Fluorescent Gold Nanoclusters for Biosensor and Bioimaging Application

Nanocelluloses (NCs), with their remarkable characteristics, have proven to be one of the most promising “green” materials of our times and have received special attention from researchers in nanomaterials. A diversity of new functional materials with a wide range of biomedical applications has been designed based on the most desirable properties of NCs, such as biocompatibility, biodegradability, and their special physicochemical properties. In this context and under the pressure of rapid development of this field, it is imperative to synthesize the successes and the new requirements in a comprehensive review. The first part of this work provides a brief review of the characteristics of the NCs (cellulose nanocrystals—CNC, cellulose nanofibrils—CNF, and bacterial nanocellulose—BNC), as well as of the main functional materials based on NCs (hydrogels, nanogels, and nanocomposites). The second part presents an extensive review of research over the past five years on promising pharmaceutical and medical applications of nanocellulose-based materials, which have been discussed in three important areas: drug-delivery systems, materials for wound-healing applications, as well as tissue engineering. Finally, an in-depth assessment of the in vitro and in vivo cytotoxicity of NCs-based materials, as well as the challenges related to their biodegradability, is performed.

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Pillar[5]arene-Modified Gold Nanorods as Nanocarriers for Multi-Modal Imaging-Guided Synergistic Photodynamic-Photothermal Therapy

10.26434/chemrxiv.13166807.v1 ◽

2020 ◽

Author(s):

Nan Song ◽

Zhijun Zhang ◽

Peiying Liu ◽

Dihua Dai ◽

Chao Chen ◽

...

Keyword(s):

Photothermal Therapy ◽

High Performance ◽

Tumor Imaging ◽

Photoacoustic Imaging ◽

Functional Materials ◽

Ros Generation ◽

Cancer Therapies ◽

New Strategy

Supramolecular approaches have opened up vast possibilities in the construction of versatile functional materials, especially those with stimuli-responsiveness and integrated functionalities of multi-modal diagnosis and synergistic therapeutics. In this study, a hybrid theranostic nanosystem named TTPY-PyÌCP5@AuNR is constructed via facile host-guest interactions, where TTPY-Py is a photosensitizer with aggregation-induced emission and CP5@AuNR represents the carboxylatopillar[5]arene (CP5)-modified Au nanorods. TTPY-PyÌCP5@AuNR integrates the respective advantages of TTPY-Py and CP5@AuNR such as the high performance of reactive oxygen species (ROS) generation and photothermal conversion, and meanwhile shows fluorescence responses to both temperature and pH stimuli due to the non-covalent interactions. The successful modification of CP5 macrocycles on AuNRs surfaces can eliminate the cytotoxicity of AuNRs and enable them to serve as the nanocarrier of TTPY-Py for further theranostic application. Significantly, both in vitro and in vivo evaluations demonstrate that this supramolecular nanotheranostic system possesses multiple phototheranostic modalities including intensive fluorescence imaging (FLI), photoacoustic imaging (PAI), efficient photodynamic therapy (PDT), and photothermal therapy (PTT), indicating its great potentials for FLI-PAI imaging-guided synergistic PDT-PTT therapy. Besides, TTPY-Py can be released from the nanocarriers upon activating by the acidic environment of lysosomes and then specifically light up mitochondria. This study brings up a new strategy into the design of versatile nanotheranostics for accurate tumor imaging and cancer therapies.

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Pillar[5]arene-Modified Gold Nanorods as Nanocarriers for Multi-Modal Imaging-Guided Synergistic Photodynamic-Photothermal Therapy

10.26434/chemrxiv.13166807 ◽

2020 ◽

Author(s):

Nan Song ◽

Zhijun Zhang ◽

Peiying Liu ◽

Dihua Dai ◽

Chao Chen ◽

...

