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1.
Chem Sci ; 15(24): 9298-9317, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38903228

RESUMO

An innovative design strategy of placing sulfur (S)-atoms within the pendant functional groups and at carbonyl positions in conventional perylenimide (PNI-O) has been demonstrated to investigate the condensed state structure-property relationship and potential photodynamic therapy (PDT) application. Incorporation of simply S-atoms at the peri-functionalized perylenimide (RPNI-O) leads to an aggregation-induced enhanced emission luminogen (AIEEgen), 2-hexyl-8-(thianthren-1-yl)-1H-benzo[5,10]anthra[2,1,9-def]isoquinoline-1,3(2H)-dione (API), which achieves a remarkable photoluminescence quantum yield (Φ PL) of 0.85 in aqueous environments and established novel AIE mechanisms. Additionally, substitution of the S-atom at the carbonyl position in RPNI-O leads to thioperylenimides (RPNI-S): 2-hexyl-8-phenyl-1H-benzo[5,10]anthra[2,1,9-def]isoquinoline-1,3(2H)-dithione (PPIS), 8-([2,2'-bithiophen]-5-yl)-2-hexyl-1H-benzo[5,10]anthra[2,1,9-def]isoquinoline-1,3(2H)-dithione (THPIS), and 2-hexyl-8-(thianthren-1-yl)-1H-benzo[5,10]anthra[2,1,9-def]isoquinoline-1,3(2H)-dithion (APIS), with distinct photophysical properties (enlarged spin-orbit coupling (SOC) and Φ PL ≈ 0.00), and developed diverse potent photosensitizers (PSs). The present work provides a novel SOC enhancement mechanism via pronounced H-aggregation. Surprisingly, the lowest singlet oxygen quantum yield (Φ Δ) and theoretical calculation suggest the specific type-I PDT for RPNI-S. Interestingly, RPNI-S efficiently produces superoxide (O2˙-) due to its remarkably lower Gibbs free energy (ΔG) values (THPIS: -40.83 kcal mol-1). The non-toxic and heavy-atom free very specific thio-based PPIS and THPIS PSs showed selective and efficient PDT under normoxia, as a rare example.

2.
Chem Asian J ; : e202400544, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38865578

RESUMO

The precise and effective detection of neurotransmitters (NTs) is crucial for clinical investigation of neuronal processes, and timely monitoring of NT-related chronic diseases. However, sensitive detection of specific NT with unprecedented selectivity is highly challenging due to similarities in chemical and electronic structures of various interfering neurochemicals. Herein, an anionic conjugated polyelectrolyte Poly[(9,9-bis(4'-sulfonatobutyl)fluorene-co-alt-1,4-phenylene) sodium], PFPS was rationally designed and synthesized for amplified detection and point-of-care (PoC) determination of monoamine neurotransmitter, serotonin (5-Hydroxy tryptamine or 5-HT, also diagnostic biomarker of carcinoid tumor) in human blood plasma. The PFPS displayed a remarkable sensing response with an exceptionally high fluorescence quenching constant of 1.14 × 105 M-1 and an ultralow detection limit of 0.67 µM or 0.142ppm, much below the clinical range (0.5-1.4 µM). Furthermore, a smartphone-enabled portable platform was constructed for real-time onsite detection of 5-HT by quantification of visual fluorescence response of PFPS into RGB values using a color recognizer android application. The smartphone platform could be readily applied for convenient, non-invasive PoC testing of 5-HT levels in complex biological fluids accurately and is expected to revolutionize clinical diagnosis and personalized health care devices.

