Titanium and Iron Oxide Nanoparticles for Cancer Therapy: Surface Chemistry and Biological Implications

Currently, cancer is among the most challenging diseases due to its ability to continuously evolve into a more complex muldimentional system, in addition to its high capability to spread to other organs and tissues. In this context, the relevance of nanobiomaterials (NBMs) for the development of new more effective and less harmful treatments is increasing. NBMs provide the possibility of combining several functionalities on a single system, expectedly in a synergic way, to better perform the treatment and cure. However, the control of properties such as colloidal stability, circulation time, pharmacokinetics, and biodistribution, assuring the concentration in specific target tissues and organs, while keeping all desired properties, tends to be dependent on subtle changes in surface chemistry. Hence, the behavior of such materials in different media/environments is of uttermost relevance and concern since it can compromise their efficiency and safety on application. Given the bright perspectives, many efforts have been focused on the development of nanomaterials fulfilling the requirements for real application. These include robust and reproducible preparation methods to avoid aggregation while preserving the interaction properties. The possible impact of nanomaterials in different forms of diagnosis and therapy has been demonstrated in the past few years, given the perspectives on how revolutionary they can be in medicine and health. Considering the high biocompatibility and suitability, this review is focused on titanium dioxide– and iron oxide–based nanoagents highlighting the current trends and main advancements in the research for cancer therapies. The effects of phenomena, such as aggregation and agglomeration, the formation of the corona layer, and how they can compromise relevant properties of nanomaterials and their potential applicability, are also addressed. In short, this review summarizes the current understanding and perspectives on such smart nanobiomaterials for diagnostics, treatment, and theranostics of diseases.

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Unconventional route to dual-shelled organolead halide perovskite nanocrystals with controlled dimensions, surface chemistry, and stabilities

Science Advances ◽

10.1126/sciadv.aax4424 ◽

2019 ◽

Vol 5 (11) ◽

pp. eaax4424 ◽

Cited By ~ 27

Author(s):

Yanjie He ◽

Young Jun Yoon ◽

Yeu Wei Harn ◽

Gill V. Biesold-McGee ◽

Shuang Liang ◽

...

Keyword(s):

Surface Chemistry ◽

Colloidal Stability ◽

Core Shell ◽

Core Diameter ◽

Perovskite Nanocrystals ◽

The Past ◽

Halide Perovskite ◽

Conventional Methods ◽

The Stability ◽

Organolead Halide

The past few years have witnessed rapid advances in the synthesis of high-quality perovskite nanocrystals (PNCs). However, despite the impressive developments, the stability of PNCs remains a substantial challenge. The ability to reliably improve stability of PNCs while retaining their individual nanometer size represents a critical step that underpins future advances in optoelectronic applications. Here, we report an unconventional strategy for crafting dual-shelled PNCs (i.e., polymer-ligated perovskite/SiO2 core/shell NCs) with exquisite control over dimensions, surface chemistry, and stabilities. In stark contrast to conventional methods, our strategy relies on capitalizing on judiciously designed star-like copolymers as nanoreactors to render the growth of core/shell NCs with controlled yet tunable perovskite core diameter, SiO2 shell thickness, and surface chemistry. Consequently, the resulting polymer-tethered perovskite/SiO2 core/shell NCs display concurrently a stellar set of substantially improved stabilities (i.e., colloidal stability, chemical composition stability, photostability, water stability), while having appealing solution processability, which are unattainable by conventional methods.

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Photochemical Synthesis of Gold and Silver Nanoparticles—A Review

Molecules ◽

10.3390/molecules26154585 ◽

2021 ◽

Vol 26 (15) ◽

pp. 4585

Author(s):

Nicole Jara ◽

Nataly S. Milán ◽

Ashiqur Rahman ◽

Lynda Mouheb ◽

Daria C. Boffito ◽

...

Keyword(s):

Silver Nanoparticles ◽

Surface Chemistry ◽

Metallic Nanoparticles ◽

Colloidal Stability ◽

Photochemical Synthesis ◽

Gold And Silver Nanoparticles ◽

Future Developments ◽

Technological Advances ◽

Experimental Parameters ◽

Sophisticated Equipment

Nanomaterials have supported important technological advances due to their unique properties and their applicability in various fields, such as biomedicine, catalysis, environment, energy, and electronics. This has triggered a tremendous increase in their demand. In turn, materials scientists have sought facile methods to produce nanomaterials of desired features, i.e., morphology, composition, colloidal stability, and surface chemistry, as these determine the targeted application. The advent of photoprocesses has enabled the easy, fast, scalable, and cost- and energy-effective production of metallic nanoparticles of controlled properties without the use of harmful reagents or sophisticated equipment. Herein, we overview the synthesis of gold and silver nanoparticles via photochemical routes. We extensively discuss the effect of varying the experimental parameters, such as the pH, exposure time, and source of irradiation, the use or not of reductants and surfactants, reagents’ nature and concentration, on the outcomes of these noble nanoparticles, namely, their size, shape, and colloidal stability. The hypothetical mechanisms that govern these green processes are discussed whenever available. Finally, we mention their applications and insights for future developments.