Keyword(s):

Photothermal Therapy ◽

High Performance ◽

Tumor Imaging ◽

Photoacoustic Imaging ◽

Functional Materials ◽

Ros Generation ◽

Cancer Therapies ◽

New Strategy

Supramolecular approaches have opened up vast possibilities in the construction of versatile functional materials, especially those with stimuli-responsiveness and integrated functionalities of multi-modal diagnosis and synergistic therapeutics. In this study, a hybrid theranostic nanosystem named TTPY-PyÌCP5@AuNR is constructed via facile host-guest interactions, where TTPY-Py is a photosensitizer with aggregation-induced emission and CP5@AuNR represents the carboxylatopillar[5]arene (CP5)-modified Au nanorods. TTPY-PyÌCP5@AuNR integrates the respective advantages of TTPY-Py and CP5@AuNR such as the high performance of reactive oxygen species (ROS) generation and photothermal conversion, and meanwhile shows fluorescence responses to both temperature and pH stimuli due to the non-covalent interactions. The successful modification of CP5 macrocycles on AuNRs surfaces can eliminate the cytotoxicity of AuNRs and enable them to serve as the nanocarrier of TTPY-Py for further theranostic application. Significantly, both in vitro and in vivo evaluations demonstrate that this supramolecular nanotheranostic system possesses multiple phototheranostic modalities including intensive fluorescence imaging (FLI), photoacoustic imaging (PAI), efficient photodynamic therapy (PDT), and photothermal therapy (PTT), indicating its great potentials for FLI-PAI imaging-guided synergistic PDT-PTT therapy. Besides, TTPY-Py can be released from the nanocarriers upon activating by the acidic environment of lysosomes and then specifically light up mitochondria. This study brings up a new strategy into the design of versatile nanotheranostics for accurate tumor imaging and cancer therapies.

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Biosynthesis of fluorescent gold nanoclusters for in vitro and in vivo tumor imaging

Optics Communications ◽

10.1016/j.optcom.2015.07.023 ◽

2015 ◽

Vol 355 ◽

pp. 567-574 ◽

Cited By ~ 13

Author(s):

Linlin Li ◽

Xi Liu ◽

Changhui Fu ◽

Longfei Tan ◽

Huiyu Liu

Keyword(s):

Tumor Imaging ◽

Gold Nanoclusters

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Patients with fever of unknown origin (FUO): diagnosis by nuclear medicine imaging

Nuklearmedizin ◽

10.1055/s-0038-1623872 ◽

2001 ◽

Vol 40 (03) ◽

pp. 59-70 ◽

Cited By ~ 13

Author(s):

W. Becker ◽

J. Meiler

Keyword(s):

Nuclear Medicine ◽

Fever Of Unknown Origin ◽

Tumor Imaging ◽

White Blood Cells ◽

Unknown Origin ◽

Final Diagnosis ◽

Recurrent Fever ◽

Nuclear Medicine Imaging

SummaryFever of unknown origin (FUO) in immunocompetent and non neutropenic patients is defined as recurrent fever of 38,3° C or greater, lasting 2-3 weeks or longer, and undiagnosed after 1 week of appropriate evaluation. The underlying diseases of FUO are numerous and infection accounts for only 20-40% of them. The majority of FUO-patients have autoimmunity and collagen vascular disease and neoplasm, which are responsible for about 50-60% of all cases. In this respect FOU in its classical definition is clearly separated from postoperative and neutropenic fever where inflammation and infection are more common. Although methods that use in-vitro or in-vivo labeled white blood cells (WBCs) have a high diagnostic accuracy in the detection and exclusion of granulocytic pathology, they are only of limited value in FUO-patients in establishing the final diagnosis due to the low prevalence of purulent processes in this collective. WBCs are more suited in evaluation of the focus in occult sepsis. Ga-67 citrate is the only commercially available gamma emitter which images acute, chronic, granulomatous and autoimmune inflammation and also various malignant diseases. Therefore Ga-67 citrate is currently considered to be the tracer of choice in the diagnostic work-up of FUO. The number of Ga-67-scans contributing to the final diagnosis was found to be higher outside Germany than it has been reported for labeled WBCs. F-l 8-2’-deoxy-2-fluoro-D-glucose (FDG) has been used extensively for tumor imaging with PET. Inflammatory processes accumulate the tracer by similar mechanisms. First results of FDG imaging demonstrated, that FDG may be superior to other nuclear medicine imaging modalities which may be explained by the preferable tracer kinetics of the small F-l 8-FDG molecule and by a better spatial resolution of coincidence imaging in comparison to a conventional gamma camera.

