Personal Sun Exposure and Serum 25‐hydroxy Vitamin D Concentrations

Solar ultraviolet‐B radiation (UVB) is essential for epidermal vitamin D production. We aimed to quantitate the relationship between personal solar UV exposure and serum 25hydroxy vitamin D (25[OH]D) concentration. Blood was collected for 25(OH)D analysis in 207 South Australian adults aged 27–61 years. At the time of blood collection, each participant completed a questionnaire, which included a calendar for recall of sun exposure in the preceding 16 weeks. We examined the association between solar UV exposure and serum 25(OH)D graphically from smoothed scatter plots, and modeled it using multiple linear regression, with age, sex and body mass index as covariates. Estimated erythemal solar UV exposure in the 6 weeks before blood collection best predicted serum 25(OH)D concentrations. Serum 25(OH)D rose with increasing personal solar UV exposure to a maximum of about 89 nmol L^?1 at an estimated mean weekly solar erythemal UV exposure of about 1230 mJ cm^?2. The maximum was the same after accounting for clothing coverage and was reached at an estimated whole body equivalent exposure to ambient UV of ca 700 mJ cm^?2. These results suggest that an average maximum serum 25(OH)D of ca 89 nmol L^?1 is achieved from sun exposure in a healthy Australian adult population.     

Hydrogen Peroxide Enhances the Antibacterial Effect of Methylene Blue‐based Photodynamic Therapy on Biofilm‐forming Bacteria

Recently, increased attention has been focused on endoscopic disinfection after outbreaks of drug‐resistant infections associated with gastrointestinal endoscopy. The aims of this study were to investigate the bactericidal efficacy of methylene blue (MB)‐based photodynamic therapy (PDT) on Pseudomonas aeruginosa (P. aeruginosa), which is the major cause of drug‐resistant postendoscopy outbreak, and to assess the synergistic effects of hydrogen peroxide addition to MB‐based PDT on biofilms. In planktonic state of P. aeruginosa, the maximum decrease was 3 log₁₀ and 5.5 log₁₀ at 20 and 30 J cm^?2, respectively, following MB‐based PDT. However, the maximum reduction of colony forming unit (CFU) was decreased by 2.5 log₁₀ and 3 log₁₀ irradiation on biofilms. The biofilm formation was significantly inhibited upon irradiation with MB‐based PDT. When the biofilm state of P. aeruginosa was treated with MB‐based PDT with hydrogen peroxide, the CFU was significantly decreased by 6 log₁₀ after 20 J cm^?2, by 7 log₁₀ after 30 J cm^?2 irradiation, suggesting significantly higher efficacy than MB‐based PDT alone. The implementation of the combination of hydrogen peroxide with MB‐based PDT through working channels might be appropriate for preventing early colonization and biofilm formation in the endoscope and postendoscopy outbreak.     

Preparation of a chemically amplified photosensitive polyimide based on norbornene‐end‐capped poly(amic acid ethoxymethylester)

A positive‐working chemically amplified photosensitive polyimide (PSPI) developable with basic aqueous solutions was obtained from poly(amic acid ethoxymethylester) (PAAE) as a polyimide precursor and diphenyliodonium 5‐hydroxynaphthalene‐1‐sulfonate (DINS) as a photoacid generator. The norbornene‐end‐capped PAAE based on 4,4′‐oxydiphthalic anhydride and 4,4′‐oxydianiline exhibited high transparency at 365 nm. The protection ratio of the ethoxymethyl groups was optimized to maximize the difference between the dissolution rates of the exposed and unexposed areas. The acid generated from DINS in the UV‐exposed region effectively deprotected the ethoxymethyl groups of PAAE by a chemical amplification mechanism. A 10‐μm‐thick film of the PSPI precursor system containing 16 wt % DINS exhibited a sensitivity (D^o) of 1100 mJ cm^?2 when developed with a 2.38 wt % aqueous tetramethyl ammonium hydroxide solution at room temperature. A fine, positive, 5‐μm line‐and‐space pattern was fabricated in a 15‐μm‐thick film with 1500 mJ cm^?2 of UV exposure. This resolution is excellent in comparison with those previously reported for chemically amplified PSPIs, and such a film can thus be used as a buffer coating in semiconductor packaging. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5520–5528, 2005     