3.
Phys Chem Chem Phys ; 26(21): 15600-15610, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38757930

RESUMO

Perylene monoimide (PMI) derivatives are attracting significant attention due to their strong absorption in the visible range, thermal stability, and synthetic accessibility. These properties make them promising for application in various areas such as optoelectronic devices, photosensitizers, etc. In this work, the photophysical properties and excited state dynamics of four different PMI derivatives (PMIB, BrPMITB, PMITB, and APITB) were studied in solution and thin films utilizing steady-state and time-resolved spectroscopic techniques. Among the four PMI derivatives, APITB is designed as a donor-acceptor dyad, with thianthrene as a donor and PMI as an acceptor. The activation of the triplet state through the spin-orbit charge transfer intersystem crossing (SOCT-ISC) process in THF was observed upon substitution with the thianthrene group at the peri position of the PMI moiety. The SOCT-ISC process facilitates triplet formation in the APITB dyad within 423 ps. Meanwhile, other PMI derivatives showed fluorescence within the femtosecond timescale in THF. The PMI derivatives in thin films displayed different photo physical properties to those in THF. This discrepancy arises due to the effective intermolecular coupling between the PMI derivatives in thin films.

4.
Small ; : e2400119, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38676344

RESUMO

Concomitant achievement of all three performance pillars of a supercapacitor device, namely gravimetric, areal, and volumetric capacitance is a grand challenge. Nevertheless, its fulfilment is indispensable for commercial usage. Although, high compactness is the fundamental requirement to achieve high volumetric performance, it severely affects ion transportation in thick electrodes. Such trade-off makes it extremely challenging to realize very high areal and volumetric performance simultaneously. Here, a collapsed hydrogel strategy is introduced to develop MXene/cellulose nanofiber (CNF) based densified electrodes that offer excellent ion transportation despite a massive increase in areal mass loading (>70 mg cm-2). Quasi-oriented MXene/CNF (MXCF) hydrogels are produced through an electric field-guided co-assembly technique. Ambient dehydration of these hydrogels incorporates numerous pores in the resultant compact electrodes due to crumpling of the MXene sheets, while CNF ensures connectivity among the locally blocked pores in different length scales. The resultant collapsed MXCF densified electrode shows a remarkably high areal capacitance of 16 F cm-2 while simultaneously displaying a high volumetric capacitance of 849.8 F cm-3 at an ultrahigh mass loading of up to 73.4 mg cm-2. The universality of strategy, including the co-assembly of hydrogel and its collapse, is further demonstrated to develop high-performance asymmetric and wearable devices.

5.
RSC Adv ; 14(11): 7915-7923, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38449822

RESUMO

Ambient stable solution processed n-channel organic field effect transistors (OFETs) are essential for next-generation low-cost organic electronic devices. Several molecular features, such as suitable orbital energy levels, easy synthetic steps, etc., must be considered while designing efficient active layer materials. Here, we report a case of improved ambient stability of solution-processed n-type OFETs upon suitable end-groups substitution of the active layer materials. A pair of core-substituted napthalenediimide (NDIFCN2 and EHNDICN2) derivatives with alkyl and perfluorinated end groups are considered. The transistor devices made out of these two derivatives exhibited largely different ambient stability behavior. The superior device stability (more than 25 days under ambient conditions) of one of the derivatives (NDIFCN2) was ascribed to the presence of fluorinated end groups that function as hydrophobic guard units inhibiting moisture infiltration into the active layer, thereby achieving ambient stability under humid conditions (>65% relative atmospheric humidity). Molecular level optical and electrochemical properties, thermal stability, and the solution-processed (spin coat and drop cast active layers) device characteristics are described in detail. Our findings highlight the requirement of hydrophobic end groups or sidechains for ambient stability of active layer materials, along with deep LUMO levels for ambient stability.

