Mid-IR Light-Activatable Full Spectrum LaB6 Plasmonic Photocatalyst

Photocatalysts as long-lasting, benign reagents for disinfection of bacteria in hospitals and public areas/facilities/transportation vehicles are strongly needed. A common limitation for all existing semiconductor photocatalysts is the requirement of activation by external UV-vis-near-infrared (NIR) light with wavelengths shorter than ≈1265 nm. None of the existing photocatalysts can function during nighttime in the absence of external light. Herein, an unprecedented LaB6 plasmonic photocatalyst is reported, which can absorb UV-vis-NIR light and mid-IR (3900 nm) light to split water and generate hydrogen and hydroxyl radicals for the decomposition of organic pollutants, as well as kill multidrug-resistant Escherichia coli bacteria. Mid-IR light (≈2-50 µm) is readily available from the natural environments via thermal radiation of warm/hot objects on the earth including human bodies, animals, furnances, hot/warm electrical devices, and buildings.

Combined Gadolinium and Boron Neutron Capture Therapies for Eradication of Head-and-Neck Tumor Using Gd10B6 Nanoparticles under MRI/CT Image Guidance

Eradication of head-and-neck (H&N) tumors is very difficult and challenging because of the characteristic feature of frequent recurrence and the difficulty in killing cancer stem cells. Neutron capture therapy (NCT) is emerging as a noninvasive potential modality for treatments of various types of tumors. Herein, we report that 98.5% 10B-enriched anti-EGFR-Gd10B6 nanoparticles can not only deliver large doses of 158 μg 10B/g tumor tissues as well as 56.8 μg 157Gd/g tumor tissues with a very high tumor-to-blood (T/B) 10B ratio of 4.18, but also exert very effective CT/MRI image-guided combined GdBNCT effects on killing cancer stem cells and eradication of recurrent head-and-neck (H&N) tumors. This leads to a long average half-lifespan of 81 days for H&N tumor-bearing mice, which is a record-making result, and surpasses the best result reported in the literature using combined radiotherapy and T cell-mediated immunotherapy (70 d).

Advances of medical nanorobots for future cancer treatments

Early detection and diagnosis of many cancers is very challenging. Late stage detection of a cancer always leads to high mortality rates. It is imperative to develop novel and more sensitive and effective diagnosis and therapeutic methods for cancer treatments. The development of new cancer treatments has become a crucial aspect of medical advancements. Nanobots, as one of the most promising applications of nanomedicines, are at the forefront of multidisciplinary research. With the progress of nanotechnology, nanobots enable the assembly and deployment of functional molecular/nanosized machines and are increasingly being utilized in cancer diagnosis and therapeutic treatment. In recent years, various practical applications of nanobots for cancer treatments have transitioned from theory to practice, from in vitro experiments to in vivo applications. In this paper, we review and analyze the recent advancements of nanobots in cancer treatments, with a particular emphasis on their key fundamental features and their applications in drug delivery, tumor sensing and diagnosis, targeted therapy, minimally invasive surgery, and other comprehensive treatments. At the same time, we discuss the challenges and the potential research opportunities for nanobots in revolutionizing cancer treatments. In the future, medical nanobots are expected to become more sophisticated and capable of performing multiple medical functions and tasks, ultimately becoming true nanosubmarines in the bloodstream.

A high-index facet gold 12 tip nanostar for an improved electrocatalytic alcohol oxidation reaction with superior CO tolerance

Direct alcohol fuel cells have a long and promising future, which will require the development of highly active electrocatalysts for alcohol electrooxidation reactions. To this end, high-index facet nanomaterial-based electrocatalysts provide significant promise for the successful oxidation of alcohols. However, the fabrication and exploration of high-index facet nanomaterials are seldom reported, especially in electrocatalytic applications. Herein, we successfully synthesized a high index facet {711} Au 12 tip nanostructure for the first time using a single-chain cationic TDPB surfactant. Electrooxidation results demonstrate that a {711} high-index facet Au 12 tip exhibited much higher electrocatalytic activity (∼10-fold higher) than the {111} low-index facet Au nanoparticles (Au NPs) without being poisoned by CO under identical conditions. Besides, Au 12 tip nanostructures offer appreciable stability and durability. The high electrocatalytic activity with excellent CO tolerance is due to the spontaneous adsorption of the negatively charged -OH on the high-index facet Au 12 tip nanostars, as evidenced by the isothermal titration calorimetry (ITC) analysis. Our findings suggest that high-index facet Au nanomaterials are ideal candidate electrode materials for the electrooxidation reaction of ethanol in fuel cells.

