-assembly (AAs) served as the specific recognition component and were in situ grown on the surface of stable anodic aluminum oxide (AAO) nanochannels to develop an AAs@AAO nanochannel-based sensor. Selective interaction with CAP led to the disassembly of AAs and sensitive current change of AAs@AAO nanochannels, allowing sensitive and precise sensing of CAP in complex food samples. The developed AAs@AAO nanochannel-based sensor showed a wide linear range from 0.32 to 1600 pg. mL-1, low limit of detection (LOD) of 0.1 pg. mL-1, high precision with relative standard deviation of 2.9%, and quantitative recoveries of 93.4-102.2% for CAP in milk, milk powder, and honey samples. This work proposes a versatile nanochannel-based platform for facile, sensitive, and precise sensing of hazardous residues in food samples.

3.
J Hazard Mater ; 416: 125860, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492808

RESUMO

Facile synthesis of nano porous organic cages with small size and good fluorescence property is highly desirable, but still challenging and scarce for their sensing applications. Here we report a rapid room-temperature recrystallization method for the preparation of nano porous organic cages with ultra-small size as a fluorescent probe for copper ion. The prepared nano porous organic cages gave the diameter of 2.49 ± 0.04 nm, and exhibited stable emission at 535 nm with absolute quantum yield of 0.68%. On the basis of the coordination interaction and charge transfer between the nano porous organic cages and copper ion, a simple fluorescent probe for copper ion in aqueous solution was developed. The developed method gave a calibration function of QE = 0.4815lg[Cu2+] + 0.5847 (where QE is the quenching efficiency; [Cu2+] in µM) (R2 = 0.9987) in a concentration range of 0.1-2 µM, the limit of detection (3s) of 8 nM, and the relative standard deviation of 0.36% for 10 replicate determinations of 0.5 µM copper ion. The recoveries of spiked copper ion in tap water samples ranged from 96.8% to 103.0%. The proposed method possesses good sensitivity, selectivity and accuracy.


Assuntos
Cobre , Água , Fluorescência , Corantes Fluorescentes , Porosidade , Espectrometria de Fluorescência , Temperatura
4.
Anal Bioanal Chem ; 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34331090

RESUMO

The separation of amino acid (AA) enantiomers shows significance for chemistry, food, and biology, but remains challenging due to their similar properties. A promising nanoporous chiral covalent organic framework (COF) as a stationary phase for high-performance liquid chromatography (HPLC) suffers from the irregularity and widely distributed particle size of the chiral COF. Herein, we show the facile preparation of a chiral COF-monolith as a stationary phase for HPLC enantiomeric separation of AAs via orthogonal experiments. The CTzDa-monolith is prepared by the incorporation of the model chiral COF named CTzDa into the porous poly(ethylene dimethacrylate-co-methacrylate) monolith and reveals great permeability and mechanical stability. The corresponding CTzDa-monolithic column gives better chiral HPLC separation of AAs than the commercial Poroshell 120 chiral-T column. Thermal dynamic analysis and molecular docking calculations imply the involvement of stereoscopic hydrogen, π-π, and van der Waals interactions between the CTzDa and AAs during HPLC enantioseparation. The facile incorporation of the chiral COF into the porous monolith will promote the potential of a chiral COF as a stationary phase for HPLC.

5.
Talanta ; 233: 122536, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215039

RESUMO

Preparation of porphyrin-based covalent organic frameworks (Por-COFs) with high photosensitizing activity for photodynamic inactivation of bacteria is of great challenge, but significant for economy and human health. Herein, we show a conjugation-regulating strategy to design and synthesize Por-COFs with high photosensitizing activity for the photodynamic inactivation of bacteria. Terephthalaldehyde (Da), 2,5-Dihydroxyterephthalaldehyde (Dha), and 2,5-Diethoxyterephthalaldehyde (Deta) with different conjugation degrees are selected to condense with 5,10,15,20-Tetrakis(4-aminophenyl)porphyrin (Tph) to synthesize COF-366, DhaTph, and JNU-2, respectively. The higher conjugation of Dha and Deta than Da leads to the higher conjugation of DhaTph and JNU-2, respectively. Moreover, the hydroxyl group in Dha and the ethoxy group in Deta further expand the conjugation of DhaTph and JNU-2 via the formation of intralayer extended π-cloud delocalization and p-π conjunction, respectively. The extension of conjugation for DhaTph and JNU-2 results in the increase of intersystem crossing process and significantly improves their photosensitizing activity. Furthermore, JNU-2 with the highest photosensitizing activity exhibits superior antibacterial effects toward Staphylococcus aureus (99.1%) and Escherichia coli (96.8%). This study offers a new conjugation-regulating strategy for designing high photosensitizing activity of Por-COFs for the inactivation of bacteria.


