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We present the structure of a new tetranuclear titanium oxo complex containing the antibacterial agent triclosan. This provides a good model for the interaction between triclosan and titania, which may be used for drug-delivery applications. The antibacterial activity of the hydrolyzed complex against Staphylococcus aureus is investigated. Thereafter, we use the obtained titanium oxo complex to demonstrate its susceptibility towards hydrolysis, contrary to the widespread belief that titanium oxo complexes are water-stable, and demonstrate that it transforms into titania (anatase) on contact with water. Both hydrolysis and thermolysis of the complex yield titania particles, of very uniform size and shape, that connect into 3D nanostructures; this is of interest for practical applications. [ABSTRACT FROM AUTHOR]

One major focus of antitumor drug delivery is the development of suitable carriers for therapeutic molecules. Superparamagnetic iron oxide nanoparticles are promising magnetic drug carriers as they are biocompatible, biodegradable, readily tunable, superparamagnetic, and, thus, controllable by an external magnetic field. In this paper, we propose and demonstrate a bioinspired synthesis of polydopamine-functionalized superparamagnetic magnetite nanocrystal clusters for antitumor drug delivery. Firstly, an oil-phase evaporation-induced self-assembly strategy was introduced to fabricate magnetite nanocrystal clusters (MNCs), which have the advantage of increased magnetization through a synergistic effect. Secondly, the surface functionalization of the MNCs with polydopamine (PDOPA) was demonstrated. Thirdly, the antitumor drug epirubicin (EPB) was attached to the surface of MNC@PDOPA, and its applicability for use as a magnetically guided carrier for antitumor drug delivery was demonstrated. The achieved MNC@PDOPA exhibits superparamagnetic characteristics, improved magnetization behavior under an external magnetic field, well-controlled loading, and pH-responsive properties; therefore, the MNC@PDOPA is a promising nanomaterial for in vivo EPB delivery applications and tumor chemotherapy. [ABSTRACT FROM AUTHOR]

Although metal-organic frameworks (MOFs) have been widely demonstrated to be great candidates for drug delivery applications, they have been mainly proposed for the intravenous route. Here, eight highly porous benchmarked MOFs, with different topologies and structures, are proposed for the topical delivery of salicylic acid (SA), an important, but highly reactive and unstable, therapeutically active metabolite of aspirin. The microporous Zr aminoterephthalate UiO-66-NH2 was selected as the most promising SA carrier, achieving important loadings (12.1 wt.%). Finally, the SA delivery process was studied under simulated cutaneous conditions (aqueous media at 37°C), reaching a plateau in 6 h (with ~64% or ~105.6 mg of released SA per g of UiO-66-NH2). These results demonstrate the suitability of UiO-66-NH2 for the topical controlled release of SA, making this formulation a promising candidate for the development of new devices for skin treatment. [ABSTRACT FROM AUTHOR]

This paper reports a new approach towards the construction of a multifunctional periodic mesoporous organosilica (PMO), which integrates a range of advantages, such as mesoporous structural order, selective nucleobase-recognition properties, stimuli-responsive site-specific delivery of anticancer agents to cancer tissues, and Cu2+ adsorption, into a single entity. First, the appropriate organic-functional-receptor precursor was synthesized by a chemical process and used to fabricate a multifunctional pyridine-containing PMO material (DMPy-PMO) by a hydrolysis and condensation route. The designed organic-inorganic hybrid mesoporous silica chemosensor showed an intrinsic selective recognition of nucleobase, specifically thymidine, through multipoint hydrogen-bonding interactions with suitably arrayed receptor sites loaded into the rigid silica framework. An in vitro cytotoxicity test showed that the designed chemosensor materials have good biocompatibility and, therefore, could be promising candidates for the delivery of a range of therapeutic agents. Confocal laser scanning microscopy (CLSM) confirmed that the material can be internalized effectively by cancer cells (MCF-7 cells). In addition, the DMPy-PMOs showed efficient Cu2+ ion removal capacity at pH 5.0 with significantly high levels of adsorption (0.95 mmol g-1). These results suggest that the prepared multifunctional PMO hybrid has potential use as a smart material for a range of applications, such as biomolecule recognition, biomedical applications, and as an efficient adsorbent for the removal of metal ions. [ABSTRACT FROM AUTHOR]