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Occupational Exposure to Carbon Nanotubes and Carbon Nanofibres: More Than a Cobweb

Nanomaterials ◽

10.3390/nano11030745 ◽

2021 ◽

Vol 11 (3) ◽

pp. 745

Author(s):

Enrico Bergamaschi ◽

Giacomo Garzaro ◽

Georgia Wilson Jones ◽

Martina Buglisi ◽

Michele Caniglia ◽

...

Keyword(s):

Carbon Nanotubes ◽

Animal Studies ◽

Chemical Properties ◽

Biological Behavior ◽

Cross Sectional ◽

Carbon Nanofibres ◽

Material Entity ◽

Cross Sectional Design

Carbon nanotubes (CNTs) and carbon nanofibers (CNFs) are erroneously considered as singular material entities. Instead, they should be regarded as a heterogeneous class of materials bearing different properties eliciting peculiar biological outcomes both in vitro and in vivo. Given the pace at which the industrial production of CNTs/CNFs is increasing, it is becoming of utmost importance to acquire comprehensive knowledge regarding their biological activity and their hazardous effects in humans. Animal studies carried out by inhalation showed that some CNTs/CNFs species can cause deleterious effects such as inflammation and lung tissue remodeling. Their physico-chemical properties, biological behavior and biopersistence make them similar to asbestos fibers. Human studies suggest some mild effects in workers handling CNT/CNF. However, owing to their cross-sectional design, researchers have been as yet unable to firmly demonstrate a causal relationship between such an exposure and the observed effects. Estimation of acceptable exposure levels should warrant a proper risk management. The aim of this review is to challenge the conception of CNTs/CNFs as a single, unified material entity and prompt the establishment of standardized hazard and exposure assessment methodologies able to properly feeding risk assessment and management frameworks.

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Characterization of the SARS-CoV-2 coronavirus X4-like accessory protein

Egyptian Journal of Medical Human Genetics ◽

10.1186/s43042-021-00160-1 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Olanrewaju Ayodeji Durojaye ◽

Nkwachukwu Oziamara Okoro ◽

Arome Solomon Odiba

Keyword(s):

Rapid Development ◽

Protein A ◽

The Novel ◽

Quality Model ◽

A Value ◽

Model Protein ◽

Novel Coronavirus ◽

Global Threat

Abstract Background The novel coronavirus SARS-CoV-2 is currently a global threat to health and economies. Therapeutics and vaccines are in rapid development; however, none of these therapeutics are considered as absolute cure, and the potential to mutate makes it necessary to find therapeutics that target a highly conserved regions of the viral structure. Results In this study, we characterized an essential but poorly understood coronavirus accessory X4 protein, a core and stable component of the SARS-CoV family. Sequence analysis shows a conserved ~ 90% identity between the SARS-CoV-2 and previously characterized X4 protein in the database. QMEAN Z score of the model protein shows a value of around 0.5, within the acceptable range 0–1. A MolProbity score of 2.96 was obtained for the model protein and indicates a good quality model. The model has Ramachandran values of φ = − 57o and ψ = − 47o for α-helices and values of φ = − 130o and ψ = + 140o for twisted sheets. Conclusions The protein data obtained from this study provides robust information for further in vitro and in vivo experiment, targeted at devising therapeutics against the virus. Phylogenetic analysis further supports previous evidence that the SARS-CoV-2 is positioned with the SL-CoVZC45, BtRs-BetaCoV/YN2018B and the RS4231 Bat SARS-like corona viruses.

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Insights in Behavior of Variably Formulated Alginate-Based Microcapsules for Cell Transplantation

BioMed Research International ◽

10.1155/2015/965804 ◽

2015 ◽

Vol 2015 ◽

pp. 1-11 ◽

Cited By ~ 11

Author(s):

Pia Montanucci ◽

Silvia Terenzi ◽

Claudio Santi ◽

Ilaria Pennoni ◽

Vittorio Bini ◽

...