Synthesis and characterization of novel photosensitive polyimide based on 5‐(2,5‐dioxotetrahydrofuryl)‐3‐methyl‐3‐cyclohexene‐1,2‐dicarboxylic anhydride

A negative type photosensitive polyimide with alicyclic moiety (NPI) was synthesized from 5‐(2,5‐dioxotetrahydrofuryl)‐3‐methyl‐3‐cyclohexene‐1,2‐dicarboxylic anhydride and 4,4‐diaminobenzophenone by one‐step polymerization in m‐cresol. Properties of the polyimides were characterized and a photo‐crosslinking mechanism was investigated using DEPT ¹³C‐NMR and FT‐IR spectroscopy. The negative polyimide showed good photosensitivity on exposure to UV light from a mercury xenon lamp. The polyimide showed remarkable solubility difference after photo‐ irradiation with an exposure dose of 500 mJ/cm². The resulting negative pattern of the photo‐cured NPI exhibited 10 μm resolution. Glass transition temperature of the photo‐crosslinked polyimide was about 307°C, which increased by 10°C compared to that of the polyimide before UV exposure. Transmittance of NPI after photo‐irradiation was about 87% at 500 nm. Copyright © 2004 John Wiley & Sons, Ltd.     

Three‐component,negative‐type,alkaline‐developable,thermally stable,and photosensitive polymer based on poly(2,6‐dihydroxy‐1,5‐naphthalene), a crosslinker,and a photoacid generator

A negative working and chemically amplified photosensitive polymer has been developed, which is based on poly(2,6‐dihydroxy‐1,5‐naphthalene) (PDHN), the crosslinker 4,4′‐methylenebis[2,6‐bis(hydroxymethyl)]phenol, and the photoacid generator (5‐propylsulfonyloxyimino‐5H‐thiophen‐2‐ylidene)‐(2‐methylphenyl)acetonitrile. PDHN, with a number‐average molecular weight of 25,000, was prepared by the oxidative coupling polymerization of 2,6‐dihydroxynaphthalene with di‐μ‐hydroxo‐bis[(N,N,N′,N′‐tetramethylethylenediamine)copper(II)] chloride in 2‐methoxyethanol at room temperature. The resulting PDHN showed a 5% weight loss temperature of 440 °C in nitrogen and a low dielectric constant of 2.82. The resist showed a sensitivity of 8.3 mJ cm^?2 and a contrast of 11 when it was exposed to 436‐nm light, followed by postexposure baking at 100 °C for 5 min and development with a 2.38 wt % aqueous tetramethylammonium hydroxide solution at 25 °C. A fine negative image featuring 10‐μm line‐and‐space patterns was obtained on a film 3 μm thick exposed to 10 mJ cm^?2 of ultraviolet light at 436 nm in the contact‐printed mode. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2235–2240, 2004     

Serum Levels of 25‐Hydroxy‐Vitamin D3 Among Sun‐protected Outdoor Workers in Israel

The objective of this study was to evaluate the effect of reduced sun exposure of outdoor workers on vitamin D status using different modalities of sun protection, for primary prevention of skin cancer. 25‐OH‐D3 measurements were performed in two successive winters, 8 (interim) and 20 months after initiation of the study, in three groups of male outdoor workers, enrolled in either a complete, partial or minimal sun protection program. Ambient solar UVB radiation was monitored simultaneously. No intragroup or intergroup differences were observed between the interim‐ and postintervention measurements of mean 25‐OH‐D3, which were close to 30 ng mL^?1. Significant risk factors for postintervention 25‐OH‐D3 levels >33.8 ng mL^?1 (a surrogate for reduced sun protection) were: previous sunburn episodes (OR 2.5; 95% CI 1.01–6.3; P = 0.05) and younger age (OR 0.92; 95 CI 0.86–0.98; P = 0.009). Outdoor workers of Western, compared with those of Eastern paternal origin had a borderline significant risk (OR 2.4; 95% CI 0.9–6.3; P = 0.07). A borderline significant effect (OR 2.9; 95% CI 0.97–10.1; P = 0.085) was also noted for those in the minimal intervention group. In conclusion, sun protection among outdoor workers following a successful intervention did not suppress mean winter 25‐OH‐D3.     