6.
Methods Mol Biol ; 2761: 337-354, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38427249

RESUMO

The gradual loss of neurons' structure and function in the central nervous system is known as neurodegeneration. It is a defining feature of several incapacitating illnesses, such as Alzheimer's disease, Parkinson's disease, and Huntington's disease. The buildup of amyloid beta (Aß) protein in the brain is one of the several variables linked to neurodegeneration. We shall delve into the fascinating realm of Aß in this chapter and examine its role in the etiology of neurodegenerative illnesses. Insights into the processes through which Aß exerts its toxicity are crucial for the creation of therapeutic approaches to treat these life-threatening diseases. Despite the presence of multiple obstacles, recent research shows promise for the development of some new anti-Aß therapies that will help millions of people suffering from neurodegeneration. In this chapter, we discuss the role of Aß in contributing to neurotoxicity and several anti-Aß therapies for neuroprotection.


Assuntos
Doença de Alzheimer , Doença de Parkinson , Humanos , Peptídeos beta-Amiloides/metabolismo , Neuroproteção/fisiologia , Doença de Alzheimer/metabolismo , Doença de Parkinson/terapia
7.
ACS Appl Bio Mater ; 7(3): 1899-1909, 2024 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-38417048

RESUMO

Harvesting triplets in metal-free organic frameworks at ambient conditions and finding appropriate applications are a formidable challenge. Herein, we report a donor-acceptor-type system composed of carbazole and fused 2H-chromene coumarin derivative, exhibiting triplet harvesting thermally activated delayed fluorescence (TADF) and aggregation-induced emission (AIE) behavior in solid and aggregated states, respectively. The presence of an sp3 linker and the introduction of a selected cyano/ester group in the acceptor result in twisted D-A architectures, further assisting in the suppression of nonradiative deactivation via through-space charge transfer and H-bonding interactions, fulfilling the stringent requirements for the simultaneous process of TADF and AIE, successively. Experimental and theoretical results revealed that the participation of the singlet/triplet charge transfer (1CT/3CT) and the higher lying hybrid triplet locally excited charge-transfer state (3LE + 3CT) leads to an efficient TADF. Both of the synthesized AIE-TADF congeners actively participated in the generation of reactive oxygen species (ROS) in nanoaggregate forms and were further explored computationally for antiviral prospects as inhibitors of the SARS-CoV-2 spike protein.


Assuntos
Benzopiranos , COVID-19 , Estruturas Metalorgânicas , Glicoproteína da Espícula de Coronavírus , Humanos , SARS-CoV-2 , Espécies Reativas de Oxigênio , Fluorescência , Cumarínicos/farmacologia , Antivirais
8.
ACS Chem Neurosci ; 15(2): 268-277, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-38170988

RESUMO

The emergence of neurodegenerative diseases is connected to several pathogenic factors, including metal ions, amyloidogenic proteins, and reactive oxygen species. Recent studies suggest that cytotoxicity is caused by the small, dynamic, and metastable nature of early stage oligomeric species. This work introduces a small molecule-based red-emitting probe with smart features such as increased reactivities against multiple targets, metal-free amyloid-ß (Aß), and metal-bound amyloid-ß (Aß), and most importantly, early stage oligomeric species which are associated with the most common and widespread type of dementia, Alzheimer's disease (AD). Theoretical analyses like molecular dynamics simulation and molecular docking were performed to confirm the reactivity of the molecule toward Aß and found some excellent interactions between the molecule and the peptide. The in vitro and cellular studies demonstrated that this highly biocompatible molecule effectively reduces the structural damage to mitochondria while shielding cells from apoptosis, scavenges ROS (reactive oxygen species), and attenuates multifaceted amyloid toxicity.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Simulação de Acoplamento Molecular , Peptídeos beta-Amiloides/metabolismo , Metais/metabolismo
9.
Analyst ; 148(23): 6011-6019, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37882495

RESUMO

Environmental water pollution caused by hexavalent chromium (Cr(VI)) is a threat to living beings due to its carcinogenic nature. Herein, we report the synthesis of a highly fluorescent water-soluble conjugated polyelectrolyte PPMI and its application as a fluorescence sensor to monitor traces of carcinogenic Cr(VI) ions in water. PPMI was synthesized via the oxidative polymerization method followed by post-polymer functionalization. Fluorescent PPMI exhibited a photoluminescence quantum yield of 23.87 and displayed a rapid, very selective, and sensitive turn-off fluorescence signal in response to Cr(VI), with a significantly high quenching constant of 1.32 × 106 M-1. The mechanism of sensing was found to be static quenching. The limit of detection of this highly accessible analytical method was found to be in nanomolar ranges, i.e. 0.85 nM. Additionally, sensing on solid platforms such as economical paper strips was successfully achieved, which is very challenging and highly recommended for any reliable, portable, and economical analytical method.