Copper (I) Chloride-Catalyzed Photoredox Synthesis of Multifunctionalized Compounds at Room Temperature and Their Antifungal Activities

A simple visible-light-induced CuCl-catalyzed synthesis was developed for highly functionalized carbon-centered compounds (α-alk/aryloxy-α-diaryl/alkylaryl-acetaldehydes/ketones) at room temperature using benzoquinone, alkyl/aryl alcohol, and alkyl/aryl terminal/internal alkynes. Late-stage functionalized compounds show good antifungal activities, especially against Candida krusei fungal strain, in in vitro experiments (the Broth microdilution method). Moreover, toxicity tests (zebrafish egg model experiments) indicated that these compounds had negligible cytotoxicity. The green chemistry metrics (E-factor value is 7.3) and eco-scale (eco-scale value is 58.8) evaluations show that the method is simple, mild, highly efficient, eco-friendly, and environmentally feasible.

Visible-Light-Induced Oxidative α-keto-Dichlorination of Arylalkynes by CuCl2 at Room Temperature

A visible light-induced oxidative α-keto-dichlorination of terminal and internal aryl alkynes was developed to form dichloroacetophenones (DCAPs) and dichlorophenyl-acetophenones (DCPAPs), respectively, by using CuCl₂ as a photoredox catalyst in the presence of air at room temperature (without using any exogenous photocatalyst). Here, photoexcited CuCl₂ underwent ligand-to-metal charge transfer to generate a Cl radical, which readily added to the alkynes to form DCAPs or DCPAPs in the presence of O₂ . This α-keto-dichlorination reaction is a green and mild protocol as it produced water as the only by-product. Moreover, the evaluation of green chemistry metrics indicated that the E-factor (mass of wastes/mass of products) of the current α-keto-chlorination method is around 10.1 times lower than that of a literature-reported photochemical method. The Eco Scale value (score 55, which on a scale of 0-100 indicates an acceptable synthesis) signifies that this process is simple, highly efficient, eco-friendly, and cost-effective.

Hotspots in action: near-infrared light mediated photoelectrochemical oxygen evolution on high index faceted plasmonic gold nanoarchitectures

Photo-induced electrochemical water splitting is a fascinating approach to overcome the present energy demands as well as environmental issues. To this end, near-infrared (NIR) photocatalysts stand out as promising candidates (where 53% of the solar light is NIR light) to solve the present energy crisis but the lack of NIR-activated photocatalysts has remained a great challenge for decades. Herein, for the first time, we report the synthesis of high-index faceted plasmonic Au nano-branched 12 tip nanostars, which can absorb the whole spectral region of electromagnetic radiation (UV-vis-NIR), for efficient water splitting. Moreover, the plasmonic hot spots on the Au 12 tip nanostars significantly promote the photoelectrochemical oxygen evolution reaction (OER) under NIR light (915 nm) with long-term stability. Remarkably, the Au 12 tip nanostars exhibit 250-fold enhancement of activity under 915 nm laser irradiation and 6.5-fold enhancement of activity under 532 nm laser irradiation, as compared to the Au NPs. Furthermore, the Finite-Difference Time-Domain (FDTD) study confirmed that the significant photoelectrochemical (PEC) enhancement in the NIR light region could be attributed to the hot-electron injection/plasmonic hot spot mechanism upon localized surface plasmonic resonance (LSPR) excitation. Overall, we anticipate that the present work would help to develop new NIR photoelectrocatalysts for meeting future energy demands.

Salt-mediated, plasmonic field-field/field-lattice coupling-enhanced NIR-II photodynamic therapy using core-gap-shell gold nanopeanuts