Photodynamic Inactivation of Planktonic Cultures and Biofilms of Candida albicans Mediated by Aluminum‐Chloride‐Phthalocyanine Entrapped in Nanoemulsions

New drug delivery systems, such as nanoemulsions (NE), have been developed to allow the use of hydrophobic drugs on the antimicrobial photodynamic therapy. This study evaluated the photodynamic potential of aluminum‐chloride‐phthalocyanine (ClAlPc) entrapped in cationic and anionic NE to inactivate Candida albicans planktonic cultures and biofilm compared with free ClAlPc. Fungal suspensions were treated with different delivery systems containing ClAlPc and light emitting diode. For planktonic suspensions, colonies were counted and cell metabolism was evaluated by XTT assay. Flow cytometry evaluated cell membrane damage. For biofilms, the metabolic activity was evaluated by XTT and ClAlPc distribution through biofilms was analyzed by confocal laser scanning microscopy (CLSM). Fungal viability was dependent on the delivery system, superficial charge and light dose. Free ClAlPc caused photokilling of the yeast when combined with 100 J cm^?2. Cationic NE‐ClAlPc reduced significantly both colony counts and cell metabolism (P < 0.05). In addition, cationic NE‐ClAlPc and free ClAlPc caused significant damage to the cell membrane (P < 0.05). For the biofilms, cationic NE‐ClAlPc reduced cell metabolism by 70%. Anionic NE‐ClAlPc did not present antifungal activity. CLSM showed different accumulation on biofilms between the delivery systems. Although NE system showed a lower activity for planktonic culture, cationic NE‐ClAlPc showed better results for Candida biofilms.     

A Simple Synthetic Method of a 1,3,5‐Triazine UV Absorbent CGL‐479 and Its Characterization

As a novel ultraviolet (UV) absorbent with excellent performance in UVA section (320 ~ 400 nm), 2‐{2‐hydroxy‐4‐[(octyloxycarbonyl)ethylideneoxy]phenyl}‐4,6‐Bis(4‐biphenylyl)‐1,3,5‐triazine (CGL‐479) was synthesized in a simple method with a total yield of 45.3% in four steps. Its outstanding UV absorption capability (λ_max = 326 nm, ε_max = 4.15 × 10⁴ L?mol^?1?cm^?1), high thermostability [T₅ (the temperature of losing 5% in weight) = 385 °C], and compatibility with polymer materials make it a potential substitute of the traditional UV absorbents.     

Synthesis of photosensitive and thermosetting poly(phenylene ether) based on poly[2,6‐di(3‐methyl‐2‐butenyl)phenol‐co‐2,6‐dimethyl‐phenol] and a photoacid generator