10.
Nat Commun ; 14(1): 6648, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37863932

RESUMO

Photofunctional co-crystal engineering strategies based on donor-acceptor π-conjugated system facilitates expedient molecular packing, consistent morphology, and switchable optical properties, conferring synergic 'structure-property relationship' for optoelectronic and biological functions. In this work, a series of organic co-crystals were formulated using a twisted aromatic hydrocarbon (TAH) donor and three diverse planar acceptors, resulting in color-tunable solid and aggregated state emission via variable packing and through-space charge-transfer interactions. While, adjusting the strength of acceptors, a structural transformation into hybrid stacking modes ultimately results in color-specific polymorphs, a configurational cis-isomer with very high photoluminescence quantum yield. The cis-isomeric co-crystal exhibits triplet-harvesting thermally activated delayed fluorescence (TADF) characteristics, presenting a key discovery in hydrocarbon-based multicomponent systems. Further, 1D-microrod-shaped co-crystal acts as an efficient photon-transducing optical waveguides, and their excellent dispersibility in water endows efficient cellular internalization with bright cell imaging performances. These salient approaches may open more avenues for the design and applications of TAH based co-crystals.

11.
ACS Appl Bio Mater ; 6(10): 4383-4391, 2023 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-37769186

RESUMO

Fibrillation of amyloid beta (Aß) is the key event in the amyloid neurotoxicity process that induces a chain of toxic events including oxidative stress, caspase activation, poly(ADP-ribose) polymerase cleavage, and mitochondrial dysfunction resulting in neuronal loss and memory decline manifesting as clinical dementia in humans. Herein, we report the development of a novel, biologically active supramolecular probe, INHQ, and achieve functional nanoarchitectures via a self-assembly process such that ultralong fibers are achieved spontaneously. With specifically decorated functional groups on INHQ such as imidazole, hydroxyquinoline, hydrophobic chain, and hydroxyquinoline molecules, these ultralong fibers coassembled efficiently with toxic Aß oligomers and mitigated the amyloid-induced neurotoxicity by blocking the aforementioned biochemical events leading to neuronal damage in mice. These functional ultralong "Artificial Fibers" morphologically resemble the amyloid fibers and provide a higher surface area of interaction that improves its clearance ability against the Aß aggregates. The efficacy of this novel INHQ molecule was ascertained by its high ability to interact with Aß. Moreover, this injectable, ultralong INHQ functional "artificial fiber" translocates through the blood-brain barrier and successfully attenuates the amyloid-triggered neuronal damage and pyknosis in the cerebral cortex of wild-type mouse. Utilizing various spectroscopic techniques, morphology analysis, and in vitro, in silico, and in vivo studies, these ultralong INHQ fibers are proven to hold great promise for treating neurological disorders at all stages with a potential to replace the existing medications, reduce complications in the brain, and eradicate the amyloid-triggered neurotoxicity implicated in numerous disorders in human through a rare synergistic mechanism.