Plasmonic field-field coupling-induced enhancement of the optical properties of dye molecules in the nanogaps among metal nanoparticle clusters and thin films has attracted significant attention especially in disease-related theranostic applications. However, it is very challenging to synthesize plasmonic core-gap-shell nanostructures with a well-controlled nanogap, uniform shape, and distances to maximize the plasmonic field-field coupling between the core and the shell. Herein, we synthesized Au@gap@AuAg nanopeanut-shaped core-gap-shell nanostructures (Au NPN) and tuned their optical absorption from near-infrared region-I (NIR-I) to near-infrared region-II (NIR-II) by filling their nanogap with a high dielectric NaCl_(aq) aqueous solution, which led to a dramatic redshift in the plasmonic absorption band by 320 nm from 660 to 980 nm and a 12.6-fold increase (at 1064 nm) in the extinction coefficient in the NIR region (1000-1300 nm). Upon filling the nanogap with NaCl_(aq) aqueous solution, the Au NPN6.5(NaCl) (i.e., ∼6.5 nm nanogap)-mediated NIR-II photodynamic therapy effect was dramatically enhanced, resulting in a much longer average lifespan of >55 days for the mice bearing a murine colon tumor and treated with Au NPN6.5(NaCl) plus 1064 nm light irradiation compared to the mice treated with Au NPN6.5 + 1064 nm light irradiation (without nanogap filled with dielectric NaCl_(aq), 40 d) and the doxorubicin-treated group (23 d). This study demonstrates a simple but effective method to tune and maximize the plasmonic field-field coupling between the metal shell and metal core of core-gap-shell nanostructures, the plasmonic field-lattice interactions, and biomedical applications for the treatment of tumors. Overall, our work presents a new way to enhance/maximize the plasmonic field-field and field-lattice coupling, and thus the performance/sensitivities in nanogap-based bioimaging, sensing, and theranostic nanomaterials and devices.

Recent Progress in Red Blood Cells-Derived Particles as Novel Bioinspired Drug Delivery Systems: Challenges and Strategies for Clinical Translation

Red Blood Cells (RBCs)-derived particles are an emerging group of novel drug delivery systems. The natural attributes of RBCs make them potential candidates for use as a drug carrier or nanoparticle camouflaging material as they are innately biocompatible. RBCs have been studied for multiple decades in drug delivery applications but their evolution in the clinical arena are considerably slower. They have been garnering attention for the unique capability of conserving their membrane proteins post fabrication that help them to stay non-immunogenic in the biological environment prolonging their circulation time and improving therapeutic efficiency. In this review, we discuss about the synthesis, significance, and various biomedical applications of the above-mentioned classes of engineered RBCs. This article is focused on the current state of clinical translation and the analysis of the hindrances associated with the transition from lab to clinic applications.

Investigating a Boronate-Affinity-Guided Acylation Reaction for Labelling Native Antibodies

The excellent molecular recognition capabilities of monoclonal antibodies (mAbs) have opened up exciting opportunities for biotherapeutic discovery. Taking advantage of the full potential of this tool necessitates affinity ligands capable of conjugating directly with small molecules to a defined degree of biorthogonality, especially when modifying natural Abs. Herein, a bioorthogonal boronate-affinity-based Ab ligand featuring a 4-(dimethylamino)pyridine and an S-aryl thioester to label full-length Abs is reported. The photoactivatable linker in the acyl donor facilitated purification of azide-labelled Ab (N₃ -Ab) was quantitatively cleaved upon brief exposure to UV light while retaining the original Ab activity. Click reactions enabled the precise addition of biotin, a fluorophore, and a pharmacological agent to the purified N₃ -Abs. The resulting immunoconjugate showed selectivity against targeted cells. Bioorthogonal traceless design and reagentless purification allow this strategy to be a powerful tool to engineer native antibodies amenable to therapeutic intervention.

Multifunctional CuO/Cu2O Truncated Nanocubes as Trimodal Image-Guided Near-Infrared-III Photothermal Agents to Combat Multi-Drug-Resistant Lung Carcinoma

Despite the development of various therapeutic modalities to tackle cancer, multidrug resistance (MDR) and incomplete destruction of deep tissue-buried tumors remain as long-standing challenges responsible for tumor recurrence and low survival rates. In addition to the MDR and deep tissue photoactivation problems, most primary tumors metastasize to the lungs and lymph nodes to form secondary tumors. Therefore, it leaves a great challenge to develop theranostic approaches to combat both MDR and deep tissue photoactivation problems. Herein, we develop a versatile plasmonic CuO/Cu₂O truncated nanocube-based theranostic nanomedicine to act as a triple modal near-infrared fluorescence (NIRF) imaging agent in the biological window II (1000-1500 nm)/photoacoustic imaging (PAI)/T₁-weighted magnetic resonance (MR) imaging agents, sensitize the formation of singlet oxygen (¹O₂) to exert nanomaterial-mediated photodynamic therapeutic (NIR-II NmPDT), and absorb long NIR light (i.e., 1550 nm) in the biological window III (1500-1700 nm) to exert nanomaterial-mediated photothermal therapeutic (NIR-III NmPTT) effects for the effective destruction of multi-drug-resistant lung tumors. We found that H69AR lung cancer cells do not create drug resistance toward plasmonic CuO/Cu₂O TNCs-based nanomedicines.