A novel GNRs@mSiO2 core–shell nanocomposite has been synthesized to integrate sensitive chemotherapy with photodynamic therapy (PDT) and photothermal therapy (PTT) for enhanced antitumor treatment by using gold nanorods (GNRs) as the core and mesoporous silica (mSiO2) as the shell. After modifying with ‐NH2, Indocyanine Green (ICG, negative charge) and doxorubicin hydrochloride (DOX, positive charge) molecules could be stored in the mesopores by the layer‐by‐layer assembly method through electrostatic interactions. To inhibit leakage from the mesopores, a sensitive Se–Se linker was synthesized and adopted as a nanovalve coated on the outside of the nanoparticles (GNRs@mSiO2‐ICG‐DOX@Se‐Se). Under NIR (808 nm) irradiation, heat elevation (derived from GNR/ICG) and generation of reactive oxygen species (ROS, derived from ICG) can also be detected in vitro. Owing to the redox sensitivity of Se–Se, GNRs@mSiO2‐ICG‐DOX@Se‐Se showed reduction (GSH)‐ as well as oxidation (ROS)‐triggered DOX release. To further ensure specific targeting, folic acid (FA) was grafted to the outside of the nanoparticles, because of the high expression of FA receptors on tumor cells. Detailed cell experiments performed with the nanoparticles and HepG2 as typical cancer cells showed enhanced cytotoxicity towards the cancer cells owing to the synergistic effect of chemotherapy, PTT, and PDT. On account of the different GSH concentrations in cancer and normal cells and the switch‐on/off application of NIR irradiation, the GNRs@mSiO2‐ICG‐DOX@Se‐Se‐FA nanoparticles show potential for applications in cancer therapy. GNRs@mSiO2 core–shell nanoparticles have been synthesized as host to load ICG and DOX molecules by the layer‐by‐layer assembly method through electrostatic interactions. A sensitive Se–Se linker was synthesized and grafted to ensure controlled release. Under NIR irradiation, the enhanced cytotoxicity to cancer cells is derived from the synergistic effect of chemotherapy, PTT, and PDT. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) have attracted a great deal of attention in the areas of biomedicine due to their versatile porous structures and are potentially ideal vehicles for loading bioactive molecules and controlling the release of small molecules. Current approaches for encapsulation of drug molecules in MOFs are usually based on multistep wet processes. We report here a novel simple and rapid solid‐state process that combines the mechanosynthesis of HKUST‐1 and the encapsulation of ibuprofen (IBU‐H), as a model drug molecule, in a one‐pot reaction involving a pre‐assembled [Cu2(IBU)4]·2DMF cluster. The ibuprofen‐loaded MOF composite (with 58.5 wt.‐% loading capacity) was also studied as a drug delivery carrier system in phosphate buffered saline (PBS) solution at 37 °C. [ABSTRACT FROM AUTHOR]

Square‐planar bis(dithiolene) complexes are characterized with a planar delocalized structure and a strong and tunable near infrared (NIR) absorption; they are highly stable under laser irradiation, and their conversion efficiency (light to heat) reaches up to 40–50 %. Their involvement in soft matter, namely liquid crystals, gels, and nanoparticles, opens many possibilities to control the actual state of a material, particularly under light irradiation. Thus, liquid crystalline phases can easily be modified, (i) with temperature to modulate the extended magnetic interactions of paramagnetic complexes, or (ii) under laser irradiation to unravel these remarkable photothermal properties, toward the development of light‐responsive materials. Dithiolene complexes can be also functionalized to produce very effective gelation agents, while the photothermal effect can be used to destabilize at will their supramolecular organization. Besides photothermal therapy, new therapeutic agents were also developed for photo‐controlled drug delivery and bioimaging, combining chemotherapy and phototherapy. Hydrophobic complexes were accordingly designed for their encapsulation in block copolymer nanoparticles for photothermal therapy and photo‐controlled drug delivery under laser irradiation. This class of complexes can be also used as exogenous contrast agents for photoacoustic bioimaging. [ABSTRACT FROM AUTHOR]

