Violet Irradiation Research Articles

In situ gelling systems for drug delivery.

In situ gelling systems are polymeric formulations that are in sol forms before entering in the body, but change to gel forms under the physiological conditions. The sol-gel transition depends on one or a combination of different stimuli, like pH change, temperature modulation, solvent exchange, ultra violet irradiation and the presence of specific ions or molecules. Drug delivery systems having such properties can be widely used for sustained delivery vehicle preparation of the bioactive molecules. Some important advantages of these smart systems are ease of application and reduced frequency of administration, as well as protection of drug from environmental condition changes. Various natural and synthetic polymers undergo in situ gel forming and potentially can be used for oral, buccal, rectal, vaginal, ocular, intraperitoneal and parenteral drug delivery. Pectin, xyloglucan, gellan gum, chitosan and alginic acid are some of the natural polymers (1). The pectin gelation occurs in the presence of calcium ions. When pectin is administered orally, divalent cations induce gel formation in the stomach (2). Xyloglucan exhibits thermally reversible gelation with body temperature and have been used for oral, ocular, rectal and peritoneal drug delivery. An oral liquid in situ gelling system could successfully produce sustained release formulation and solve quick transit of liquid preparations from the gastrointestinal tract (1). Dilute aqueous solutions of alginates form firm gels, on addition of di and trivalent metal ions. The formation of covalent bonds, leading to the perception of the insoluble cross linked alginate hydrogels, reduces the release of embodied drugs in alginate matrices. A formulation containing sodium alginate and calcium ions, being added to sodium citrate delays gelation process until the administered solution reaches the acidic environment of the stomach. Additionally, buccal adhesive in situ gels have been formulated, using ion or pH sensitive polymers, to prolong the contact time of antifungal drugs in the oral cavity (1). Ophthalmic in situ gels have been developed to prolong precorneal contact time of ocular drugs. Sodium alginate and hydroxypropyl methyl cellulose have been used in the in situ gel formulation of diclofenac ophthalmic delivery (3). In situ gel formation of gellan gum occurs due to temperature modulations or the cations induced. Temperature and ionic condition (Ca2+) in tear fluid cause a transition of aqueous solution of gellan into the gel state (4). Carbopol (poly acrylic acid) is a well-known pH dependent polymer, which stays in solution form at acidic pH but forms a low viscosity gel at alkaline pH. An in situ gel was formulated for ocular delivery of ofloxacin, using carbopol and hydroxypropyl methylcellulose (HPMC). The latter was used to impart the viscosity to the carbopol solution, while reducing its acidity (5). On the other hand, an aqueous solution of carbopol-HPMC system was designed and developed for plasmid DNA delivery (6). Pluronic F-127 is a triblock copolymer with nonionic nature, which undergoes in situ gelation by temperature change. It was used together with Carbopol 934 and HPMC to prepare a vaginal in situ gel incorporating clotrimazole-β-cyclodextrin complex to ensure long residence time of drug at the application site (7). Chitosan aqueous solution forms a hydrated gel, like precipitate, at pH exceeding 6.2. Adding polyol salts, bearing a single anionic head, like glucose phosphate salts to chitosan aqueous solution can transform the cationic polysaccharides solution into thermally sensitive pH dependent gel. The sol form of such formulation (at the room temperature) turns into gel implants, when injected in vivo. This system was used successfully for tissue engineering applications (8). In situ gel formulations are of the most efficient treatment options, readily acceptable by physicians and patients. These systems offer successful controlled drug release and increase patient compliance.

Schiff base bridged biporphyrin: Synthesis, characterization and spectral properties

Chromophoric molecules with mono-aminophenyl, 5-aminophenyl-10, 15, 20-triphenyl porphyrin, were chemically reduced from the precursors of 5-nitrophenyl-10, 15, 20-triphenyl porphyrin. The titled Schiff base bridged biporphyrins were furthermore prepared by condensation of 5-aminophenyl-10, 15, 20-triphenyl porphyrin with terephthalaldehyde. This novel conjugated Schiff base biporphyrin was well characterized by spectral determinations. Experimental results indicated that the titled compound possessed fluorescence enhancement in near infrared region. Compared with tetraphenyl porphyrin, both ultraviolet–visible absorption and fluorescence spectra of the titled compound appeared with slightly red shift. Photo experiments revealed that, after violet irradiation, the color of a chloroform solution with the titled compound changed sharply from pale green to dark green along with sensitively spectral variation during ultraviolet–visible absorption and electron paramagnetic resonance determinations. This sensitively photochromic mechanism was well explained by molecular recognition of the titled compound towards hydrogen chloride from the decomposition of the chloroform solvent. The titled compound was sensitive in recognizing towards hydrogen chloride.