A chemically amplified photosensitive and thermosetting polymer based on poly[2,6‐di(3‐methyl‐2‐butenyl)phenol (15 mol %)‐co‐2,6‐dimethylphenol (85 mol %)] ( 3c ) and a photoacid generator [(5‐propylsulfonyloxyimino‐5H‐thiophen‐2‐ylidene)‐(2‐methylphenyl)acetonitrile] was developed. Poly[2,6‐bis(3‐methyl‐2‐butenyl)phenol]‐co‐2,6‐dimethylphenol)] ( 3 ) with high molecular weights (number‐average molecular weight ～ 24,000) was prepared by the oxidative coupling copolymerization of 2,6‐di(3‐methyl‐2‐butenyl)phenol with 2,6‐dimethylphenol in the presence of copper(I) chloride and pyridine as the catalyst under a stream of oxygen. The structures of 3 were characterized with IR, ¹H NMR, and ¹³C NMR spectroscopy. 3 was crosslinked by a thermal treatment at 300 °C for 1 h under N₂. The 5% weight loss temperatures and glass‐transition temperatures of the cured copolymers reached around 420 °C in nitrogen and 300 °C, respectively. The average refractive index of the cured copolymer ( 3c ) film was 1.5452, from which the dielectric constant at 1 MHz was estimated to be 2.6. The resist showed a sensitivity of 35 mJ cm^?2 and a contrast of 1.6 when it was exposed to 436‐nm light, postexposure‐baked at 145 °C for 5 min, and developed with toluene at 25 °C. A fine negative image featuring 8‐μm line‐and‐space patterns was obtained on a film exposed to 100 mJ cm^?2 with 436‐nm light in the contact‐printed mode. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 149–156, 2005     

Effectiveness of the Photoactive Dye Methylene Blue versus Caspofungin on the Candida parapsilosis Biofilm in vitro and ex vivo

This research studied the effectiveness of the photoactive compound methylene blue (MB) activated with red LED light (576–672 nm) compared to that of caspofungin (CAS) on 1 Candida albicans and 3 Candida parapsilosis strains. Results were evaluated in terms of SMIC₅₀ for CAS or in PDI (photodynamic inactivation)‐SMIC₅₀ for MB (minimal inhibitory concentration inhibiting sessile biofilm to 50% in comparison to the control without CAS or after irradiation in comparison to the control without MB). While all strains were susceptible to CAS in planktonic form, the SMIC₅₀ was determined to be >16 μg mL^?1 when CAS was added to a 24 h biofilm. However, PDI‐MIC_50s (1.67 mW cm^?2, fluence 15 J cm^?2) were 0.0075–0.03 mmol L^?1. For biofilm, PDI‐SMIC_50s were in the range from 0.7 to 1.35 mmol L^?1. MB concentration of 1 mmol L^?1 prevented a biofilm being formed ex vivo on mouse tongues after irradiation regardless of the application time, in contrast to CAS, which was only effective at a concentration of 16 μg mL^?1 when it was added at the beginning of biofilm formation. PDI seems to be a promising method for the prevention of microbial biofilms that do not respond significantly to conventional drugs.     

Protective Effect of Curcumin Against Acute Ultraviolet B Irradiation‐induced Photo‐damage

Ultraviolet B (UVB) irradiation is one of the most dangerous insults for skin and causes sunburn, erythema, photoaging and photocarcinogenesis. Curcumin (diferuloylmethane), a yellow spice derived from dried rhizomes of Curcuma longa, has been shown to possess significant anti‐inflammatory, antioxidant, anticarcinogenic, antimutagenic, anticoagulant and anti‐infective effects. However, the protective effects of curcumin against acute photo‐damage are poorly understood. In this study, we investigated the photoprotective effects of curcumin against UVB‐induced acute photo‐damage in hairless mice and immortalized human keratinocytes (HaCaT). Topical application of curcumin significantly inhibited acute UVB (540 mJ cm^?2, for 3 successive days)‐induced inflammatory cells, collagen accrementition derangement and lipid peroxidation, and effectively induced NF‐E2‐related factor 2 (Nrf2) nuclear accumulation in uncovered (Uncv) hairless mice skin. Treatment of HaCaT cells with curcumin significantly attenuated acute UVB (300 mJ cm^?2)‐induced lactate dehydrogenase release, intracellular reactive oxygen species production and DNA damage, activated the expression of the phase II detoxifying enzymes and promoted DNA repair activity. The photoprotective effect provided by curcumin was potential associated with modulation of Nrf2‐dependent antioxidant response. Our study suggested that curcumin is a potential agent for preventing and/or treating UV radiation‐induced acute inflammation and photoaging.     

