Nanoparticles For Photodegradation Research Articles

ZnO nanoparticles for photodegradation of humic acid in water.

Humic acid (HA) is the most important precursor of toxic disinfection byproducts upon chlorination. Removing HA from water body is therefore critical in drinking water acquisition. In this research, ZnO nanoparticles are employed for photocatalysis under UV light at neutral pH to remove HA from a water environment. Almost 100% degradation of HA was achieved using 0.3 g/L of ZnO in 180 min with UV-A and UV-C light. Under identical experimental conditions, total organic carbon (TOC) removals reach 67% and 21% with UV-A and UV-C light, respectively. A higher degree of mineralization of HA is achieved with UV-A light although the degradation of HA is slightly better with UV-C light. This indicates that ZnO/UV-A has relatively low selectivity to degrade different compounds, including various intermediates from HA degradation. The use of UV-A light is therefore recommended for ZnO as it possesses higher mineralization ability. Negligible TOC is observed on the ZnO surface after photocatalytic reactions. In contrast, the adsorption of HA in dark conditions reaches 42% in 180 min. This strongly indicates that the adsorption of HA plays an important role in the photocatalytic degradation of HA, but it is not the main process for HA removal.

Synthesis and Application of Fe-Doped TiO2 Nanoparticles for Photodegradation of 2,4-D from Aqueous Solution

2,4-Dichlorophenoxyacetic (2,4-D) is a toxic herbicide used to control weeds in agricultural sector. However, its residuals in soil and water are harmful for human and aquatic life. Therefore, the aim of this study was to evaluate the photocatalytic degradation of 2,4-D from aqueous solution using the Fe-doped TiO2 nanoparticles in the presence of UV and sunlight irradiation. The nanoparticles were synthesized via a mild hydrothermal process. The characteristics of the synthesized nanoparticles were determined using powder X-ray diffraction, Fourier transform infrared and scanning electron microscopy techniques. The effects of different parameters, including pH, nanoparticle dosage, initial 2,4-D concentration and dopant percentage on the degradation of 2,4-D, were investigated. The results demonstrated that the successfully doped nanoparticles had likely pseudo-spherical morphology. The optimum conditions for photocatalytic degradation of 2,4-D obtained at pH 7, nanoparticle dosage = 0.4 g/l, initial 2,4-D concentration = 10 mg/l, dopant percentage = 1.5% and contact time = 120 min. Under the optimal conditions, the photocatalytic degradation efficiencies of 2,4-D under UV and sunlight irradiation were 65 and 72%, respectively. In addition, the findings showed that 2,4-D degradation efficiency increased with increasing dosage of nanoparticles, while it decreased with increasing initial concentration of 2,4-D and initial pH. Therefore, the Fe-doped TiO2 nanoparticles could be used for the photodegradation of 2,4-D, and it is recommended for the degradation of other organic pollutants from aqueous media especially in tropical areas where a free energy source, i.e., sunlight, is available.

Semiconducting polypyrrole@TiO2 pure anatase nanoparticles for photodegradation of reactive red 120 azo dye

In the recent years, the development of new and efficient materials for photocatalytic processes has been of growing interest for applications in wastewater treatment. In this sense, TiCl4 stabilized with H2SO4 was precipitated with ammonium hydroxide in the presence of sodium dodecyl sulfate and calcined to obtain thermally stable TiO2 nanoparticles, which were subsequently coated with semiconducting polypyrrole (PPy) by chemical oxidation resulting in a composite of TiO2@PPy. TiO2 and TiO2@PPy composite were characterized by SEM, Raman, XRD, UV/Vis–NIR, FTIR and TGA. It was observed that TiO2 consisted of spherical nanoparticles with number-average particle diameter of 19.2 nm and polydispersity index in sizes of 1.2, whereas TiO2@PPy composite consisted of agglomerated spherical PPy nanoparticles of number-average diameter of 182.4 nm coating TiO2 nanoparticles. The calculated optical bandgap of TiO2 was 3.07 eV, and it was demonstrated by the Rietveld refinement method of the XRD spectrum and from the Raman analysis that synthesized TiO2 corresponds to highly pure rhombic anatase crystal structure. TiO2@PPy composite was tested in the photodegradation of the reactive red 120 azo dye in aqueous solutions under visible light irradiation. It was observed that photodegradation rate increased with decreasing the initial dye concentration and increasing the composite load. Almost 100% of dye removal was achieved after 45 min of reaction for 20 mg L−1 of initial dye concentration and 1.0 g L−1 of composite load.