Assuntos
Estruturas Metalorgânicas , Porfirinas , Antibacterianos/farmacologia , Humanos , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/farmacologia , Staphylococcus aureus
6.
Talanta ; 233: 122567, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215063

RESUMO

Photodynamic therapy (PDT) received great attention in cancer therapy due to the advantages of negligible drug resistance, low side effects, and minimal invasiveness. Development of theranostic nanoprobes with specific imaging-guided PDT is of great significance in the field. Herein we report the fabrication of a novel theranostic nanoprobe porphyrin/G-quadruplex conjugated gold/persistent luminescence nanocomposites for imaging-guided PDT. The developed nanoprobe contains NIR-emitting persistent luminescent nanoparticles (PLNP) as the core for autofluorescence-free bioimaging and Au coating on PLNP for facile subsequent DNA conjugation. The DNA sequence is designed to contain G-rich AS1411 aptamer for recognizing the over-expressed cellular nucleolin of cancer cell and forming a G-quadruplex structure to combine with tetrakis (4-carboxyphenyl) porphyrin (TCPP) to realize PDT. The AS1411 aptamer-contained DNA conjugated Au-coated PLNP is rapidly prepared via a freezing method with high content of DNA and good aqueous stability. Meanwhile, TCPP is easily loaded into the G-quadruplex structure formed from G-rich AS1411 aptamer on the surface of Au/PLNP in presence of K+. The theranostic nanoprobe gives integrated merits of PLNP for autofluorescence-free bioimging, TCPP for PDT and AS1411 aptamer-contained DNA for specific binding to cancer cells. This work provides a new specially designed imaging-guided PDT nanoplatform for theranostics.


Assuntos
Fotoquimioterapia , Porfirinas , Linhagem Celular Tumoral , Ouro , Luminescência , Medicina de Precisão
7.
ACS Appl Mater Interfaces ; 13(24): 27895-27903, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34101418

RESUMO

Phototherapy holds great promise in the treatment of bacterial infections, especially the multidrug resistant bacterial infections. However, most therapeutic agents are based on the integration of individual photothermal agents and photosensitizers, always in the activated state, and generally lack bacterial specificity, resulting in uncertain pharmacokinetics and serious nonspecific damage to normal tissues. Herein, we report a pH-responsive nanoplatform with synergistic chemo-phototherapy function for smart fluorescence imaging-guided precision sterilization. pH reversible activated symmetric cyanine was designed and prepared as a bacterial-specific imaging unit and PTT/PDT-in-one agent. Meanwhile, a guanidinium-based covalent organic framework (COF) was employed as a nanocarrier and chemotherapy agent to build the intelligent nanoplatform via electrostatic self-assembly. The self-assembly of the PTT/PDT-in-one agent and the COF greatly improves the stability and blood circulation of the PTT/PDT-in-one agent and provides charge-reversed intelligent targeting ability. The developed smart nanoplatform not only enables bacterial-targeted imaging but also possesses chemo/PTT/PDT synergetic high-efficiency bactericidal effects with little side effects, showing great potential in practical applications.


Assuntos
Antibacterianos/uso terapêutico , Corantes Fluorescentes/uso terapêutico , Estruturas Metalorgânicas/uso terapêutico , Fármacos Fotossensibilizantes/uso terapêutico , Infecções Estafilocócicas/diagnóstico por imagem , Infecções Estafilocócicas/tratamento farmacológico , Animais , Antibacterianos/química , Antibacterianos/efeitos da radiação , Escherichia coli/efeitos dos fármacos , Feminino , Corantes Fluorescentes/química , Corantes Fluorescentes/efeitos da radiação , Gadolínio/química , Gadolínio/efeitos da radiação , Indóis/química , Indóis/efeitos da radiação , Raios Infravermelhos , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/efeitos da radiação , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/efeitos da radiação , Terapia Fototérmica , Medicina de Precisão/métodos , Oxigênio Singlete/metabolismo , Staphylococcus aureus/efeitos dos fármacos
8.
Chem Asian J ; 16(15): 2022-2026, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34096181

RESUMO

A vancomycin (Van) modification strategy on a porphyrinic metal-organic framework (MOF) PCN-224 is presented. The obtained Van-PCN-224 gives the combined advantages of porphyrinic MOF and Van with high photosensitive activity and excellent targeted antibacterial activity against Staphylococcus aureus. The features make Van-PCN-224 promising for antimicrobial therapy.