Effects of Enhanced UV‐B Radiation on Biochemical Traits in Postharvest Flowers of Medicinal Chrysanthemum

This article reported UV‐B radiation effects on biochemical traits in postharvest flowers of chrysanthemum. The experiment included six levels of UV‐B radiation (UV0, 0 μW cm^?2; UV50, 50 μW cm^?2; UV200, 200 μW cm^?2; UV400, 400 μW cm^?2; UV600, 600 μW cm^?2 and UV800, 800 μW cm^?2). Enhanced UV‐B radiation significantly increased hydrogen peroxide content (except for UV50), but did not evidently affect malondialdehyde content in flowers. Chlorophyll b and total chlorophyll content were significantly increased by UV600 and UV800. UV400 and UV600 significantly increased anthocyanins, carotenoids and UV‐B absorbing compounds content, and the activities of phenylalanine ammonia lyase (PAL) and cinnamic acid‐4‐hydroxylase (C4H) over the control. 4‐coumarate CoA ligase (4CL) activity was significantly decreased by enhanced UV‐B radiation (except for UV50). The relationships between UV‐B radiation intensities and the activities of secondary metabolism enzymes were best described by a second‐order polynomial. The R² values for UV‐B radiation intensities and the activities of PAL, C4H and 4CL were 0.8361, 0.5437 and 0.8025, respectively. The results indicated that enhanced UV‐B radiation could promote secondary metabolism processes in postharvest flowers, which might be beneficial for the accumulation of medically active ingredients in medicinal plants. The optimal UV‐B radiation intensities in the study were between UV400‐UV600.     

Solvent‐Vapor‐Induced Reversible Single‐Crystal‐to‐Single‐Crystal Transformation of a Triphosphaazatriangulene‐Based Metal–Organic Framework

A triphosphaazatriangulene (H₃L) was synthesized through an intramolecular triple phospha‐Friedel–Crafts reaction. The H₃L triangulene contains three phosphinate groups and an extended π‐conjugated framework, which enables the stimuli‐responsive reversible transformation of [Cu(HL)(DMSO)?(MeOH)]_n, a 3D‐MOF that exhibits reversible sorption characteristics, into (H₃L?0.5 [Cu₂(OH)₄?6 H₂O] ?4 H₂O), a 1D‐columnar assembled proton‐conducting material. The hydrophilic nature of the latter resulted in a proton conductivity of 5.5×10^?3 S cm^?1 at 95 % relative humidity and 60 °C.     

2,2,2‐trifluoroacetophenone‐based D‐π‐A type photoinitiators for radical and cationic photopolymerizations under near‐UV and visible LEDs

Two D‐π‐A‐type 2,2,2‐trifluoroacetophenone derivatives, namely, 4′‐(4‐( N,N‐diphenyl)amino‐phenyl)‐phenyl‐2,2,2‐trifluoroacetophenone (PI‐Ben) and 4′‐(4‐(7‐(N,N‐diphenylamino)‐9,9‐dimethyl‐9H‐fluoren‐2‐yl)‐phenyl‐2,2,2‐trifluoroacetophenone (PI‐Flu), are developed as high‐performance photoinitiators combined with an amine or an iodonium salt for both the free‐radical polymerization of acrylates and the cationic polymerization of epoxides and vinyl ether upon exposure to near‐UV and visible light‐emitting diodes (LEDs; e.g., 365, 385, 405, and 450 nm). The photochemical mechanisms are investigated by UV‐Vis spectra, molecular‐orbital calculations, fluorescence, cyclic voltammetry, photolysis, and electron‐spin‐resonance spin‐trapping techniques. Compared with 2,2,2‐trifluoroacetophenone, both photoinitiators exhibit larger redshift of the absorption spectra and higher molar‐extinction coefficients. PI‐Ben and PI‐Flu themselves can produce free radicals to initiate the polymerization of acrylate without any added hydrogen donor. These novel D‐π‐A type trifluoroacetophenone‐based photoinitiating systems exhibit good efficiencies (acrylate conversion = 48%–66%; epoxide conversion = 85%–95%; LEDs at 365–450 nm exposure) even in low‐concentration initiators (0.5%, w/w) and very low curing light intensities (1–2 mW cm^?2). © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1945–1954     