Aqueous degradation kinetics of pharmaceutical drug diclofenac by photocatalysis using nanostructured titania–zirconia composite catalyst

Diclofenac (DCF) is an anti-inflammatory pharmaceutical drug, and its presence in a trace amount in waste water makes severe environmental pollution. The degradation of DCF was investigated by a photocatalytic process in presence of ultra violet irradiation at room temperature using titania and titania-zirconia nanocom- posite catalysts in a batch reactor. The composite catalyst was prepared by sol-gel method and characterized by X-ray diffraction, transmission electron microscopy as well as BET surface area analyzer. The effect of various process parameters such as catalyst loading, initial concentration of DCF and pH of the experimental solution was observed on the degradation of DCF. The titania-zirconia nanocom- posites exhibited reasonably higher photocatalytic activity than that of anatase form of titania without zirconia. The maximum removal of DCF of about 92.41 % was achieved using Zr/Ti mass ratio of 11.8 wt% composite catalyst. A rate equation was proposed for the degradation of DCF using the composite catalyst. The values of rate constant (kc) and adsorption equilibrium constant (K1) were found to vary with the catalyst content in the reaction mixture.

Use of Hydroxyl Radical Yield to Investigate a Urea and Cobalt Modified TiO<sub>2</sub> Photocatalyst Degrading Rhodamine B under UV and Visible Light

Material modification of TiO2 photo-catalyst (NMTi) by doping urea and cobalt via sol-gel method was used to achieve high efficiency degradation of rhodamine B (RhB) under visible light (Vis). Although good removal (up to 42% of TOC removed) of RhB by Degussa P25 under ultra violet irradiation, P25 did not effectively degrade RhB (up to 14% TOC removed) under Vis. In the batch photo-catalytic experiment with Vis irradiation, the removal efficiencies of absorbance and TOC by NMTi were 28 and 30%. We used terephthalic acid as fluorescence probe to catch hydroxyl radical (OH) and calculated their quantum yields. The OH yields of NMTi with Vis irradiating was 8.91×10-6 while P25 of 2.65×10-6 (P25 of 1.44×10-5 and NMTi of 1.00×10-5 under UV). The OH yields of NMTi were higher than that of P25 under Vis, but otherwise under UV irradiation. Therefore, our new composited NMTi was more effective than P25 under Vis for both absorbance and TOC removal of RhB. It seemed possessed the application potential under Vis irradiation.

Kinetics of polarization gratings assisted with polarized violet light in bacteriorhodopsin films

Polarization gratings can be recorded in bacteriorhodopsin films by an orthogonal pair of linearly or circularly polarized beams. If a linearly polarized auxiliary violet light is added during the grating formation, the grating becomes polarization-sensitive. A theoretical model based on the two-state photochromic theory is proposed to calculate the diffraction efficiency kinetics of these polarization gratings. In both cases, the additional linearly polarized auxiliary violet irradiation improves the steady-state diffraction efficiency and leads to a cosine modulation of the steady-state diffraction efficiency by the polarization orientation of the readout beam. Experiment results demonstrate the correctness of the theoretical model.

TiO2-Bioactive Glass Nanostructure Composite Films Produced by a Sol-Gel Method: In Vitro Behavior and UV-Enhanced Bioactivity

The aim of this study is to develop TiO2, titania, -based composite films for 316 stainless steel substrate and to improve their apatite-forming activity. A series of sol-gel derived bioactive glass (49S) and bioactive glass (49S)-TiO2 films were deposited on the 316L stainless steel substrates by the spin-coating method. Amorphous bioactive glass (49S) film and polycrystalline titania-bioactive glass composite films were obtained after annealing the deposited layers at 600 °C. The microstructure and in vitro bioactivity of the composite films as well as the effect of titania nanopowder content and ultra violet (UV) irradiation on the in vitro bioactivity were investigated by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). While bioactivity tests are often carried out within 28-day periods, SEM and EDS data show that, after soaking in SBF for just 7 days, the prepared composite surfaces are covered with an apatite layer. The grown apatite layer consists of spherulites formed by nanosized needle-like aggregates. Fourier transform infrared spectroscopy investigations confirm apatite formation and suggest that the formed apatite is carbonated.