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A review on the production, structure, bioactivities and applications of Tremella polysaccharides

International Journal of Immunopathology and Pharmacology ◽

10.1177/20587384211000541 ◽

2021 ◽

Vol 35 ◽

pp. 205873842110005

Author(s):

Xia Ma ◽

Meng Yang ◽

Yan He ◽

Chuntao Zhai ◽

Chengliang Li

Keyword(s):

Biologically Active ◽

Research Progress ◽

Research Trend ◽

Production Structure ◽

Health States ◽

Preparation Methods ◽

The Past ◽

Structure Activity ◽

Relationship Of ◽

Active Natural

Tremella polysaccharide is known to be structurally unique and biologically active natural products, abundant and versatile in activities and applications in food industry, daily chemical industry and medicine industry. In order to improve the industrialisation of Tremella polysaccharide, the limitations of preparation and structure-activity relationship of Tremella polysaccharide were reviewed in this paper. The research progress of Tremella polysaccharide in the past 20 years was summarized from the sources, preparation methods, molecular structure, activity and application, and the research trend in the future was also prospected. The application prospect of Tremella polysaccharide in against multiple sub-health states was worth expecting.

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Macrophage-Laden Gold Nanoflowers Embedded with Ultrasmall Iron Oxide Nanoparticles for Enhanced Dual-Mode CT/MR Imaging of Tumors

Pharmaceutics ◽

10.3390/pharmaceutics13070995 ◽

2021 ◽

Vol 13 (7) ◽

pp. 995

Author(s):

Yucheng Peng ◽

Xiaomeng Wang ◽

Yue Wang ◽

Yue Gao ◽

Rui Guo ◽

...

Keyword(s):

Iron Oxide ◽

Mr Imaging ◽

Iron Oxide Nanoparticles ◽

Colloidal Stability ◽

Pamam Dendrimer ◽

Great Promise ◽

Oxide Nanoparticles ◽

Dual Mode ◽

Gold Nanoflowers ◽

Average Size

The design of multimodal imaging nanoplatforms with improved tumor accumulation represents a major trend in the current development of precision nanomedicine. To this end, we report herein the preparation of macrophage (MA)-laden gold nanoflowers (NFs) embedded with ultrasmall iron oxide nanoparticles (USIO NPs) for enhanced dual-mode computed tomography (CT) and magnetic resonance (MR) imaging of tumors. In this work, generation 5 poly(amidoamine) (G5 PAMAM) dendrimer-stabilized gold (Au) NPs were conjugated with sodium citrate-stabilized USIO NPs to form hybrid seed particles for the subsequent growth of Au nanoflowers (NFs). Afterwards, the remaining terminal amines of dendrimers were acetylated to form the dendrimer-stabilized Fe3O4/Au NFs (for short, Fe3O4/Au DSNFs). The acquired Fe3O4/Au DSNFs possess an average size around 90 nm, display a high r1 relaxivity (1.22 mM−1 s−1), and exhibit good colloidal stability and cytocompatibility. The created hybrid DSNFs can be loaded within MAs without producing any toxicity to the cells. Through the mediation of MAs with a tumor homing and immune evasion property, the Fe3O4/Au DSNFs can be delivered to tumors more efficiently than those without MAs after intravenous injection, thus significantly improving the MR/CT imaging performance of tumors. The developed MA-mediated delivery system may hold great promise for enhanced tumor delivery of other contrast agents or nanomedicines for precision cancer nanomedicine applications.

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“Economics in Command?” Ideology and Policy Since the Third Plenum, 1978–1984

The China Quarterly ◽

10.1017/s0305741000017124 ◽

1984 ◽

Vol 99 ◽

pp. 417-461 ◽

Cited By ~ 17

Author(s):

Stuart R. Schram

Keyword(s):

Policy Making ◽

Question Mark ◽

The Third ◽

The Past ◽

Great Leap ◽

Current Trends

In this article, I shall attempt to give an overview of the most important political and ideological developments during the past six years, and in this context, to assess current trends in China. The three-word title is, of course, deliberately modelled on the Great Leap slogan “Politics in command”, and is intended to evoke the problem of whether or not policy-making since 1978 has been largely shaged by economic realities, and/or by the economic goals of the, leadership I have placed a question mark after it because, though I shall certainly express some opinions on this topic before I have done, I doubt that the issue can as yet be regarded as finally settled.