A new type of eco‐friendly resist based on nonchemically amplified system

Novel water‐processable photopolymers were designed to be useful as environment‐friendly photolithographic materials. By copolymerization of 2‐(2‐diazo‐3‐oxo‐butyryloxy)ethyl methacrylate (DOBEMA), hydroxyethyl methacrylate (HEMA), methacryllic acid (MAA), and sodium 4‐vinylbenzenesulfonate (SVBS), two kinds of polymers, poly(DOBEMA‐co‐HEMA‐co‐SVBS) for negative‐tone resist and poly(DOBEMA‐co‐MAA) for positive‐tone resist, were synthesized and their photolithographic properties were investigated. The single component negative‐tone resist produced 0.8 μm line and space patterns using a mercury‐xenon lamp in a contact printing mode using pure water as casting and developing solvent at a exposure dose of 25 mJ cm^?2. On the other hand, the single component positive‐tone resist produced 0.8 μm line and space patterns at a much higher dose of 150 mJ cm^?2. Thus, the negative resist showed much improved sensitivity when compared with the positive resist and the reported nonchemically amplified resists. This sensitivity is comparable with those of typical chemically amplified resists. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7534–7542, 2008     

Photodynamic Inactivation of Bacterial and Yeast Biofilms With a Cationic Porphyrin

The efficiency of 5,10,15,20‐tetrakis(1‐methylpyridinium‐4‐yl)porphyrin tetra‐iodide (Tetra‐Py⁺‐Me) in the photodynamic inactivation of single‐species biofilms of Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans and mixed biofilms of S. aureus and C. albicans was evaluated. The effect on the extracellular matrix of P. aeruginosa was also assessed. Irradiation with white light up to an energy dose of 64.8 J cm^?2 in the presence of 20 μm of Tetra‐Py⁺‐Me caused significant inactivation in all single‐species biofilms (3–6 log reductions), although the susceptibility was attenuated in relation to planktonic cells. In mixed biofilms, the inactivation of S. aureus was as efficient as in single‐species biofilms but the susceptibility of C. albicans decreased. In P. aeruginosa biofilms, a reduction of 81% in the polysaccharide content of the matrix was observed after treatment with a 20 μm PS concentration and a total light dose of 64.8 J cm^?2. The results show that the Tetra‐Py⁺‐Me causes significant inactivation of the microorganisms, either in biofilms or in the planktonic form, and demonstrate that polysaccharides of the biofilm matrix may be a primary target of photodynamic damage.     

Masked Rhodamine Dyes of Five Principal Colors Revealed by Photolysis of a 2‐Diazo‐1‐Indanone Caging Group: Synthesis,Photophysics, and Light Microscopy Applications