Assuntos
Doença de Alzheimer , Hidroxiquinolinas , Camundongos , Humanos , Animais , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/uso terapêutico , Neurônios/metabolismo , Encéfalo/metabolismo , Amiloide , Hidroxiquinolinas/uso terapêutico
12.
Chem Sci ; 13(31): 9004-9015, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-36091201

RESUMO

Through-space donor-alkyl bridge-acceptor (D-σ-A) luminogens are developed as new organic single-molecule white light emitters (OSMWLEs) involving multiple higher lying singlet (S n ) and triplet (T m ) states (hot-excitons). Experimental and theoretical results confirm the origin of white light emission due to the co-existence of prompt fluorescence from locally excited states, thermally activated delayed fluorescence (TADF), and fast/slow dual phosphorescence color mixing simultaneously. Notably, the fast phosphorescence was observed due to trace amounts of isomeric impurities from commercial carbazole, while H-/J-aggregation resulted in slow phosphorescence. Crystal structure-packing-property analysis revealed that the alkyl chain length induced supramolecular self-assembly greatly influenced the solid-state optical properties. Remarkably, the 1D-microrod crystals of OSMWLEs demonstrated the first examples of triplet harvesting waveguides by self-guiding the generated phosphorescence through light propagation along their longitudinal axis. This work thus highlights an uncommon design strategy to achieve multi-functional OSMWLEs with in-depth mechanistic insights and optical waveguiding applications making them a potentially new class of white emissive materials.

13.
Anal Chem ; 94(30): 10685-10694, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35849826

RESUMO

Nonspecific interactions of conjugated polymers (CPs) with various proteins prove to be a major impediment for researchers when designing a suitable CP-based probe for the amplified and selective recognition of particular proteins in complex body fluids. Herein, a new strategy is presented for the precise and specific monitoring of clinically important serum albumin (SA) proteins at the nanomolar level using fluorescence resonance energy transfer (FRET)-modulated CP-surfactant ensembles as superior sensing materials. In brief, the newly designed color-tunable CP PF-DBT-Im undergoes intense aggregation with the surfactant sodium dodecyl sulfate (SDS), enabling drastic change in the emission color from violet to deep red due to intermolecular FRET. The emission of PF-DBT-Im/SDS ensembles then changed from deep red to magenta specifically on addition of SAs owing to the exclusive reverse FRET facilitated by synergistic effects of electrostatic interactions, hydrophobic forces, and the comparatively high intrinsic quantum yield of SAs. Interestingly, PF-DBT-Im itself could not differentiate SAs from other proteins, demonstrating the superiority of the PF-DBT-Im/SDS self-assembly over PF-DBT-Im. Finally, an affordable smartphone-integrated point-of-care (PoC) device is also fabricated as a proof-of-concept for the on-site and rapid monitoring of SAs, validating the potential of the system in long-term clinical applications.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Polímeros , Sistemas Automatizados de Assistência Junto ao Leito , Polímeros/química , Albumina Sérica , Tensoativos
14.
ACS Meas Sci Au ; 2(1): 23-30, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785591

RESUMO

A rare combination of dual static and dynamic fluorescence quenching mechanisms is reported, while sensing the nitroexplosive trinitrotoluene (TNT) in water by a cationic conjugated copolymer PFPy. Since the fluorophore PFPy interacts with TNT in both ground state as well as the excited states, a greater extent of interaction is facilitated between PFPy and the TNT, as a result of which the magnitude of the signal is amplified remarkably. The existence of these collective sensing mechanisms provides additional advantages to the sensing process and enhances the sensing parameters, such as LoD and highly competitive sensing processes in natural water bodies irrespective of the pH and at ambient conditions. These outcomes involving dual sensing mechanistic pathways expand the scope of developing efficient sensing probes for toxic chemical analyte and biomarker detection, preventing environmental pollution and strengthening security at sensitive locations while assisting in early diagnosis of disease biomarkers.