Assuntos
Antibacterianos/farmacologia , Estruturas Metalorgânicas/farmacologia , Porfirinas/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Vancomicina/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Estruturas Metalorgânicas/síntese química , Estruturas Metalorgânicas/química , Testes de Sensibilidade Microbiana , Conformação Molecular , Tamanho da Partícula , Porfirinas/química , Propriedades de Superfície , Vancomicina/química
9.
Talanta ; 232: 122395, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34074391

RESUMO

Mycotoxins contamination in agricultural products poses a serious threat to human and animal health, so rapid and sensitive nanosensors for simultaneous determination of multiple mycotoxins in food samples are highly desirable for food safety monitoring. Herein, we report the fabrication of functional dual-colored persistent luminescence nanoparticles (PLNPs) in conjunction with Fe3O4 magnetic nanoparticles as a nanosensor for the simultaneous biosensing of aflatoxin B1 (AFB1) and zearalenone (ZEN) in food samples. Two types of PLNPs with a single excitation wavelength, Zn2GeO4:Mn2+ and Zn1.25Ga1.5Ge0.25O4:Cr3+,Yb3+,Er3+, are employed as the signal units, and aptamers with high affinity and specificity to the corresponding mycotoxins are used as the recognition units. The nanosensor was fabricated by hybridizing the aptamer modified PLNPs with the complementary DNA modified Fe3O4. The developed nanosensor offers the integrated merits of autofluorescence-free detection of persistent luminescence, the high specificity of aptamer and the high speed of magnetic separation, allowing highly sensitive and selective detection of AFB1 and ZEN in food samples with the limits of detection of 0.29 pg mL-1 for AFB1 and 0.22 pg mL-1 for ZEN and the recoveries of 93.6%-103.2% for AFB1 and 94.7%-105.1% for ZEN. This work also provides a novel universal PLNPs-based optical platform for the simultaneous detection of multiple contaminants in complex samples.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Micotoxinas , Zearalenona , Aflatoxina B1/análise , Animais , Contaminação de Alimentos/análise , Humanos , Limite de Detecção , Luminescência , Micotoxinas/análise , Zearalenona/análise
10.
Anal Chem ; 93(19): 7348-7354, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-33966391

RESUMO

Persistent luminescence nanoparticles (PLNPs) hold great promise for bioimaging owing to no demand for in situ excitation and negligible tissue autofluorescence interference. Nevertheless, huge challenges remain in the further development of single-emissive PLNPs due to the great variation of luminescence with time after excitation ceases. Herein, we report the controllable fabrication of dual-emissive monodispersed PLNPs (ZnGa2O4:Cr) by a surfactant-assisted hydrothermal method in combination with postcalcination for bioimaging. The prepared PLNPs emit luminescence at 508 and 714 nm with a constant luminescence ratio (I508/I714) for more than 1 h after UV excitation stops. Moreover, the prepared PLNPs give a constant I508/I714 ratio signal after repeated excitation by a LED lamp, allowing luminescence ratio imaging to ensure the long-term accuracy for in vivo imaging. In vivo ratio imaging demonstrates the potential of the prepared PLNPs for precision bioimaging. In addition, the prepared PLNPs have been applied to fabricate a theranostic nanoprobe with intelligent tumor-targeted imaging and chemo-photothermal synergistic therapy to further reveal their unique advantage for imaging guided therapy. We believe that the dual-emissive PLNPs will provide a promising nanoplatform for bioimaging and biomedical applications.


Assuntos
Nanopartículas , Neoplasias , Diagnóstico por Imagem , Humanos , Luminescência
11.
Chemistry ; 27(39): 10151-10159, 2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-33978976

RESUMO

Porphyrinic metal-organic frameworks (MOFs) are promising photosensitizers due to the lack of self-aggregation of porphyrin in aqueous solution. However, how the topology of porphyrinic MOFs affects the generation of singlet oxygen (1 O2 ) is unclear. Here, the effect of the topology of porphyrinic MOFs on their photodynamic performance is reported. Four porphyrinic zirconium MOFs (MOF-525, MOF-545, PCN-223 and PCN-224 with different topologies: ftw, csq, shp and she, respectively) were selected to study the influence of topology on the photodynamic antibacterial performance. The 1 O2 generation and the photodynamic antibacterial performance followed an decreasing order of MOF-545>MOF-525>PCN-224>PCN-223. The results reveal that the pore size, the distance between porphyrin, and the number of porphyrin per Zr6 O8 cluster in MOFs greatly affected 1 O2 generation. This work provides guidance for designing new MOFs for efficient photodynamic sterilization.