The search for new CoIII‐based drug delivery systems has attracted considerable attention in recent years. In this work, two cobalt complexes with general formula [Co(L)Am](ClO4)n were synthesized, in which L– = (ethyl‐3‐(7‐(diethylamino)‐2‐oxo‐2H‐chromen‐3‐yl)‐3‐oxopropanoate), a coumarin‐β‐keto ester ligand, and Am is the auxiliary amine TPA (tris‐(2‐pyridylmethyl)amine) or Py2en (2‐pyridylmethyl)‐1,2‐diamine). Complexation reactions yielded [CoII(L)TPA]ClO4(1) and [CoIII(L)Py2en](ClO4)2(2), and the CoIII complex (2) was investigated as a potential hypoxia‐activated prodrug prototype. The redox potential of the CoIII/CoII couple (+ 0.152 V vs. standard hydrogen electrode – SHE) was outside the suggested range for activation by cellular reductases. However, (2) was successfully able to release L– in the presence of sodium ascorbate, which was found to be slightly dependent on the O2 concentration. In terms of cytotoxicity, (2) and HL were the least toxic compounds against the tumor cells tested (IC50 > 40 and 100 µm) and nontoxic against normal cells. The results show that complex (2) is a reductively activated non‐toxic carrier system. [ABSTRACT FROM AUTHOR]

Two novel cobalt(III) complexes, [Co(TPA)(TCC)]ClO4·H2O (1) and [Co(py2en)(TCC)]ClO4·2H2O (2), were synthesized and fully characterized by IR, UV/Vis and 1H NMR spectroscopy, ESI mass spectrometry, and X‐ray diffraction. Cyclic voltammetry experiments revealed an irreversible reduction of the Co3+ center for both complexes. The Co3+/Co2+ redox potential, –0.91 V for 1 and –1.15 V for 2 (vs. Fc/Fc+), was obtained by square wave voltammetry in DMSO. Reactions of 1 and 2 with ascorbic acid and sodium dithionite at pH 7.4 and 6.2 were carried out in argon and open‐air atmospheres, to simulate biological redox activation under hypoxia and normoxia. Neither the Co3+/Co2+ reduction nor the dissociation of TCC2– was observed. Thermodynamic parameters calculated for the Co3+/Co2+ reduction and substitution of the TCC2– ligand by water indicate an endothermic non‐spontaneous reaction. The two CoII‐TCC complexes are unreactive regarding ligand exchange in DMSO, aqueous solutions, or in the presence of reducing agents. The Co3+/Co2+ potential (–0.91 and –1.15 V vs. Fc/Fc+) denotes the stability of the +3 oxidation state. The calculated Gibbs free energy for the Co3+/Co2+ reduction followed by the substitution of TCC2– by water points to non‐spontaneous endothermic reactions. [ABSTRACT FROM AUTHOR]

Novel organic‐inorganic polyoxometalates (POMs) decorated with covalent fluorescent tags have been designed for cell internalization. Their localization within model HEK cells is readily accomplished by confocal fluorescence microscopy. While cell internalization is dictated by the formation of the amphiphilic POM‐based nanostructures, their cytoplasmic‐nuclear trafficking appears to be regulated by a subtle interplay of the organic‐inorganic domains of the nanoassemblies which, in turn, impacts their dynamic behavior and capability to interact with cell membranes. Polyoxometalates with appended fluorescent tags form nanoparticles that can internalize into cells, with a localization depending on their composition. [ABSTRACT FROM AUTHOR]