15.
Prog Mol Biol Transl Sci ; 185: 137-177, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34782103

RESUMO

The discovery of aggregation-induced emission (AIE) phenomenon, significantly altered the understanding of the scientific world about the luminophore aggregation. Polymers with AIE features have recently emerged as promising materials with wide range of applications in optoelectronics devices, chemosensors, bioimaging, cancer theranostics and drug delivery. By introducing the AIE active molecule into the polymer structure, novel materials encompassing the characteristics properties of both the functional materials such as excellent brightness, versatile structure modification, high biocompatibility, exceptional stability and facile processability are achieved. This chapter presents the advances in synthetic design as well as potential biological applications of AIE active polymers, beginning with a brief introduction to the AIE phenomenon. The versatile synthetic route, easier functionalization, and light up feature of the AIE active polymers offer direct visualization of the physiological processes within or outside the living organisms. This chapter also precisely describes the photodynamic therapy/photothermal therapy (PDT/PTT) with up-to-date advancement of AIE active polymer and their emerging applications in biomedical field. The AIE active Photosensitizers (PSs) are much more efficient in singlet oxygen (1O2) production than their small molecule AIE active PSs due to their enhanced inter system crossing (ISC) process and improved light-harvesting ability. Additionally, the present chapter aims to focus on all recent AIE active polymers for drug screening and drug delivery. The AIE active polymer often shows decent drug loading capacity, high stability and good biocompatibility comprising image guided drug monitoring features. Lastly, the concluding discussion reveals the future prospective of the AIE active polymers.


Assuntos
Neoplasias , Polímeros , Corantes Fluorescentes , Humanos , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes
16.
Prog Mol Biol Transl Sci ; 185: 75-112, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34782108

RESUMO

The concept of aggregation-induced emission (AIE) in purely organic luminescent molecules has drawn wide attention in the last two decades. Despite the many challenges, AIE-probes have opened versatile opportunities in many research fields. In particular, the emerging functional properties of room temperature phosphorescence (RTP) and thermally activated delayed fluorescence (TADF) have boosted the unique features of AIE luminogens (AIEgens). Thus, these luminescent materials extended the utility in sensing, imaging, optoelectronics and theranostic applications in biological field over the conventional fluorescent probe. Unlike the sensitivity of triplet state by oxygen and moisture, the long-lived phosphorescence and delayed fluorescence resulting from the enhanced intersystem crossing (ISC) and reverse intersystem crossing (RISC) from excited triplet state (T1) to excited singlet state (S1) in these luminophores gives rise to long lifetimes ranging from nanoseconds to milliseconds even up to seconds. As compared to traditional fluorescence molecules advanced AIE probes show high contrast imaging and deeper penetration depth, which have been demonstrated through near infrared I and II (NIR-I & NIR-II) fluorescence imaging, room temperature after-glow imaging and photoacoustic imaging. This chapter highlights the recent developments and principle of the efficient design of AIE probe with multi-functional properties evolved with new strategies for translational applications via fluorescence imaging, photoacoustic imaging and image-guided photodynamic/photothermal therapy (PDT/PTT) including future opportunities for AIEgens to advance the overall biomedical field.


Assuntos
Imagem Óptica , Medicina de Precisão , Corantes Fluorescentes , Humanos
17.
Langmuir ; 37(26): 8024-8036, 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34155888

RESUMO

Supramolecular self-assemblies and co-assemblies possess multiple noncovalent interactions, highly ordered structures, and multifunctional properties. Yet, the fundamental understanding of their "structure-property relationship" remains very challenging. Herein, two kinetically controlled supramolecular charge transfer (CT) complexes were conceptualized from a trimorphic molecular donor denoted as "twisted aromatic hydrocarbon" (TAH), with p-fluoranil (TFQ) and p-chloranil (TCQ) in water, organic solvent, and solvent-free methods. Elucidating their co-assembling mechanism revealed that segmentation of the TAH with molecules having planar deficient cores spontaneously formed a distinct "H-type mixed stack" and "J-type segregated stack", regulated by blue/red-shifted charge-transfer and π-π stacking including weak C-H···F and C-H···O noncovalent interactions. By utilizing the structural transformational ability of the self-assembled TAH, the mechanistic aspects for the rapid nanoscopic co-assembly formation were precisely demonstrated experimentally and theoretically. The trimorphs and co-crystals of TAH could be disassembled resulting in turn-on emission by applying various external stimuli and being repeatedly reconfigured, thus providing a unique structure-property relationship and new TAH-based materials. This unique concept offers color-specific polymorphism and CT-complex formation strategy involving a simple class of functional materials having cooperative network forming ability using the twisted molecular donor.