Assuntos
Estruturas Metalorgânicas , Porfirinas , Fármacos Fotossensibilizantes , Esterilização , Zircônio
12.
Talanta ; 225: 122046, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33592768

RESUMO

Near-infrared (NIR) aggregation-induced emission (AIE) of previous organic photosensitizers is usually weak because of the competition between twisted intramolecular charge transfer (TICT) effect and AIE. Herein, we report a rational molecular design strategy to boost NIR AIE of photosensitizers and still to keep strong 1O2 production capacity via rotor effect. To this end, one new triphenylamine (TPA)-based AIE photosensitizer, TPAM-1, is designed to give strong ability to generate 1O2 but weak NIR fluorescence in the aggregate state due to the strong TICT effect. Another new TPA-based AIE photosensitizer, TPAM-2, is designed by introducing three p-methoxyphenyl units as rotors into the structure of TPAM-1 to modulate the competition between AIE and TICT. TPAM-1 and TPAM-2 exhibit stronger ability to generate 1O2 in the aggregate state than the commercial photosensitizer, Ce6. Furthermore, TPAM-2 gives much brighter NIR luminescence (25-times higher quantum yield) than TPAM-1 in the aggregate state due to the rotor effect. TPAM-2 with strong NIR AIE and 1O2 production capability was encapsulated by DSPE-PEG2000 to give good biocompatibility. The DSPE-PEG2000-encapsulated TPAM-2 nanoparticles show good cell imaging performance and remarkable photosensitive activity for killing HeLa cells. This work provides a new way for designing ideal photosensitizers for AIE imaging-guided photodynamic therapy.


Assuntos
Neoplasias , Fotoquimioterapia , Diagnóstico por Imagem , Fluorescência , Células HeLa , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/farmacologia
13.
Anal Chem ; 93(4): 2589-2595, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33410662

RESUMO

Selective and sensitive determination of trace kanamycin in complex food samples is of great importance for food safety because of its high toxicity. Here, we report a sensitive and autofluorescence-free persistent luminescence (PL) aptasensor for selective, sensitive, and autofluorescence-free determination of kanamycin in food samples. The aptamer for kanamycin was first conjugated onto the surface of magnetic nanoparticles Fe3O4 to serve as the recognition unit as well as the separation element, while the PL nanoparticles ZnGa2O4:Cr (PLNPs) were functionalized with the aptamer complementary DNA (cDNA) as the PL signal. The PL aptasensor consisted of the aptamer-conjugated MNPs (MNPs-apt) and cDNA-functionalized PLNPs (PLNPs-cDNA) and combined the merits of the long-lasting luminescence of PLNPs, the magnetic separation ability of MNPs as well as the selectivity of the aptamer, offering a promising approach for autofluorescence-free determination of kanamycin in food samples. The proposed aptasensor showed excellent linearity in the range from 1 pg mL-1 to 5 ng mL-1 with a limit of detection of 0.32 pg mL-1. The precision for 11 replicate determinations of 100 pg mL-1 kanamycin was 3.1% (relative standard deviation). The developed aptasensor was applied for the determination of kanamycin in milk and honey samples with the recoveries of 95.4-106.3%. The proposed aptasensor is easily extendable to other analytes by simply replacing the aptamer, showing great potential as a universal aptasensor platform for selective, sensitive, and autofluorescence-free detection of hazardous analytes in food samples.


Assuntos
Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Canamicina/química , Medições Luminescentes/métodos , Animais , Técnicas Biossensoriais , Compostos Ferrosos , Mel/análise , Nanopartículas Metálicas , Leite/química , Pós/química
14.
Angew Chem Int Ed Engl ; 60(5): 2398-2405, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33073905

RESUMO

Persistent luminescent nanoparticles (PLNPs) with intrinsic stimuli-responsive properties are desirable because of no autofluorescence background and natural responsive luminescence. However, the stimuli-responsive features of pure PLNPs have been unexplored. Here we show a facile one-pot hydrothermal synthesis of green-emitting Zn2 GeO4 :Mn2+ ,Pr3+ nanoparticles (ZGMP) with regular shape, uniform size and good afterglow luminescent performance. We also report the pH stimuli-responsive luminescent behavior of ZGMP and its possible mechanism. Taking the intriguing feature of pH responsive persistent luminescence, we explore ZGMP as autofluorescence-free probes to achieve stimuli-activated signal switch for biosensing by integrating enzyme catalysis reaction mediated pH modulation. The pH-responsive persistent luminescence also makes ZGMP promising for high-level information encryption.