Keyword(s):

Divalent Cations ◽

Chemical Properties ◽

Live Cells ◽

High Performing ◽

Physical Chemical ◽

Degenerative Disorders ◽

Selection Of ◽

Better Than

Alginate-based microencapsulation of live cells may offer the opportunity to treat chronic and degenerative disorders. So far, a thorough assessment of physical-chemical behavior of alginate-based microbeads remains cloudy. A disputed issue is which divalent cation to choose for a high performing alginate gelling process. Having selected, in our system, high mannuronic (M) enriched alginates, we studied different gelling cations and their combinations to determine their eventual influence on physical-chemical properties of the final microcapsules preparation,in vitroandin vivo. We have shown that used of ultrapure alginate allows for high biocompatibility of the formed microcapsules, regardless of gelation agents, while use of different gelling cations is associated with corresponding variable effects on the capsules’ basic architecture, as originally reported in this work. However, only the final application which the capsules are destined to will ultimately guide the selection of the ideal, specific gelling divalent cations, since in principle there are no capsules that are better than others.

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Synthesis, Characterization and Evaluation of Peptide Nanostructures for Biomedical Applications

Molecules ◽

10.3390/molecules26154587 ◽

2021 ◽

Vol 26 (15) ◽

pp. 4587

Author(s):

Fanny d’Orlyé ◽

Laura Trapiella-Alfonso ◽

Camille Lescot ◽

Marie Pinvidic ◽

Bich-Thuy Doan ◽

...

Keyword(s):

Amino Acids ◽

Biomedical Applications ◽

Chemical Reactivity ◽

Physical Stability ◽

Chemical Properties ◽

Building Blocks ◽

Imaging Probes ◽

Therapeutic Molecules

There is a challenging need for the development of new alternative nanostructures that can allow the coupling and/or encapsulation of therapeutic/diagnostic molecules while reducing their toxicity and improving their circulation and in-vivo targeting. Among the new materials using natural building blocks, peptides have attracted significant interest because of their simple structure, relative chemical and physical stability, diversity of sequences and forms, their easy functionalization with (bio)molecules and the possibility of synthesizing them in large quantities. A number of them have the ability to self-assemble into nanotubes, -spheres, -vesicles or -rods under mild conditions, which opens up new applications in biology and nanomedicine due to their intrinsic biocompatibility and biodegradability as well as their surface chemical reactivity via amino- and carboxyl groups. In order to obtain nanostructures suitable for biomedical applications, the structure, size, shape and surface chemistry of these nanoplatforms must be optimized. These properties depend directly on the nature and sequence of the amino acids that constitute them. It is therefore essential to control the order in which the amino acids are introduced during the synthesis of short peptide chains and to evaluate their in-vitro and in-vivo physico-chemical properties before testing them for biomedical applications. This review therefore focuses on the synthesis, functionalization and characterization of peptide sequences that can self-assemble to form nanostructures. The synthesis in batch or with new continuous flow and microflow techniques will be described and compared in terms of amino acids sequence, purification processes, functionalization or encapsulation of targeting ligands, imaging probes as well as therapeutic molecules. Their chemical and biological characterization will be presented to evaluate their purity, toxicity, biocompatibility and biodistribution, and some therapeutic properties in vitro and in vivo. Finally, their main applications in the biomedical field will be presented so as to highlight their importance and advantages over classical nanostructures.

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Protein-templated gold nanoclusters as specific bio-imaging probes for the detection of Hg(ii) ions in in vivo and in vitro systems: discriminating between MDA-MB-231 and MCF10A cells

The Analyst ◽

10.1039/d0an02108c ◽

2021 ◽

Author(s):

Subhajit Chakraborty ◽

Atanu Nandy ◽

Subhadip Ghosh ◽

Nirmal Kumar Das ◽

Sameena Parveen ◽

...

Keyword(s):

Breast Cancer ◽

Human Serum Albumin ◽

Gold Nanoclusters ◽

Selective Detection ◽

Imaging Probes ◽

Bio Imaging ◽

In Vitro Systems ◽

Mcf10a Cells

Sub-nanomolar selective detection of Hg(ii) ions by protein (Human Serum Albumin, HSA) templated gold nanoclusters (AuNCs), both in in vitro as well as in vivo environments and specific endocytose behaviour towards breast cancer (BC) cell lines.

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