Demetylation of the sex-determining region Y gene promoter and incidence of disorder of sex development in cloned dog males

Canine cloning is occasionally accompanied by abnormal sexual development. Some male donor cells produce cloned pups with female external genitalia and complete male gonadal dysgenesis, which is classified as an XY disorder of sex development (XY DSD). In this study, we examine the potential of 5-aza-2'-deoxycytidine (5-aza-dC), a DNA methyltransferase inhibitor, to reduce the phenotypic abnormality XY DSD in somatic cell nuclear transfer (SCNT)- derived pups. We used a 9-year-old normal male German Shepherd dog as a cell donor. Donor cells were treated with 10 nM 5-aza-dC for 4 days before being used for SCNT. At the same stage of cell development, significantly lower levels of DNA methylation of the sex-determining region Y (SRY) promoter was observed in the treated donor cells compared to that in the untreated cells (95.2% versus 53.3% on day 4 for the control and treated groups, respectively). No significant differences were observed in the control or treatment groups concerning fusion rate, pregnancy rate (30 days or entire period), the number of pups, or the incidence of XY DSD. However, more XY DSD dogs were observed in the control group (31.25%) than in the treatment group (14.29%). Hypermethylation of the SRY promoter was observed in the XY DSD cloned pups in both the treatment (84.8%) and control groups (91.1 ± 1.4%) compared to the methylation level in the phenotypically normal male pups of the treatment (23.2 ± 20.9%) and control groups (39.1 ± 20.1%). These results suggest that 5-aza-dC treatment of donor cells can reduce the methylation level of the SRY promoter in donor cells, and thus, 5-aza-dC is advantageous for reducing the incidence of XY DSD in canine cloning.

Gamma Ray Irradiation Enhances the Linkage of Cotton Fabrics Coated with ZnO Nanoparticles

In this work, we aim to study zinc oxide (ZnO)-based functional materials over cotton fabrics and their effects after gamma ray exposure of 9 kGy. We found that the binding of the nanoparticles with cotton fabrics can be enhanced after irradiation. This could be due to the oxygen deficiency or defects created in the interface between ZnO and cotton fabrics after irradiation. Near-edge X-ray absorption fine structure and X-ray photoelectron spectroscopy (XPS) were used to detect the oxygen inadequacies generated in the interior and at the surface of the ZnO nanoparticles after gamma ray exposure. XPS results showed that the binding energy of Zn shifts by 2 eV at 1.5 kGy and by 4 eV at 9 kGy. This huge shift of about 4 eV is completely different from other works due to the reaction that takes place on the interface between ZnO nanostructures and cotton fabrics after gamma ray irradiation. Overall, this work suggests that after gamma ray irradiation, there is an enhanced level of binding between the coated functional nanoparticles and cotton fabrics, which can be advantageous for the textile industries.

Photosensitized reactive chlorine species-mediated therapeutic destruction of drug-resistant bacteria using plasmonic core-shell Ag@AgCl nanocubes as an external nanomedicine

Due to the rapid growth of drug-resistant bacterial infections, there is an urgent need to develop innovative antimicrobial strategies to conquer the bacterial antibiotic resistance problems. Although a few nanomaterial-based antimicrobial strategies have been developed, the sensitized formation of cytotoxic reactive chlorine species (RCS), including chlorine gas and chlorine free radicals, by photo-activatable plasmonic nanoparticles for evading drug-resistant bacterial infections has not yet been reported. To address this challenge, herein, we report the synthesis of an unprecedented plasmonic core-shell Ag@AgCl nanocrystal through an in situ oxidation route for the photo-induced generation of highly cytotoxic RCS. We present the detailed in vitro and in vivo investigations of visible light activated Ag@AgCl nanostructure-mediated evasion of drug-resistant bacteria. In particular, the in vivo results demonstrate the complete reepithelialization of the methicillin-resistant Staphylococcus aureus (MRSA) infected wounds on skin upon phototherapeutic treatment mediated Ag@AgCl NCs. To the best of our knowledge, this is the first unique example of using Ag@AgCl NCs as an external nanomedicine for photo-induced generation of RCS to mediate effective killing of both Gram-positive and Gram-negative drug resistance bacteria and healing of the subcutaneous abscesses in an in vivo mouse model.