Assuntos
Nanopartículas/química , Técnicas Biossensoriais , Humanos , Luminescência
15.
Talanta ; 219: 121209, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32887113

RESUMO

Theranostic nano-drug delivery systems are promising candidates for early diagnosis and treatment of tumors. However, it is a great challenge to achieve accurate intracellular delivery and stimuli-responsive drug release with the enhanced anti-tumor effects and reduced side effects. Herein we report the fabrication of polyamide-amine (PAMAM) dendrimer grafted persistent luminescence nanoparticles (PLNPs) via in situ growth of PAMAM on the surface of PLNPs and its application in targeted bioimaging and drug delivery. The developed PLNPs-PAMAM possesses strong renewable near-infrared persistent luminescence for imaging and gives abundant terminal groups for further functionalization. Aptamer AS1411 coupled to the PLNPs-PAMAM surface can specifically bind to the over-expressed nucleolin on the membrane of tumor cells and improve the intracellular accumulation of the nanoparticles. Doxorubicin (DOX) is loaded on PLNPs-PAMAM by a pH-sensitive hydrazine, can be specifically released in the intracellular acid environment, leading to apoptosis of HeLa tumor cells and inhibition of tumor growth. The as-prepared smart drug delivery nanoplatform with persistent luminescence, PLNPs-PAMAM-AS1411/DOX, shows a good application prospect for precise cancer theranostics.


Assuntos
Dendrímeros , Nanopartículas , Neoplasias , Preparações Farmacêuticas , Doxorrubicina/uso terapêutico , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Humanos , Luminescência , Neoplasias/tratamento farmacológico
16.
ACS Appl Mater Interfaces ; 12(41): 45850-45858, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32975404

RESUMO

Photodynamic sterilization is the most promising method to combat bacterial infection, especially multidrug-resistant bacterial infection. However, the absorption of conventional photosensitizers is mostly located in the UV-vis region, leading to limited penetration depth and poor therapeutic efficacy for deep-tissue bacterial infection. Besides, most of the photosensitizers are always in the activated state and lack bacteria-targeting ability, which inevitably causes severe nonspecific damage to normal tissues. Here, we show the design of a pH reversibly switchable near-infrared photosensitizer-based nanocapsule for precision bacteria-targeting fluorescence imaging-guided photodynamic sterilization. pH reversibly activatable asymmetric cyanine was synthesized as a bacteria-specific imaging unit and smart photosensitizer to realize precision imaging-guided targeting sterilization without side effects. An allicin mimic was introduced into the smart photosensitizer as the auxiliary bactericidal group to further enhance antibacterial efficiency. Meanwhile, amphipathic functionalized polyethylene glycol was employed to fabricate the nanocapsule by self-assembly to endow the charge-reversed intelligent targeting ability and prolong blood circulation. The developed switchable nanocapsule not only enables precision bacterial infection-targeted imaging without background fluorescence interference but also gives an efficient bactericidal effect with excellent specificity and negligible side effects, holding great potential for practical application.


Assuntos
Antibacterianos/farmacologia , Nanocápsulas/química , Imagem Óptica , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Animais , Antibacterianos/química , Sobrevivência Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Raios Infravermelhos , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Células NIH 3T3 , Fármacos Fotossensibilizantes/química , Staphylococcus aureus/efeitos dos fármacos
17.
Talanta ; 218: 121101, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32797868