The use of silver as an antibacterial agent has seen renewed interest as a result of its ability to combat a broad range of bacterial species, including those resistant to multiple classes of antibiotics. Silver coordination polymers (CPs) provide the opportunity to control the release of silver ions, thus avoiding unwanted side effects and toxicity; however, the parameters that tune release remain poorly understood. Here, four silver CPs, namely [Ag2(Me4bpz)] as both four‐ and eightfold interpenetrated forms, and [Ag(dpzm)(ClO4)] in its open 3D and close‐packed 2D forms, were used to probe the role of structure in the release of silver ions. Release was measured by inductively‐coupled plasma mass spectrometry (ICP‐MS) and shown to be more marked for the charged networks, [Ag(dpzm)(ClO4)] (complete dissolution). Incorporation of the silver CPs into inert polymer matrices, polyethylene and polycaprolactone, to provide surface coatings was also investigated, and shown to significantly retard silver ion release. The antibacterial activities of all materials as their polymer composites were analysed by disk diffusion and bacterial growth assays. All CPs showed antibacterial activity, with the Gram‐positive Staphylococcus aureus exhibiting greater sensitivity to silver than the Gram‐negative Escherichia coli. Metal–ligand bond strength and anion availability were found to influence silver release into aqueous solution but this did not always correlate with the in vitro antibacterial activity. [ABSTRACT FROM AUTHOR]

The motivation of this work was to probe whether coordination of esculetin to cobalt(III) could lead to a complex with the required properties to function as a redox-activated drug delivery platform, selective for hypoxic environments. The complex [Co(esc)(py2en)]ClO4·(CH3OH)2 (1) was obtained and fully characterized by CHN elemental analysis, single-crystal Xray diffractometry, UV/Vis and fluorescence spectroscopy, and ESI mass spectrometry. The redox behavior of 1 was evaluated by cyclic and square wave voltammetry analyses in MeCN and PBS buffer, which revealed distinct potentials for the Co3+/Co2+ processes in aqueous and organic solutions. In PBS, the potential is within the accepted ideal range (-0.2 to -0.4 V vs. SHE) for reduction in biological systems. Thus, a selective release of the coumarin ligand in a hypoxic environment upon reduction was simulated by investigating reactions of 1 with sodium dithionite in argon-, air-, and O2-saturated atmospheres. An [O2]-dependent dissociation of esculetin was monitored over a 72 h period at 25 °C by UV/Vis spectroscopy and confirmed by fluorescence spectroscopy and ESI-MS data. These results provide strong evidence of a hypoxia-selective, redox-activated mechanism for the release of esculetin from this cobalt(III) complex. [ABSTRACT FROM AUTHOR]

A ruthenium–nitrosyl derivative of formula [RuII(CzT)(bipy)(NO)](PF6)3 [CzT = 4′‐(N‐ethylcarbazol‐3‐yl)‐2,2′:6′,2′′‐terpyridine, bipy = 2,2′‐bipyridine] has been synthesized and fully characterized, and compared with the previously reported [RuII(FT)(bipy)(NO)](PF6)3 complex [FT = 4′‐(9,9‐dihexyl‐9H‐fluoren‐2‐yl)‐2,2′:6′,2′′‐terpyridine]. Additionally, the X‐ray crystal structure of [RuII(CzT)(bipy)(NO2)](PF6), the precursor of [RuII(CzT)(bipy)(NO)](PF6)3, is reported. The presence of a tertiary amine in the carbazole unit leads to redshifted charge‐transfer transitions towards the electron‐withdrawing Ru–NO fragment and hence enhanced two‐photon absorption (TPA) properties. In contrast, the quantum yield of the NO· photorelease process is lower for the carbazole‐containing complex. The issue of optimization of the TPA versus NO·‐release capabilities is addressed. [ABSTRACT FROM AUTHOR]