Cu2 O Nanocrystals-Catalyzed Photoredox Sonogashira Coupling of Terminal Alkynes and Arylhalides Enhanced by CO2

Herein the first visible-light-activated Sonogashira C-C coupling reaction at room temperature catalyzed by single-metal heterogeneous Cu₂ O truncated nanocubes (Cu₂ O TNCs) was developed. A wide variety of aryl halides and terminal alkynes worked well in this recyclable heterogeneous photochemical process to form the corresponding Sonogashira C-C coupling products in good yields. Mechanistic control studies indicated that CO₂ enhances the formation of light-absorbing heterogeneous surface-bound Cu^I -phenylacetylide (λ_max =472 nm), which further undergoes single-electron transfer with aryl iodides/bromides to enable Sonogashira C sp 2 -C_sp bond formation. In contrast to literature-reported bimetallic TiO₂ -containing nanoparticles as photocatalyst, this work avoided the need of cocatalysis by TiO₂ . Single-metal Cu^I in Cu₂ O TNCs was solely responsible for the observed C sp 2 -C_sp coupling reactions under CO₂ atmosphere.

Visible-light-driven copper-catalyzed aerobic oxidative cascade cyclization of N-tosylhydrazones and terminal alkynes: regioselective synthesis of 3-arylcoumarins

An intuitive visible-light-driven copper-catalyzed process can accomplish regioselective functionalized 3-arylcoumarins via oxidative annulation of simple N-tosylhydrazones with terminal alkynes under O₂ (1 atm.) at room temperature.

Copper catalyzed photoredox synthesis of α-keto esters, quinoxaline, and naphthoquinone: controlled oxidation of terminal alkynes to glyoxals

Controlled oxidation of the terminal C Created by potrace 1.16, written by Peter Selinger 2001-2019 ]]> C triple bond using O₂ (1 atm) as an oxidant and reagent.

Herein, we report a facile visible light induced copper catalyzed controlled oxidation of terminal C Created by potrace 1.16, written by Peter Selinger 2001-2019 ]]> C alkynes to α-keto esters and quinoxalines via formation of phenylglyoxals as stable intermediates, under mild conditions by using molecular O₂ as a sustainable oxidant. The current copper catalysed photoredox method is simple, highly functional group compatible with a broad range of electron rich and electron poor aromatic alkynes as well as aliphatic alcohols (1°, 2° and 3° alcohols), providing an efficient route for the preparation of α-keto esters (43 examples), quinoxaline and naphthoquinone with higher yields than those in the literature reported thermal processes. Furthermore, the synthetic utility of the products has been demonstrated in the synthesis of two biologically active molecules, an E. coli DHPS inhibitor and CFTR activator, using the current photoredox process. In addition, we applied this methodology to the one-pot synthesis of a heterocyclic compound (quinoxaline, an FLT3 inhibitor) by trapping the intermediate phenylglyoxal with O-phenylenediamine. The intermediate phenylglyoxal can also be isolated and further reacted with an internal alkyne to form naphthoquinone. This process can be readily scaled up to the gram scale.

Near-Infrared-Light-Activatable Nanomaterial-Mediated Phototheranostic Nanomedicines: An Emerging Paradigm for Cancer Treatment

Cancer is one of the most deadly diseases threatening the lives of humans. Although many treatment methods have been developed to tackle cancer, each modality of cancer treatment has its own limitations and drawbacks. The development of minimally invasive treatment modalities for cancers remains a great challenge. Near-infrared (NIR) light-activated nanomaterial-mediated phototherapies, including photothermal and photodynamic therapies, provide an alternative means for spatially and temporally controlled minimally invasive treatments of cancers. Nanomaterials can serve as nanocargoes for the delivery of chemo-drugs, diagnostic contrast reagents, and organic photosensitizers, and can be used to directly generate heat or reactive oxygen species for the treatment of tumors without the need for organic photosensitizers with NIR-light irradiation. Here, current progress in NIR-light-activated nanomaterial-mediated photothermal therapy and photodynamic therapy is summarized. Furthermore, the effects of size, shape, and surface functionalities of nanomaterials on intracellular uptake, macrophage clearance, biodistribution, cytotoxicities, and biomedical efficacies are discussed. The use of various types of nanomaterials, such as gold nanoparticles, carbon nanotubes, graphene, and many other inorganic nanostructures, in combination with diagnostic and therapeutic modalities for solid tumors, is briefly reviewed.

Roller-Induced Bundling of Long Silver Nanowire Networks for Strong Interfacial Adhesion, Highly Flexible, Transparent Conductive Electrodes

Silver nanowires (AgNWs) have been the most promising electrode materials for fabrication of flexible transparent touch panel, displays and many other electronics because of their excellent electrical properties, cost effectiveness, synthesis scalability, and suitability for mass production. Although a few literature reports have described the use of short Ag NWs in fabrication of randomly oriented Ag NW network-based electrode, their electrical conductivities are still far lower than that of Ag films. So far, no any literature report was able to provide any simple solution to fabrication of large-area and mass-manufactural ability to address the issues, such as, conductivity, transparency, electrical current withstand, bending stability, and interfacial adhesion. In the current work, we provide a simple solution to conquer the above-mentioned challenges, and report the development of long Ag NW bundle network electrodes on large area PET films that were coated, aligned, and bundled quickly and simply using a steel roller. Our developed AgNWs-bundle networks had superior performance in optoelectronic properties (sheet resistance 5.8 Ω sq⁻¹; optical transmittance 89% at 550 nm wavelength), electrical current withstand up to 500 mA, and bending stability over 5000 bending cycles, and strong interfacial adhesion.