Synthesis, characterization, and performance evaluation of pristine and cerium‐doped WO3 nanoparticles for photodegradation of methylene blue via solar irradiation

AbstractIn this study, an effective photodegrading properties of WO3 nanoparticles has been enhanced by doping with cerium. To achieve our goal pristine and Ce‐doped WO3 nanoparticles were prepared by a simple and cost effective co‐precipitation route. Characterization of all the specimens were conducted which showed that there were no noticeable structural changes. WO3 retained its monoclinic structure even after doping with (3%, 5%, 8%, 10%) cerium which was also confirmed with X‐ray diffraction (XRD) and Raman spectroscopy. In addition, XRD and Fourier transform infra‐red spectroscopy also confirm that no new phases were formed in doped specimens. XRD also depicts that minimum crystallite size is achieved at 3% cerium doping. Scanning electron microscope images show decrease in particle size initially at 3% cerium doping, that is, ~80 ± 2.5 nm. In contrast, further increase in doping percentage increases crystallite and particle sizes. Additionally, defect generation increased at lower doping percentage ~3%. In contrast, further increase in dopant (5%, 8%, 10%) caused defect annihilation process to dominate over defect generation. C/Co ratio and rate constant (KMB) values suggest that maximum degradation of methylene blue will occur at 3% cerium doping due to increase in crystalline defects. Ultraviolet visible Spectroscopy further validates C/Co ratio and degradation rate constant values by showing drastic decline in peak intensity at 3% cerium doping. Therefore, 3% cerium‐doped WO3 is more effective photocatalyst to degrade methylene blue in comparison to most of the previously used photocatalysts. The prepared cerium‐doped WO3 nanoparticles as a sun light driven photocatalyst, may be utilized for industrial wastewater purification.

Comparison of TiO2 nanowires and TiO2 nanoparticles for photodegradation of resorcinol as endocrine model

In this contribution, comparison of TiO2 nanowires (TiO2 NWs) and TiO2 nanoparticles (TiO2 NPs) for photodegradation of resorcinol as endocrine model was extensively carried out. The results indicated that X-ray diffraction (XRD) patterns of the TiO2 NWs exhibited brookite and anatase phases; whereas, the prepared TiO2 NPs is pure anatase phase. TEM images of TiO2 NWs exhibit clear nanowire structures with the 2 μm length and diameter of 50–100 nm, while the TiO2 NPs particle sizes are 5–10 nm. The prepared TiO2 NWs and TiO2 NPs were compared with commercial photocatalyst TiO2-P25 by the determination of their photocatalytic performances. The photocatalytic efficiencies of TiO2 NWs, TiO2 NPs, and TiO2 P25 are amounted to be 98.7%, 98.4%, and 83% within 3-h illumination. However, the photodegradation rates TiO2 NPs, TiO2 NWs, and TiO2-P25 are 12.24 × 10−7 mol L−1 min−1, 10.79 × 10−7 mol L−1 min−1, and 5.77 × 10−7 mol L−1 min−1, i.e., the photodegradation rates TiO2 NPs is slightly faster than TiO2 NWs, and they are significantly greater 2 times than that of commercial photocatalysts TiO2-P25. The apparent rate constant k (min−1) value of TiO2 NPs and TiO2 NWs is higher than that of commercial TiO2-P25 for 3.3 and 3.25 times, respectively. From the economic point of view, TiO2 NPs calcined at 400 °C are chosen to be the optimum for saving energy in the preparation step without loss of photocatalytic efficiency.