Multifunctional core--shell nanocomposites are excellent platforms for effective drug delivery, and controlled release is attracting increasing attention from researchers owing to its advantages in cancer therapy. Here, a new nanocomposite containing nitrogen-doped carbon dots (N-CDs) embedded in ferromagnetic Fe3O4 cores and a pH-sensitive shell constituted by hydroxyapatite (HA) with loaded 5-fluorouracil (5-FU) was successfully synthesized. The nanocomposite can be used for near-infrared laser-induced photothermal cancer therapy and synergetic chemotherapy. The pH-sensitive HA shell exhibits a high drug-loading capability and achieves a pH-controlled and multistage drug release. As a result, this multifunctional core--shell N-CDs@Fe3O4@HA-5FU nanocomposite is an excellent and promising candidate with significant potential for targeted and synergetic cancer treatment. [ABSTRACT FROM AUTHOR]

This review is dedicated to a relatively new, but nevertheless very quickly evolving field of chemistry - closomer chemistry. Closomers are complex organoelement molecules built on a [B12]2- icosahedral platform that have the combined benefits of the symmetry and stability of polyhedral boranes and the diversity of organic chemistry. On a material level, closomers can be considered as monodisperse molecular nanoparticles because of their size, spherical symmetry, and ease of adjusting the arm length. The ease of twelvefold side-chain functionalization and the possibility of heterosubstitution makes closomers very useful medical tools for targeted and traceable imaging and drug delivery applications. [ABSTRACT FROM AUTHOR]

In this work, a new kind of multiple drug-release system, graphene oxide (GO)@polylactic acid (PLA)@hydroxyapatite (HA) composite microcapsule, was constructed through the double Pickering emulsion method. In the preparation of the microcapsules, GO and HA were used as stabilizers for the water-in-oil (W¹/O) and oil-in-water (O/W²) systems, respectively. Furthermore, GO, as the internal water phase (W¹), could carry a hydrophilic drug (5-FU), while PLA, as the oil phase (O), was employed to effectively embed a hydrophobic drug (coumarin). Additionally, the pH-sensitive HA in an external water phase (W²) could also act as a vector to carry hydrophilic rose bengal, due to its excellent adsorption ability. Dynamic optical experiment results show that the uniform size and complete structure of the GO@PLA@HA composite microcapsules can be obtained at a volume ratio of W¹/O/W² = 3:20:100. The pre-pared GO@PLA@HA composite microcapsules present good biocompatible, biodegradable, and pH-sensitive features. The respective drug encapsulation efficiencies of 5-FU, coumarin, and rose bengal are estimated to be 13.38 %, 48.58 %, and 53.24 %, and their loading efficiencies are 0.15 %, 4.49 %, and 5.3 %, respectively. The controlled release of drugs can be realized by the degradation of HA in the simulated acidic tumoral environment, which illustrates the pH-triggered drug-release behavior of HA. More importantly, the above three different drugs, with their hydrophilic or hydrophobic natures, could be loaded into the single W¹@O@W² microcapsule, and they exhibited multistage sustained release in PBS solution at pH 5.0. Thus, the as-synthesized composite microcapsules, with their multistage drug-delivery function, may act as a new and promising drug-delivery system in the medical field. [ABSTRACT FROM AUTHOR]

Self-assembled coordination cages are interesting as drug-delivery systems. Therefore, the synthesis of new M2L4 (M = Pd, Pt) molecular cages derived from highly fluorescent, rigid polyaromatic ligands is reported herein, and the first Pt2L4 cage with a ligand consisting of three pyridine moieties is described. The photophysical properties were examined, and they showed high quantum yields Φ of up to 48 % for the methoxy-functionalized ligands. Coordination of the ligands to palladium and platinum ions did, however, reduce the fluorescence of the metallocages. The host-guest chemistry of the palladium cages with cisplatin was investigated, which confirmed the encapsulation. The cages encapsulating cisplatin show significantly increased cytotoxicity towards A549 (human lung adenocarcinoma) cells relative to that shown by cisplatin and, thus, appear to be promising delivery vectors for the anticancer drug cisplatin. [ABSTRACT FROM AUTHOR]