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Influence of Serum Supplemented Cell Culture Medium on Colloidal Stability of Polymer Coated Iron Oxide and Polystyrene Nanoparticles With Impact on Cell Interactions In Vitro

IEEE Transactions on Magnetics ◽

10.1109/tmag.2012.2222634 ◽

2013 ◽

Vol 49 (1) ◽

pp. 402-407 ◽

Cited By ~ 7

Author(s):

Vera Hirsch ◽

Jatuporn Salaklang ◽

Barbara Rothen-Rutishauser ◽

Alke Petri-Fink

Keyword(s):

Cell Culture ◽

Iron Oxide ◽

Culture Medium ◽

Colloidal Stability ◽

Cell Interactions ◽

Cell Culture Medium ◽

Polystyrene Nanoparticles

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Current Trends in Dental Composites

Critical Reviews in Oral Biology & Medicine ◽

10.1177/10454411950060040301 ◽

1995 ◽

Vol 6 (4) ◽

pp. 302-318 ◽

Cited By ~ 249

Author(s):

J.L. Ferracane

Keyword(s):

Wear Resistance ◽

Clinical Performance ◽

Color Stability ◽

Dental Composites ◽

Filler Materials ◽

Posterior Teeth ◽

The Past ◽

Current Trends ◽

Dentin Adhesives ◽

High Concentrations

The clinical performance of dental composites has been significantly improved over the past decade through modifications in formulation that include: using more stable polymerization promoters for greater color stability; incorporating high concentrations of finely ground fillers to produce adequate strength and excellent wear resistance while retaining translucency ; adding radiopacifying agents for improved diagnostics; and utilizing dentin adhesives. However, there are problems which limit the use of composites, especially in posterior teeth. The materials remain very technique-sensitive, due to the extensive contraction which accompanies polymerization and negatively influences marginal sealing. In addition, the materials are generally considered to have inadequate mechanical properties and wear resistance in contact areas to serve as total replacements for amalgams. Current efforts are focusing on several areas, including the development of non- or minimally-shrinking dental composites containing spiro-orthocarbonates as additives to dimethacrylates or epoxy-base resins, and the production of alternative filler materials for ideal wear resistance and esthetics. This paper reviews the composition and characteristics of current dental composites, as well as recent areas of study.

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The Effect of pH and Viscosity on Magnetophoretic Separation of Iron Oxide Nanoparticles

Magnetochemistry ◽

10.3390/magnetochemistry7060080 ◽

2021 ◽

Vol 7 (6) ◽

pp. 80

Author(s):

Leonie Wittmann ◽

Chiara Turrina ◽

Sebastian P. Schwaminger

Keyword(s):

Iron Oxide ◽

Iron Oxide Nanoparticles ◽

Colloidal Stability ◽

Downstream Processing ◽

Physicochemical Characteristics ◽

Particle Migration ◽

Aggregation Behavior ◽

Oxide Nanoparticles ◽

Separation Processes ◽

Effect Of Ph

Magnetic nanoparticles (MNPs) are used for magnetophoresis-based separation processes in various biomedical and engineering applications. Essential requirements are the colloidal stability of the MNPs and the ability to be separated even in low magnetic field gradients. Bare iron oxide nanoparticles (BIONs) with a diameter of 9.2 nm are synthesized via coprecipitation, exhibiting a high saturation magnetization of 70.84 Am2 kg−1 and no remanence. In our study, zeta potential, dynamic light scattering (DLS), and sedimentation analysis show that the aggregation behavior of BIONs is influenced by pH and viscosity. Small aggregate clusters are formed with either low or high pH values or increased viscosity. Regarding magnetophoresis-based separation, a higher viscosity leads to lower magnetophoretic velocities, similar to how small aggregates do. Additionally, cooperative magnetophoresis, the joint motion of strongly interacting particles, affects the separation of the BIONs, too. Our study emphasizes the effect of pH and viscosity on the physicochemical characteristics of MNPs, resulting in different aggregation behavior. Particularly, for high viscous working media in downstream processing and medicine, respectively, the viscosity should be taken into account, as it will affect particle migration.

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LAPONITE®-stabilized iron oxide nanoparticles for in vivo MR imaging of tumors

Biomaterials Science ◽

10.1039/c5bm00508f ◽

2016 ◽

Vol 4 (3) ◽

pp. 474-482 ◽

Cited By ~ 24

Author(s):

Ling Ding ◽

Yong Hu ◽

Yu Luo ◽

Jianzhi Zhu ◽

Yilun Wu ◽

...

Keyword(s):

Iron Oxide ◽

Mr Imaging ◽

Iron Oxide Nanoparticles ◽

Colloidal Stability ◽

Coprecipitation Method ◽

Oxide Nanoparticles

LAPONITE®-stabilized iron oxide nanoparticles with great colloidal stability and high T2 relaxivity are synthesized by a facile controlled coprecipitation method, and can significantly enhance the contrast of tumors in vivo, indicating their tremendous potential in MR imaging applications.

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