Caged rhodamine dyes (Rhodamines NN) of five basic colors were synthesized and used as “hidden” markers in subdiffractional and conventional light microscopy. These masked fluorophores with a 2‐diazo‐1‐indanone group can be irreversibly photoactivated, either by irradiation with UV‐ or violet light (one‐photon process), or by exposure to intense red light (λ～750 nm; two‐photon mode). All dyes possess a very small 2‐diazoketone caging group incorporated into the 2‐diazo‐1‐indanone residue with a quaternary carbon atom (C‐3) and a spiro‐9H‐xanthene fragment. Initially they are non‐colored (pale yellow), non‐fluorescent, and absorb at λ=330–350 nm (molar extinction coefficient (ε)≈10⁴ M^?1 cm^?1) with a band edge that extends to about λ=440 nm. The absorption and emission bands of the uncaged derivatives are tunable over a wide range (λ=511–633 and 525–653 nm, respectively). The unmasked dyes are highly colored and fluorescent (ε= 3–8×10⁴ M^?1 cm^?1 and fluorescence quantum yields (?)=40–85 % in the unbound state and in methanol). By stepwise and orthogonal protection of carboxylic and sulfonic acid groups a highly water‐soluble caged red‐emitting dye with two sulfonic acid residues was prepared. Rhodamines NN were decorated with amino‐reactive N‐hydroxysuccinimidyl ester groups, applied in aqueous buffers, easily conjugated with proteins, and readily photoactivated (uncaged) with λ=375–420 nm light or intense red light (λ=775 nm). Protein conjugates with optimal degrees of labeling (3–6) were prepared and uncaged with λ=405 nm light in aqueous buffer solutions (?=20–38 %). The photochemical cleavage of the masking group generates only molecular nitrogen. Some 10–40 % of the non‐fluorescent (dark) byproducts are also formed. However, they have low absorbance and do not quench the fluorescence of the uncaged dyes. Photoactivation of the individual molecules of Rhodamines NN (e.g., due to reversible or irreversible transition to a “dark” non‐emitting state or photobleaching) provides multicolor images with subdiffractional optical resolution. The applicability of these novel caged fluorophores in super‐resolution optical microscopy is exemplified.     

Stable All‐Organic Radicals with Ambipolar Charge Transport

A series of neutral long‐lived purely organic radicals based on the stable [4‐(N‐carbazolyl)‐2,6‐dichlorophenyl]bis(2,4,6‐trichlorophenyl)methyl radical adduct (Cbz‐TTM) is reported herein. All compounds exhibit ambipolar charge‐transport properties under ambient conditions owing to their radical character. High electron and hole mobilities up to 10^?2 and 10^?3 cm² V^?1 s^?1, respectively, were achieved. Xerographic single‐layered photoreceptors were fabricated from the radicals studied herein, exhibiting good xerographic photosensitivity across the visible spectrum.     

Halogenated Phenazines that Potently Eradicate Biofilms,MRSA Persister Cells in Non‐Biofilm Cultures,and Mycobacterium tuberculosis

Conventional antibiotics are ineffective against non‐replicating bacteria (for example, bacteria within biofilms). We report a series of halogenated phenazines (HP), inspired by marine antibiotic 1 , that targets persistent bacteria. HP 14 demonstrated the most potent biofilm eradication activities to date against MRSA, MRSE, and VRE biofilms (MBEC=0.2–12.5 μM), as well as the effective killing of MRSA persister cells in non‐biofilm cultures. Frontline MRSA treatments, vancomycin and daptomycin, were unable to eradicate MRSA biofilms or non‐biofilm persisters alongside 14 . HP 13 displayed potent antibacterial activity against slow‐growing M. tuberculosis (MIC=3.13 μM), the leading cause of death by bacterial infection around the world. HP analogues effectively target persistent bacteria through a mechanism that is non‐toxic to mammalian cells and could have a significant impact on treatments for chronic bacterial infections.     

Halogenated Phenazines that Potently Eradicate Biofilms,MRSA Persister Cells in Non‐Biofilm Cultures,and Mycobacterium tuberculosis

Conventional antibiotics are ineffective against non‐replicating bacteria (for example, bacteria within biofilms). We report a series of halogenated phenazines (HP), inspired by marine antibiotic 1 , that targets persistent bacteria. HP 14 demonstrated the most potent biofilm eradication activities to date against MRSA, MRSE, and VRE biofilms (MBEC=0.2–12.5 μM), as well as the effective killing of MRSA persister cells in non‐biofilm cultures. Frontline MRSA treatments, vancomycin and daptomycin, were unable to eradicate MRSA biofilms or non‐biofilm persisters alongside 14 . HP 13 displayed potent antibacterial activity against slow‐growing M. tuberculosis (MIC=3.13 μM), the leading cause of death by bacterial infection around the world. HP analogues effectively target persistent bacteria through a mechanism that is non‐toxic to mammalian cells and could have a significant impact on treatments for chronic bacterial infections.