Luminescent Ag nanoclusters (Ag-NC) provide the next generation in bionanoparticles, wherein the luminescence (650 nm) and large Stokes shift of these inorganic nanoclusters are favorable for biological imaging. By combining these characteristics with those of human serum albumin (HSA; a protein capable of binding multiple endo- and exogenous compounds), the Ag nanoclusters can be shielded from the environment and functionalized with (receptor) targeting moieties. Encapsulation of the 1.5 nm Ag nanoclusters by HSA resulted in a threefold increase in luminescence intensity and a twofold increase of the luminescence lifetime (1.7 vs. 3.6 µs). To exemplify the potential of this targeted concept, we functionalized HSA-Ag nanoparticles with chemokine receptor 4 (CXCR4) targeting peptides [Ac-TZ14011(CO2H)]. The resulting Ac-TZ14011-HSA-Ag nanoparticles demonstrated specific binding to CXCR4-overexpressing tumor cells. Upon exposure to (ambient) light, particle-functionalized tumor cells were killed. Combined, these experiments illustrate that HSA-Ag nanoparticles may have a potential in biological imaging and possibly even in targeted theranostic applications. [ABSTRACT FROM AUTHOR]

A new nanocarrier for loading and releasing drugs is reported, and ketoprofen was used as a model drug. More precisely, the carrier is a hybrid material prepared by combining oil-in-water (O/W) nanoemulsions, into which the drug has been solubilized, with mesostructured silica. This organic-inorganic hybrid material shows a controlled release of the drug that is pH dependent. If the drug is impregnated into the bare hierarchical meso-/macroporous dual silica material, obtained after the removal of the organic components by extraction, only 8 wt.-% of ketoprofen is released in a phosphate buffer medium (pH 7.4), probably owing to its low solubility in the aqueous phase. The drug solubility and release are increased strongly by the addition of Pluronic micelles to the receptor phase; this suggests a micelle-promoted and -assisted release mechanism. Whatever the vehicle, the release profiles of ketoprofen always follow the Korsmeyer-Peppas model with a diffusional release exponent value lower than 0.5, characteristic of a pseudo-Fickian release mechanism. Moreover, the release of ketoprofen is better controlled from the hybrid nanocarrier than from the hierarchical bare porous silica. [ABSTRACT FROM AUTHOR]

The interactions of MnII ions with the nonsteroidal anti-inflammatory drug sodium diclofenac in the presence of 1,10-phenanthroline and 2,2′-dipyridylamine lead to the formation of the trinuclear [Mn3(diclofenac)6(1,10-phenanthroline)2(MeOH)] ( 1) and the mononuclear [Mn(diclofenac)2(2,2′-dipyridylamine)] ( 2), respectively, which have been characterized by X-ray crystallography. Three different coordination modes of the diclofenac ligands exist in 1, whereas the bidentate chelating mode is observed in 2. In the initial evaluation of their biological properties and potential applications, the complexes exhibited good binding propensity to human or bovine serum albumin proteins and have relatively high binding constants. The ability of the compounds to scavenge 1,1-diphenylpicrylhydrazyl, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), and hydroxyl radicals was evaluated, and 1 was the most-effective scavenger among 1, 2, and sodium diclofenac. [ABSTRACT FROM AUTHOR]

We present the fabrication, upconversion-luminescence cell imaging, and drug-storage/release properties of upconversion-luminescent core/mesoporous-silica-shell-structured β-NaYF4:Yb3+,Er3+@SiO2@mSiO2 composite nanospheres with a size of 80 nm. The biocompatibility test on L929 fibroblast cells using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay reveals the low cytotoxicity of the system. The drug-storage and in vitro release tests indicate that these multifunctional nanomaterials have controlled drug-loading and -release properties for ibuprofen (IBU). Moreover, the upconversion (UC) emission intensity of IBU-β-NaYF4:Yb3+,Er3+@SiO2@mSiO2 composite nanospheres increases gradually along with the released amount of IBU. Additionally, upconversion luminescence images of β-NaYF4:Yb3+,Er3+@SiO2@mSiO2 uptaken by cells show clear green emission under 980 nm infrared laser excitation. These findings make these material promising for applications in the bioimaging, drug delivery, and disease therapy fields on the basis of its upconversion-luminescent and mesoporous properties. [ABSTRACT FROM AUTHOR]