Structure and photocatalysis activity of silver doped titanium oxide nanotubes array for degradation of pollutants

Semiconductor titanium oxide showed a wonderful performance as a photocatalysis for environmental remediation. Owing to high stability and promising physicochemical properties, titanium oxide nanostructures are used in various applications such as wastewater treatment, antimicrobial and air purification. In the present study, titanium oxide nanotubes and silver doped titanium oxide nanotubes were synthesized via anodic oxidation method. The morphology and composition structure were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results depicted that nanotubes possess anatase phase with average tube diameter of 65nm and 230±12nm in length. The band gap of the un-doped and silver doped titanium dioxide nanotubes was determined using UV–Vis. spectrophotometer. The results showed that the band gap of titanium dioxide nanotubes is decreased when doped with silver ions. The photocatalysis activity of un-doped and silver doped TiO2 nanotubes were evaluated in terms of degradation of phenol in the presence of ultra violet irradiation. It was found that silver doped TiO2 nanotubes exhibited much higher photocatalysis activity than un-doped TiO2 nanotubes.

Homolytic Reactive Mass Spectrometry of Fullerenes: Peculiarities of the Reactions of C60 with Aromatic Compounds in the Ionization Chambers of Mass Spectrometers and in Solution

C60 reacted with PhH, PhCl, BnH, BnNH2, and o-C2H2B10H10 in the electron impact (EI) ion source of a mass spectrometer at 300 °C forming phenyl, benzyl, and o-carboranyl adducts, respectively, stabilized by hydrogen addition and loss. Besides, the additions to C60 of methyl and phenyl radicals for toluene, and a phenyl radical for benzylamine were observed. A homolytic reaction mechanism was suggested involving the reaction of the radicals formed from the aromatics under EI with C60 at the ionization chamber walls. While the ion/molecule reaction of C60 with benzene performed by Sun et al. under chemical ionization conditions at 200 °C afforded the complex C60•PhH(+•), quite a different isomer, HC60Ph(+•), was detected in the present study as a sequence of the different reaction mechanisms. C60 also reacted with benzyl bromide in the laser desorption/ionization (LDI) source of a mass spectrometer to give C60CPh(+). Phenyl and benzyl derivatives of C60 were found, respectively, when the reactions of the fullerene with PhCl, BnH, and BnBr were performed in solution under ultra violet irradiation. For the reaction with toluene, the strong chemically induced dynamic electron polarization of the intermediate benzylfullerenyl radical with the reverse phase effect was found. The coincidence of the results of the mass spectrometry and solution reactions of C60 with aromatics, even though incomplete, additionally supports the hypothesis, formulated earlier, that the former results can predict the latter ones to a significant extent and shows that this conclusion is valid for both EI and LDI initiated reactions in mass spectrometers.

H2 production through oxide irradiation: Comparison of gamma rays and vacuum ultraviolet excitation

The production of molecular hydrogen by gamma radiolysis and vacuum ultra violet photolysis of dried and hydrated nanoporous titania and zirconia nanoparticles has been studied. The nanoparticles were prepared as free standing films using a surface sol-gel process on cellulose. A significant hydrogen production was observed for both TiO2 and ZrO2 in vacuum ultra violet or gamma irradiation. This production could be optimized by controlling the amount of water and by introducing hydroxyl radical scavengers in the irradiated systems. The mechanism underlying hydrogen production seems qualitatively different in gamma and in vacuum ultra violet (VUV) irradiation.