NIR Light-Degradable Antimony Nanoparticle-Based Drug-Delivery Nanosystem for Synergistic Chemo-Photothermal Therapy in Vitro.

A novel drug-delivery nanosystem based on near-infrared (NIR) light-degradable antimony nanoparticles (AMNP) have been developed for synergistic chemo-phototherapy in vitro. The monodispersed AMNP were synthesized by using a simple and cost-effective method. Positively charged doxorubicin hydrochloride (DOX) was loaded onto the negatively charged surface of AMNP via electrostatic interaction and finally modified by polyacrylic acid (PAA) to enhance biocompatibility. Under NIR (808 nm) laser irradiation of the AMNP-DOX-PAA nanosystem, not only was high photothermal conversion efficiency of AMNP achieved but also pH-dependent DOX release was enhanced due to laser-induced hyperthermia. As a consequence, almost all of the HeLa cells (around 97%) were killed because of the combined effects of chemotherapy and photothermal therapy. More interestingly, AMNP showed very fast (about 10 min) laser-induced degradation that may help to minimize long-term toxicity after therapy by using same-wavelength NIR laser irradiation (808 nm). Computational total energy calculations and molecular dynamics simulations based on density functional theory (DFT) suggest that the NIR laser irradiation induces a photothermally activated reaction on the surface of AMNP in water, which can lead to surface degradation via the formation of Sb-H bonds first and then Sb-OH bonds upon further increase of temperature. This work demonstrates a simple platform that has potential applications for synergistic and highly effective chemo-photothermal therapy based on photodegradable nanoparticles.

Facile Hydrothermal Synthesis of Cu and Al Oxide Nanoparticles for Photodegradation of Chlorpyrifos.

Copper oxide (Cu₂O) and aluminum oxide (Al₂O₃) nanoparticles were successfully fabricated through a facile hydrothermal route. The stating materials were the metal salts of copper, aluminum, de-ionized water and gallic acid, where gallic acid played the role of benign stabilizing agent in the synthesis process. Crystallite size of the nanoparticles determined using Williamson Hall analysis were found to be 24 and 26 nm for aluminum oxide and copper oxide respectively. The average size of nanoparticles determined by using Transmission Electron Microscopy was found to be nearly 27 nm and the results were in good agreement with X-ray diffraction study. Catalytic efficacy of the metal oxide nanoparticles was described by using chlorpyrifos as a role model pesticide and degradation rate was found in the sequence of R Cu₂O (7.25 × 10-2 hr-1) > Al₂O₃ NPs (4.28 × 10-2 hr-1). Greater photocatalytic activity of Cu₂O nanoparticles might be attributed to the electron scavenging effect of Cu₂O nanoparticles. On account of these properties, it may be a promising candidate for the development of cost effective treatment of pesticides.

Synthesis and Characterization Ag Nanoparticles Supported on Bi2WO6 Nanoplates for Enhanced Visible-Light-Driven Photocatalytic Degradation of Rhodamine B

Heterostructure Ag/Bi2WO6 nanocomposites with different weight contents of Ag nanoparticles for photodegradation of rhodamine B (RhB) were successfully synthesized by solution precipitate-deposition method using sodium borohydride (NaBH4) as a reducing agent. The results of X-ray diffraction (XRD) and transmission electron microscopy (TEM) certify the successful synthesis of cubic Ag nanoparticles supported on the surface of orthorhombic Bi2WO6 nanoplates. X-ray photoelectron spectroscopy (XPS) revealed the presence of metallic Ag species supported on Bi2WO6 nanoplates. The photocatalytic performance of heterostructure Ag/Bi2WO6 nanocomposites were investigated through the degradation of RhB under visible light irradiation. In this research, Ag/Bi2WO6 nanocomposites exhibited excellent chemical stability and recyclability under visible light irradiation. The 5 wt% Ag/Bi2WO6 showed the highest photodegradation of RhB due to the Ag nanoparticles acting as an electron trapper, to restrain the recombination of photo-induced electrons and holes, to improve the charge separation, and to enhance the photocatalytic performance of Bi2WO6.