Singlet oxygen-mediated selective C-H bond hydroperoxidation of ethereal hydrocarbons

Singlet O₂ is a key reactive oxygen species responsible for photodynamic therapy and is generally recognized to be chemically reactive towards C=C double bonds. Herein, we report the hydroperoxidation/lactonization of α-ethereal C-H bonds by singlet O₂ (¹Δ_g) under exceptionally mild conditions, i.e., room temperature and ambient pressure, with modest to high yields (38~90%) and excellent site selectivity. Singlet O₂ has been known for > 90 years, but was never reported to be able to react with weakly activated C-H bonds in saturated hydrocarbons. Theoretical calculations indicate that singlet O₂ directly inserts into the α-ethereal C-H bond in one step with conservation of steric configuration in products. The current discovery of chemical reaction of singlet oxygen with weakly activated solvent C-H bonds, in addition to physical relaxation pathway, provides an important clue to a 35-year-old unresolved mystery regarding huge variations of solvent dependent lifetime of singlet O₂.

Reductive Deamination by Benzyne for Deoxy Sugar Synthesis Through a Domino Reaction

Benzyne was developed as a reducing agent in the key step of converting amino sugars and ketoses into deoxy sugars, which occur widely in natural products. Many deoxy sugars exhibit antibiotic and anticancer activities, and furthermore, they play essential biological roles. By treatment with CS2 and then Ac2O, amino sugars and ketoses were converted into the corresponding 1,3-thiazolidine-2-thiones. In the key step, these intermediates were treated with 2-trimethylsilylphenyl triflate (2.0 equiv.) and CsF (3.0 equiv.) in MeCN at 25 °C to produce acyclic enol acetates in 60-63 % yields. Saponification of the enol acetates with NaOMe/MeOH followed by intramolecular cyclization afforded the target 2-deoxy sugars. The key step of the reductive deamination involved a domino 1,2-elimination/[3+2]-cycloaddition/retro [3+2]-ring-opening sequence. The generality of this new method was proven by the use of various substrates, including pentoses, hexoses, monosaccharides, disaccharides, aldoses, and ketoses.

A disposable breath sensing tube with on-tube single-nanowire sensor array for on-site detection of exhaled breath biomarkers

This paper presents a novel disposable breath-sensing tube with an on-tube single-nanowire (NW) sensor array for noninvasive, simple, and on-site detection of exhaled breath biomarkers. Although various noninvasive detection methods for lung cancer biomarkers in breath samples exist, they are unsuitable for self-diagnostics and immediate detection because they entail complicated handling procedures and are time intensive. In this study, we simulated, fabricated, and characterized disposable nanosensors by using single TiO₂ and Ag NWs in flexible plastic tubes. The proposed sensors simultaneously detect 2-propyl-1-pentanol (2-PP) lung cancer biomarkers and changes in the humidity, flow rate, and temperature of the flowing gas. The optimal dimension of the tubes was determined and verified through dynamic simulations and experiments. The current tube design decreases sensing variation and moisture interference by 43.28% and 78.77%, respectively, compared with previous designs. In the future, the proposed breath sensor, which has a response time of less than 10 s, can be used in a tube for simple and quick screening of lung cancer patients with the 2-PP concentration exceeding 100 ppb. The developed breath-sensing platform can be applied in noninvasive on-site disease screening.

Synthesis of Multibranched Gold Nanoechinus Using a Gemini Cationic Surfactant and Its Application for Surface Enhanced Raman Scattering

High-yield multibranched Au nanoechinus possessing lengthy and dense branched nanorods on the surface were synthesized using a seed-mediated surfactant-directed approach in the presence of gemini cationic surfactant N,N,N'N'-tetramethyl-N,N'-ditetradecylethane-1,2-diaminium bromide (C14C2C14Br2), HAuCl4, AgNO3, and ascorbic acid. C14C2C14Br2 surfactant provides a versatile template in designing the unique morphology of Au nanoechinus with the assistance of AgNO3. UV-vis spectroscopic analysis proves that Au nanoechinus possess a unique intense broad localized surface plasmon resonance (LSPR) peak, which extends from 400 to 1700 nm in the NIR region making a highly potential platform for biomedical applications. Systematic time-dependent TEM, UV-vis-NIR, and XRD analysis were performed to monitor the morphological evolution of multibranched Au nanoechinus. It was found that the surface of branched nanorods of Au NE preferentially grew along (111) crystal planes. Furthermore, as-synthesized Au nanoechinus shows excellent SERS enhancement ability for dopamine inside HeLa cells.