NOVEL INSITU POLYMERIC DRUG DELIVERY SYSTEM: A REVIEW

In situ forming polymeric formulations are drug delivery systems that are in sol form before administration in the body, but once administered, undergo gelation in situ, to form a gel. The formation of gels depends on factors like temperature modulation, pH change, presence of ions and ultra violet irradiation, electrical sensitivity, enzyme sensitive from which the drug gets released in a sustained and controlled manner. Routes of administration are oral, ocular, rectal, vaginal, injectable and intraperitoneal. Various biodegradable polymers that are used for the formulation of in situ gels include gellan gum, alginic acid, xyloglucan, pectin, chitosan, poly (DL lactic acid), poly (DL-lactide-co-glycolide) and poly-caprolactone. The in situ gel forming polymeric formulations offer several advantages like sustained and prolonged action in comparison to conventional drug delivery systems and good patient compliance, good stability and biocompatibility characteristics make the in situ gel dosage forms very reliable. Evaluation of In situ gel systems include in vitro drug release studies, sol-gel transition temperature and gelling time, gel strength, viscosity & rheology, texture analysis, clarity. Commercial formulations of in situ polymeric systems are Regel Depot Technology, Cytoryn and Timoptic-Xe. Recent developments in the field of polymer science and technology has led to the development of various stimuli sensitive hydrogels like pH, temperature sensitive, which are used for the targeted delivery of proteins to colon, and chemotherapeutic agents to tumors. Sustained and prolonged release of the drug, good stability and biocompatibility characteristics make the in situ gel dosage forms very reliable. From a manufacturing point of view, the production of such devices is less complex and thus lowers the investment and manufacturing. Â KEYWORDS: Biodegradable polymers, polymeric gel, controlled release, in situ gels, poly (lactic-co-glycolic acid), sustained release.

In Situ Gel: A Novel Approach of Gastroretentive Drug Delivery

The oral delivery of drugs with a narrow absorption window in the gastrointestinal tract (GIT) is often limited by poor bioavailability with conventional dosage forms due to incomplete drug release and short residence time at the site of absorption. To overcome this drawback and to maximize the oral absorption of these drugs, novel drug delivery systems have been developed. Gastroretentive systems such as floating systems, mucoadhesive, high-density, expandable and have been developed, since they provide controlled delivery of drugs with prolonged gastric residence time. Among all oral dosage forms, liquid orals are more prone to low bioavailability as far as stomach specific drug deliveries are concerned, since they subjected to faster transit from the stomach/ duodenum. To produce sustained release formulation of an oral liquid formulation could be successfully augmented substantially through a strategy of liquid in-situ floating gel system. The formation of gel depends on factors like temperature modulation, pH change, presence of ions and ultra violet irradiation, from which the drug gets released in a sustained and controlled manner. This comprehensive article contains approaches, polymers, marketed preparations, patents, herbal approaches and recent advances of in situ gel.

Surface morphology effects on the light-controlled wettability of ZnO nanostructures

ZnO nanostructures of diverse morphology with shapes of corrals and cabbages as well as open and filled hexagons and sheaves prepared by APMOCVD technique, are investigated with water contact angle (CA) analysis. The as-grown ZnO nanostructures exhibit pure hydrophobic behavior, which is enhanced with the increase of the nanostructure's surface area. The most hydrophobic structures (CA=124°) were found to be the complex nanosheaf, containing both the macro-and nanoscale features. It is concluded that the nanoscale roughness contributes significantly to the hydrophobicity increase. The character of wettability was possible to switch from hydrophobic-to-superhydrophilic state upon ultra violet irradiation. Both the rate and amplitude of the contact angle depend on the characteristic size of nanostructure. The observed effect is explained due to the semiconductor properties of zinc oxide enhanced by increased surface chemistry effect in nanostructures.

1303 軽荷重接触磁気記録のHDIトライボロジーに関する研究 : UV照射の影響(GS-16 トライボロジー特性(2))

1303 軽荷重接触磁気記録のHDIトライボロジーに関する研究 : UV照射の影響(GS-16 トライボロジー特性(2))

Photocatalytic degradation of organic dyes under UV–Visible light using capped ZnS nanoparticles

Abstract Purification techniques like ozonization, chlorination and filtration have their own limitations of corresponding energy sources and harmful waste generation. However, heterogeneous photo catalysis is used for producing oxidative agent (hydroxyl radical) which has been used as an environmentally harmonious decontamination process. Such safe and low energy consumable photo catalytic system is required for purification of polluted water. Degradation of dyes is a standard method to check the photocatalytic activity of any type of photo catalyst. In this paper thioglycerol capped and uncapped ZnS nanoparticles are studied in detail for their photocatalytic activity and generation of electron hole pairs. Bromophenol blue, crystal violet and reactive red dyes were successfully photo reduced using ZnS nanoparticles after 3.0 h of irradiation. Since the photocatalytic activity depends on the generation of electron hole pairs and the existence of different phases, we have tried to correlate the optical and morphological studies with these results to understand the phenomenon of photocatalytic activity at nanoscale. Though the Ultra violet irradiation can efficiently degrade the dyes, naturally abundant solar radiation is also very effective in the mineralization of dyes. Hence, it may be a viable technique for the safe disposal of textile wastewater into the water streams.