Magnetic Fe3O4 nanoparticles (MNPs) have been covalently modified with β-cyclodextrin (β-CD) cavities by adopting a two-step anchoring route based on particle prefunctionalization with a phosphonic monolayer, which acts as a covalent linker between the MNPs and β-CD. Particular attention has been devoted to the study of the functionalization process by adopting bifunctional phosphonic linkers to investigate the efficiency of the anchoring group (phosphonic acid or ester) and the role of a second functional group. The grafting process of the phosphonic linkers has been monitored by using X-ray photoelectron and FTIR spectroscopy. β-CD has then been successfully anchored on MNPs prefunctionalized with (3-aminopropyl)phosphonic acid. The ability of β-CD-functionalized nanoparticles to carry and slowly release some drugs has been tested by adopting the anti-inflammatory drug diclofenac sodium salt as a model. [ABSTRACT FROM AUTHOR]

We have prepared organic-inorganic hybrid materials consisting of layered metal hydroxides and hydrogel polymers for potential use as a drug delivery system. The hybrid materials were synthesized by an electrophoretic method; anionic precursors, OH-/CO32-, and cationic metal Zn2+ were migrated into hydrogel by applying an electrical potential of 25 V for 20 min to form inorganic nanocrystals inside the hydrogel matrix. Hydrozincite [Zn5(OH)8(CO3)] nanoparticles, a kind of layered metal hydroxide, were determined to develop inside the hydrogel according to powder X-ray diffraction, FTIR, and X-ray absorption spectroscopy. Scanning electron microscopic images showed that the prepared hybrid materials have well-dispersed inorganic nanoparticles in the hydrogel matrix. In order to evaluate the potential of the thus prepared hybrid materials as a drug-delivery system, the well-known antioxidant ferulic acid was incorporated and their time-dependent release profile was obtained by HPLC. [ABSTRACT FROM AUTHOR]

A generalized in situ synthesis approach has been developed to prepare primary-amine-terminated mesoporous silica particles incorporated with a wide range of nanoparticles in the size range 2-50 nm, such as quantum dots, iron oxide nanoparticles, doped semiconductor nanocrystals, and gold nanorods. The resultant mesoporous particles are 50-800 nm in size and have a primary-amine-terminated surface and different morphology such as isolated spheres, rods, wires, or covalently connected aggregates. These mesoporous particles can be transformed into different functional nanoparticles for diverse applications such as drug delivery, bioimaging, and water purification. Quantum dot incorporated mesoporous particles have been demonstrated as multifunctional drug delivery carriers with simultaneous use as imaging probes. Similarly, quantum dot/gold nanorod incorporated mesoporous particles have been used as cellular imaging probes and their cellular interaction/uptake have been enhanced after functionalization with oleyl or TAT peptide. [ABSTRACT FROM AUTHOR]

The field of biomedical metallodendrimers is an emerging discipline that is attracting prolific attention. Metallodendrimers, like their organic counterparts, are known for their multivalency (high concentration of peripheral end-groups), well-defined architectures and narrow polydispersity. These are characteristics that make metallodendrimers well-suited as innovative scaffolds for the development of new therapeutic agents. Coupled with the surge of interest in the use of various metal complexes to treat various diseases, the application of metallodendrimers in medicinal chemistry is an attractive strategy for therapies involving macromolecules and the advancement of new metal-based therapeutics. In this review, we describe the progress made in the application of metallodendrimers as scaffolds for drug delivery, as metal-based drugs in their own right, and as agents for biosensing, photothermal and photodynamic therapy. [ABSTRACT FROM AUTHOR]