Synthesis and Structure-Activity Relationships of Imidazole-Coumarin Conjugates against Hepatitis C Virus

A series of new conjugated compounds with a -SCH₂- linkage were synthesized by chemical methods from imidazole and coumarin derivatives. The experimental results indicate that of the twenty newly synthesized imidazole-coumarin conjugates, three of them exhibited appealing EC50 values (5.1-8.4 μM) and selective indices >20 against hepatitis C virus. Their potency and selectivity were increased substantially by modification of their structure with two factors: imidazole nucleus with a hydrogen atom at the N(1) position and coumarin nucleus with a substituent, such as Cl, F, Br, Me, and OMe. These guidelines provide valuable information for further development of conjugated compounds as anti-viral agents.

Copper(i)-catalysed oxidative C–N coupling of 2-aminopyridine with terminal alkynes featuring a CC bond cleavage promoted by visible light

An efficient and eco-friendly approach to aerobic oxidative C–N coupling of 2-aminopyridine with terminal alkynes for preparation of biologically important pyridyl-amides via CC triple bond cleavage at room temperature.

Copper(i) chloride catalysed room temperature Csp–Csp homocoupling of terminal alkynes mediated by visible light

An eco-friendly approach to the C_sp–C_sp homocoupling of terminal alkynes (including electron-withdrawing groups) was achieved at room temperature via a copper(i) chloride catalysed process mediated by visible light.

Preparation, cytotoxicity and in vivo bioimaging of highly luminescent water-soluble silicon quantum dots

Designing various inorganic nanomaterials that are cost effective, water soluble, optically photostable, highly fluorescent and biocompatible for bioimaging applications is a challenging task. Similar to semiconducting quantum dots (QDs), silicon QDs are another alternative and are highly fluorescent, but non-water soluble. Several surface modification strategies were adopted to make them water soluble. However, the photoluminescence of Si QDs was seriously quenched in the aqueous environment. In this report, highly luminescent, water-dispersible, blue- and green-emitting Si QDs were prepared with good photostability. In vitro studies in monocytes reveal that Si QDs exhibit good biocompatibility and excellent distribution throughout the cytoplasm region, along with the significant fraction translocated into the nucleus. The in vivo zebrafish studies also reveal that Si QDs can be evenly distributed in the yolk-sac region. Overall, our results demonstrate the applicability of water-soluble and highly fluorescent Si QDs as excellent in vitro and in vivo bioimaging probes.

Benzouracil-coumarin-arene conjugates as inhibiting agents for chikungunya virus

Chikungunya virus (CHIKV) is an arbovirus that was first recognized in an epidemic form in East Africa in 1952-1953. The virus is primarily transmitted through mosquitoes and the resulting disease, chikungunya fever, is found in nearly 40 countries. Neither an effective vaccine nor a specific antiviral drug exists for treatments of chikungunya fever. Thus 22 new conjugated compounds of uracil-coumarin-arene were designed and synthesized as potential inhibiting agents. Their chemical structures were determined unambiguously by spectroscopic methods, including single-crystal X-ray diffraction crystallography. The three units in these conjugates were connected by specially designed -SCH2- and -OSO2- joints. Five of these new conjugates were found to inhibit CHIKV in Vero cells with significant potency (EC50 = 10.2-19.1 μM) and showed low toxicity (CC50 = 75.2-178 μM). The selective index values were 8.8-11.5 for three conjugates. By analysis of the data from the anti-viral assays, the structure-activity relationship is derived on the basis of the nature of the uracil, the functional groups attached to the arene, and the joints between the ring units.

Designing multi-branched gold nanoechinus for NIR light activated dual modal photodynamic and photothermal therapy in the second biological window

Gold nanoechinus can sensitize the formation of singlet oxygen in the first and the second near-infra red (NIR) biological windows and exert in vivo dual modal photodynamic and photothermal therapeutic effects (PDT and PTT) to destruct the tumors completely. This is the first literature example of the destruction of tumors in NIR window II induced by dual modal nanomaterial-mediated photodynamic and photothermal therapy (NmPDT & NmPTT).