Mycosporine and mycosporine-like amino acids: A paramount tool against ultra violet irradiation

Various facts demonstrated that UVB is harmful to organisms. Sunscreen compounds are usually used to prevent the excessive damage caused by UVB. However, certain photosynthetic organisms have evolved mechanisms to counteract the toxicity of ultraviolet radiation by synthesizing UV screening compounds such as mycosporine-like amino acids (MAAs). MAAs provide UV protection to primary and secondary consumers through food chain and to non-biological materials by photostabilizing action. Information related to the ecological consequence of MAAs and their spatial distribution from a wide range of organisms is accumulating. Hence, our studies seek a potent class of natural sun protective compounds to understand their relationship with environment and to develop a protocol for large-scale industrial production of these compounds so that they can find application as UV-protecting cosmetics.

Photoinduced and thermal oxidation of rapeseed and sunflower oils

The aim of the present study was to compare oxidative stability of different sunflower and rapeseed oils. Ultra violet (UV) irradiation was used as an accelerator of the oil oxidation process. After UV irradiation, the formed volatile compounds were extracted by headspace solid-phase microextraction HS-SPME (DVB/CAR/PDMS fibre) and analysed by gas chromatography coupled with a flame ionization detector (GC/FID). At the same time, the same oil samples were thermally oxidized. The induction periods were determined on the basis of hexanal to 2-trans-nonenal ratio in the analysed samples. Finally, the obtained results were compared with induction period values obtained through the determination of peroxide and anisidine values, and from the Rancimat method, manostatic test and differential scanning calorimetry (DSC) method. The results obtained using the new method were well correlated with those achieved with the well-established analytical techniques. The values of the induction period obtained after UV/HS-SPME/GC/FID were up to three times higher than those from Rancimat, but the correlation between these two methods was on a very good level (correlation coefficient R>0.98). Similar correlation was also observed between these new methods and the DSC or manostatic test. In all cases, better results were obtained for rapeseed oils than sunflower oils.

Evaluation of a new method for chemical coating of aluminum wire with molecularly imprinted polymer layer. Application for the fabrication of triazines selective solid-phase microextraction fiber

A new solid-phase microextraction (SPME) fiber is fabricated through ultra violet irradiation polymerization of ametryn-molecularly imprinted polymer on the surface of anodized–silylated aluminum wire. The prepared fiber is durable with very good chemical and thermal stability which can be coupled to GC and GC/MS. The effective parameters on the fabrication and application procedures such as spraying mode, ultra violet irradiation (polymerization) time, number of sprayings and polymerizations, pH and ionic strength of sample and extraction time were optimized. This fiber shows high selectivity with great extraction capacity toward triazines. SPME and GC analysis of ametryn, prometryn, terbutryn, atrazine, simazine, propazine and cyanazine using the fabricated fiber result in the detection limits of 9, 32, 27, 43, 51, 74 and 85 ng mL −1, respectively. The reliability of the prepared fiber in real samples has been investigated and proved by using spiked tap water, rice, maize and onion samples.

Treatment of methyl methacrylate from semiconductor wastewater by catalytic wet oxidation