RESUMO

Serious ochratoxin A (OTA) contamination necessitates the development of rapid, sensitive and selective analytical methods for its determination in food safety. Herein, we report a persistent luminescence resonance energy transfer (LRET) based aptasensor for the autofluorescence-free detection of OTA. OTA aptamer functionalized persistent luminescence nanorod (PLNR) Zn2GeO4:Mn2+ and the aptamer complementary DNA modified gold nanoparticle (AuNP) were used as the donor and the acceptor, respectively. The developed LRET aptasensor integrated the advantages of the long-lasting persistent luminescence of PLNR, the high selectivity of aptamer and the low probe background of LRET sensors, allowing autofluorescence-free detection of OTA in biological samples with high sensitivity and selectivity. The developed LRET aptasensor gave an excellent linearity in the range of 0.01-10 ng mL-1, the detection limit of 3 pg mL-1 and the precision of 2.7% (RSD, n = 11) at 1 ng mL-1 level. The applicability of the developed aptasensor was demonstrated by analyzing beer samples for OTA with the recoveries of 92.3%-104%.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanopartículas Metálicas , Micotoxinas , Nanotubos , Ocratoxinas , Ouro , Limite de Detecção , Luminescência , Ocratoxinas/análise
18.
J Mater Chem B ; 8(35): 8071-8083, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32785386

RESUMO

Efficient drug nanocarriers with high drug loading capacity and luminescent ability are in high demand for biomedical applications. Here we show a facile and bio-friendly synthesis of macrophage membrane coated persistent luminescence nanoparticle (PLNP)@metal-organic framework (MOF)-derived mesoporous carbon (MC) core-shell nanocomposites (PLMCs) for autofluorescence-free imaging-guided chemotherapy. MOF UiO-66 is used as both the precursor and the template, and is controllably coated on the surface of the PLNP to form a PLNP@UiO-66 core-shell composite. Subsequent calcination enables the transformation of PLNP@UiO-66 to PLMC due to the pyrolysis of the UiO-66 shell. PLMC with a small particle size of 70 nm, a tunable large pore size from ∼4.8 to ∼16.2 nm in the shell and near-infrared persistent luminescence in the core was prepared by controlling the calcination conditions. The prepared PLMC showed an enhanced drug loading capacity for three model drugs (doxycycline hydrochloride, acetylsalicylic acid, and paclitaxel) compared with PLNP@UiO-66. Further coating of the macrophage membrane on the surface of PLMC results in MPLMC with enhanced cloaking ability for evading the mononuclear phagocyte system. The drug-loaded MPLMC is promising for autofluorescence-free persistent luminescence imaging-guided drug delivery and tumor therapy.


Assuntos
Carbono/química , Membrana Celular/metabolismo , Macrófagos/citologia , Estruturas Metalorgânicas/química , Nanocompostos/química , Nanopartículas/química , Imagem Óptica , Linhagem Celular Tumoral , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Humanos , Tamanho da Partícula , Porosidade
19.
Angew Chem Int Ed Engl ; 59(40): 17607-17613, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32497359

RESUMO

Design of stable adsorbents for selective gold recovery with large capacity and fast adsorption kinetics is of great challenge, but significant for the economy and the environment. Herein, we show the design and preparation of an irreversible amide-linked covalent organic framework (COF) JNU-1 via a building block exchange strategy for efficient recovery of gold. JNU-1 was synthesized through the exchange of 4,4'-biphenyldicarboxaldehyde (BA) in mother COF TzBA consisting of 4,4',4''-(1,3,5-triazine-2,4,6-triyl)trianiline (Tz) and BA with terephthaloyl chloride. The irreversible amide linked JNU-1 gave good stability, unprecedented fast kinetics, excellent selectivity and outstanding adsorption capacity for gold recovery. X-ray photoelectron spectroscopy along with thermodynamic study and quantum mechanics calculation reveals that the excellent performance of JNU-1 for gold recovery results from the formation of hydrogen bonds C(N)-H⋅⋅⋅Cl and coordinate interaction of O and Au. The rational design of irreversible bonds as both inherent linkage and functional groups in COFs is a promising way to prepare stable COFs for diverse applications.

20.
Chempluschem ; 85(5): 828-831, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32364333

RESUMO

Development of efficient adsorbents for nitrate removal is vital for tackling increasing nitrate contamination. We report a free-radical polymerization strategy to prepare a cationic surfactant-modified covalent organic framework (DhaTab-S) for removing nitrate ions from aqueous solution. DhaTab-S was prepared by grafting a cationic surfactant diallyldimethylammonium chloride solution on vinyl-containing COF (DhaTab-V). The adsorption capacity for nitrate was pH-dependent with the maximum at pH 6, and the adsorption process was largely influenced by ionic strength. The adsorption equilibrium for nitrate on DhaTab-S was reached within 40 minutes and followed pseudo-second-order kinetics. DhaTab-S showed a nitrate adsorption capacity of 108.8 mg g-1 , which is about 15 times that of COF before surfactant modification. The large adsorption capacity makes DhaTab-S a promising candidate for nitrate removal from aqueous media.

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