18.
ACS Appl Bio Mater ; 4(1): 47-70, 2021 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-35014276

RESUMO

The growth of smart wearable sensing systems has gained immense importance in the present mode of data acquisition and signaling in pharmaceutical, healthcare, and wellness industries. Presently, application of smart wearables is gaining prominence in several fitness activities, therapeutics, and diagnostic areas. Smart wearable biosensors offer real-time monitoring of physiological metrics and biomarkers that are specific to certain diseases in ambulant condition. This review offers a broad overview of the state-of-the-art progress on smart wearable biosensors focusing on applications in point of care diagnostics. A careful comparison of presently available commercial devices, implementation in clinical trials, and validation also have been highlighted in the present review. This work concludes with challenges and future prospects for scientists and engineers working in the nascent interdisciplinary field.


Assuntos
Técnicas Biossensoriais/métodos , Dispositivos Eletrônicos Vestíveis , Acelerometria , Técnicas Biossensoriais/instrumentação , Temperatura Corporal , Glucose/análise , Frequência Cardíaca , Humanos , Testes Imediatos , Energia Solar , Suor/química , Suor/metabolismo
19.
Chem Commun (Camb) ; 56(94): 14861-14864, 2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33174881

RESUMO

A strategy of conformational tweaking regulates the condensed state behavior of naphthalimide skeletal isomers (NSIs) and enhances their photophysical properties, cellular uptake and prolonged imaging capability. This salient approach results in a large Stokes shift (>120 nm), rapid cellular internalization, photobleaching resistance, and efficient bioimaging of the ribbon-like nano-assembly superior to that of its electronically similar micro-flower isomer.


Assuntos
Endocitose , Fotodegradação , Corantes Fluorescentes/química , Células HeLa , Humanos , Espécies Reativas de Oxigênio/metabolismo
20.
ACS Chem Neurosci ; 11(20): 3277-3287, 2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-32941009

RESUMO

Alzheimer's disease (AD) is an irreversible memory disorder associated with multiple neuropathological events including amyloid aggregation that triggers oxidative stress and mitochondrial dysfunction in humans. Herein, a new artificial chaperone, benzimidazole functionalized polyfluorene (PFBZ) is reported to efficiently sequester toxic amyloid beta (Aß) by binding at their 'amyloidogenic domain' (Aß16-21) with unprecedented selectivity and prevent amyloid-mediated neuronal damage in a wild-type (WT) mouse model. An accurate dose of PFBZ chaperone successfully attenuated an amyloid triggered internal hemorrhage and pyknosis in the cerebral cortex of WT mice. The structural advantage of the polymer results in an efficient Cu(II) chelation arresting a redox cycle to prevent reactive oxygen species (ROS) generation and protect mitochondria from ROS mediated damage. This was further evidenced by caspase activation and mitochondrial membrane potential (MMP) biomarkers and was complemented by brain histology and electron microscopy data which revealed that the PFBZ chaperone provided a protective coating over the amyloid surface and resists from interacting with cell membrane and prevents inducing toxicity. This conjugated polymer artificial chaperone-based nanodrug showed exceptional properties such as its multipotent and highly biocompatible nature, the first of its kind with specific amyloid (Aß16-21) targeting behavior, bioimaging, and BBB permeability with a potential to suppress amyloid triggered neurotoxicity implicated in numerous human disorders through a rare synergistic mechanism.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Camundongos , Mitocôndrias/metabolismo , Neurônios/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo
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