Treatment of methyl methacrylate (MMA) from semiconductor wastewater via catalytic wet oxidation (CWAO) was studied. Effects of major operating parameters on the system performances in terms of the normalized concentrations of MMA and chemical oxygen demand (COD) relative to their initial values, namely C MMA/ C MMA0 and C COD/ C COD0, were investigated. These parameters include (1) the setting temperature T ST of operation, (2) the presence of catalyst Pt/Al 2O 3, (3) the presence of working gas, (4) the amount of Pt/Al 2O 3 ( m Pt) and (5) the partial pressure of O 2 ( p O 2 ). The change of pH value during the course of CWAO was also examined to elucidate the extents of decomposition of MMA and mineralization of COD. The results indicate that the effects of T ST on the C MMA/ C MMA0 are very vigorous for the case of sole wet oxidation (WAO) without catalyst. At the reaction time t FR = 180 min, the C MMA/ C MMA0 decreases from 0.89 at T ST = 180 °C to 0.62 at 200 °C and 0.09 at 220 °C with p O 2 = 2 MPa (based on the reference temperature T rf of 180 °C). The effects of T ST on the C COD/ C COD0 are not strong for the WAO, reducing the C COD/ C COD0 only to about 0.78–0.87 at t FR = 180 min with T ST in 160–220 °C. As for the CWAO in the presence of Pt/Al 2O 3 with m Pt = 30.38 g, the C MMA/ C MMA0 reduces greatly to 0.15 and 0.01–0.05 at t FR = 180 min with T ST at 160 °C and in 180–220 °C, respectively, while the C COD/ C COD0 decreases to about 0.16–0.34 with T ST in 160–220 °C. The use of Pt/Al 2O 3 not only improves the removal of MMA and COD but also reduces the T ST required for the efficient removal of MMA and COD, saving the energy needed. The results also reveal that the oxidizing gas such as O 2 is required for effective mineralization of COD via CWAO. However, the enhancement effect of increasing p O 2 is not significant if the supplied p O 2 is high enough, say 1–2 MPa, to proceed the CWAO in liquid phase with sufficient dissolved oxygen. Further, the CWAO is more efficient than the advanced oxidation processes of direct ultra violet irradiation (UV), sole ozonation (OZ) and combined process of OZ and UV for the effective removal of COD in the treatment of MMA. The information obtained in this study is useful for the proper operation and rational design of the CWAO system for the effective treatment of MMA-containing wastewater from the semiconductor industry.

107. RESPONSES OF THE PREIMPLANTATION EMBRYO TO DEFINED GENOTOXIC STRESSES

Genotoxic cellular stressors induce damage to the structure of DNA. This potentially compromises the genetic integrity of the cell. Such damage is particularly dangerous in the early embryo since transmission of defects can affect most cells in the body. Canonical responses of cells to such stress include delaying or blocking mitosis to allow DNA repair to occur or induction of cell death (apoptosis) to ensure that damage is not propagated. To date there have been only limited studies of the response of the preimplantation embryo to genotoxic stress. Ultra violet (UV) irradiation typically induces single strand DNA breaks while drugs such as the chemotherapeutic cisplatin commonly induce double strand breaks. ATM (Ataxia telangiectasia mutated) and ATR (Ataxia telangiectasia and rad3 related) are checkpoint kinase that mediate early responses of the cell to DNA damage. ATM primarily responds to DNA double strand breaks while ATR typically responds to single strand breaks and stalled replication forks. However, ATM and ATR may have partially overlapping and complementary functions. Both kinases can exert P53 dependent and independent responses. ATR protein was detected by immunofluorescence in all preimplantation stages up to the morulae stage. ATM protein was detected in oocytes and all stages. Cisplatin or UV-irradiation at the 2-cell stage caused increased nuclear staining of both ATM and ATR. UV-irradiation of 2-cell embryos induced irreversible, ATR-dependent, P53-independent cell-cycle block without apoptosis. Cisplatin allowed cell-cycle progression with progressive ATR and ATM-dependent, P53-independent apoptosis over subsequent cell-cycles. UV-irradiation of morula caused an ATR and ATM-dependent, P53-independent block of blastocyst formation while the block caused by cisplatin was ATR and ATM-dependent and at least partially P53-dependent. The results demonstrate complexity and maturation of the cellular responses of the embryo to defined genotoxic stressors and help to define the nature of embryopathy under these circumstances.

Vapor phase surface functionalization under ultra violet activation of parylene thin films grown by chemical vapor deposition

Various reactive gas phase treatments have been investigated as surface functionalization dry processes with the goal to improve the wettability of parylene C films, keeping good optical properties in the visible range. The films were grown on different substrates by chemical vapor deposition with thicknesses ranging from 300 to 1630 nm. The polymer surface was treated under ultra violet (UV) irradiation at 254 nm in reactive atmospheres including He, H 2O, H 2O 2, O 2 and ambient air. The UV/O 2 treatment is the most efficient since the water contact angle decreases from 100° to 6° while the transmittance is maintained at 90% in the visible wavelengths. Furthermore it exhibits long life stability. The functionalization mechanism is discussed in relation with previous reports.