Fabrication of antibody microarrays by light-induced covalent and oriented immobilization

Antibody microarrays have important applications for the sensitive detection of biologically important target molecules and as biosensors for clinical applications. Microarrays produced by oriented immobilization of antibodies generally have higher antigen-binding capacities than those in which antibodies are immobilized with random orientations. Here, we present a UV photo-cross-linking approach that utilizes boronic acid to achieve oriented immobilization of an antibody on a surface while retaining the antigen-binding activity of the immobilized antibody. A photoactive boronic acid probe was designed and synthesized in which boronic acid provided good affinity and specificity for the recognition of glycan chains on the Fc region of the antibody, enabling covalent tethering to the antibody upon exposure to UV light. Once irradiated with optimal UV exposure (16 mW/cm(2)), significant antibody immobilization on a boronic acid-presenting surface with maximal antigen detection sensitivity in a single step was achieved, thus obviating the necessity of prior antibody modifications. The developed approach is highly modular, as demonstrated by its implementation in sensitive sandwich immunoassays for the protein analytes Ricinus communis agglutinin 120, human prostate-specific antigen, and interleukin-6 with limits of detection of 7.4, 29, and 16 pM, respectively. Furthermore, the present system enabled the detection of multiple analytes in samples without any noticeable cross-reactivities. Antibody coupling via the use of boronic acid and UV light represents a practical, oriented immobilization method with significant implications for the construction of a large array of immunosensors for diagnostic applications.

A general strategy to achieve ultra-high gene transfection efficiency using lipid-nanoparticle composites

Gene therapy provides a new hope for previously "incurable" diseases. Low gene transfection efficiency, however, is the bottle-neck to the success of gene therapy. It is very challenging to develop non-viral nanocarriers to achieve ultra-high gene transfection efficiencies. Herein, we report a novel design of "tight binding-but-detachable" lipid-nanoparticle composite to achieve ultrahigh gene transfection efficiencies of 60∼82%, approaching the best value (∼90%) obtained using viral vectors. We show that Fe@CNPs nanoparticles coated with LP-2000 lipid molecules can be used as gene carriers to achieve ultra-high (60-80%) gene transfection efficiencies in HeLa, U-87MG, and TRAMP-C1 cells. In contrast, Fe@CNPs having surface-covalently bound N,N,N-trimethyl-N-2-methacryloxyethyl ammonium chloride (TMAEA) oligomers can only achieve low (23-28%) gene transfection efficiencies. Similarly ultrahigh gene transfection/expression was also observed in zebrafish model using lipid-coated Fe@CNPs as gene carriers. Evidences for tight binding and detachability of DNA from lipid-nanoparticle nanocarriers will be presented.

First demonstration of gold nanorods-mediated photodynamic therapeutic destruction of tumors via near infra-red light activation

Previously, a large volume of papers reports that gold nanorods (Au NRs) are able to effectively kill cancer cells upon high laser doses (usually 808 nm, 1-48 W/cm²) irradiation, leading to hyperthermia-induced destruction of cancer cells, i.e, photothermal therapy (PTT) effects. Combination of Au NRs-mediated PTT and organic photosensitizers-mediated photodynamic therapy (PDT) were also reported to achieve synergistic PTT and PDT effects on killing cancer cells. Herein, we demonstrate for the first time that Au NRs alone can sensitize formation of singlet oxygen (¹O₂) and exert dramatic PDT effects on complete destrcution of tumors in mice under very low LED/laser doses of single photon NIR (915 nm, <130 mW/cm²) light excitation. By changing the NIR light excitation wavelengths, Au NRs-mediated phototherapeutic effects can be switched from PDT to PTT or combination of both. Both PDT and PTT effects were confirmed by measurements of reactive oxygen species (ROS) and heat shock protein (HSP 70), singlet oxygen sensor green (SOSG) sensing, and sodium azide quenching in cellular experiments. In vivo mice experiments further show that the PDT effect via irradiation of Au NRs by 915 nm can destruct the B16F0 melanoma tumor in mice far more effectively than doxorubicin (a clinically used anti-cancer drug) as well as the PTT effect (via irradiation of Au NRs by 780 nm light). In addition, we show that Au NRs can emit single photon-induced fluorescence to illustrate their in vivo locations/distribution.

Effects of surface functionality of carbon nanomaterials on short-term cytotoxicity and embryonic development in zebrafish

Cationic surface functionalities of nanomaterials, such as imidazolium and trimethylammonium ethyl methacrylate, induce strong cytotoxicity in vitro and in zebrafish.