Biosynthesis of NiO nanoparticles for photodegradation of free cyanide solutions under ultraviolet light

In this study, we used an environmentally friendly green method to synthesize NiO nanoparticles (NiO NPs) with an extract from Persea americana seeds for use as photocatalysts in the photodegradation of free cyanide (FCN). The characteristics of the NiO NPs were determined by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), ultraviolet–visible (UV–Vis) analysis, and Fourier transform infrared (FTIR) spectroscopy. The XRD results indicated a cubic-type structure with space group Fm3m, No. (225). Morphological analysis conducted using TEM showed that the NiO NPs had rhombohedral and spherical shapes with slight agglomeration. The particle size calculated based on the TEM results was 11 nm. EDS analysis confirmed the elemental constituents of the samples with Ni and O atoms. The phase purity and chemical bonds in NiO were confirmed using FTIR spectroscopy analysis. UV–Vis analysis indicated that the NiO NPs samples exhibited good optical properties with a well-defined peak at 338.9 nm. The energy band gap Eg obtained for NiO NPs based on the optical analyses was 3.75 eV. The NiO NPs performed well as a photocatalyst under UV light during the photodegradation of FCN, where the maximum photocatalytic oxidation efficiency was 84% after irradiation for 30 min. The FCN photodegradation mechanism was elucidated based on the photocatalytic oxidation of compounds by oxygen with semiconductors.

Hydrothermally grown CdS nanoparticles for photodegradation of anionic azo dyes under UV-visible light irradiation.

A CdS photocatalyst was synthesized successfully at low temperature via a catalyst-free hydrothermal technique which is simple, green and also easily controlled. The synthesized CdS photocatalyst showed hexagonal wurtzite structure with high crystallinity and excellent optical properties. The catalyst was used for degradation of two anionic azo dyes namely reactive red (RR141) and Congo red (CR) azo dyes. The catalyst showed very high efficiency of 99.8% and 99.0% toward photodegradation of RR141 and CR dye, respectively. The photodegradation reaction followed pseudo-first order kinetics. Chemical scavenger studies showed that direct photogenerated hole transfer from CdS to the azo dye was most likely the major pathway for photodegradation of the azo dye. The chemical structure of the CdS photocatalyst remained stable after photodegradation. The CdS photocatalyst retains its original efficiency even after the fifth cycle of reuse indicating the advantages of stability and reusability. The CdS nanostructures will be suitable for removal of highly toxic and hazardous organic materials in environmental protection.

Laser synthesized magnetically recyclable titanium ferrite nanoparticles for photodegradation of dyes

In this work, contaminated free titanium ferrite nanoparticles were successfully prepared through laser ablation approach in liquid media. The synthesized nanoparticles were characterized in terms of the structural, bonding nature, chemical composition using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and Energy-dispersive X-ray spectroscopy (EDX) techniques. The X-ray diffraction (XRD) pattern confirmed multiphase structure of titanium ferrite nanoparticles and revealed a vast difference between the laser ablated nanoparticles and its mother target. The XRD, FTIR and Raman measurements showed the formation of magnetic titanium ferrite nanoparticles as compared to bulk target. EDX spectrum also confirmed the formation of titanium ferrite nanoparticles. The photo catalytic activity performance of synthesized nanoparticles was tested to Rhodamine 6 G which was studied through time based absorption variations noted by ultra violet visible spectroscopy. The photo catalytic degradation efficiency of the sample retained nearly 80% of its initial value after two cycle of operation. These magnetic titanium ferrite nanoparticles exhibited good photocatalytic activities under UV light irradiation and can be recycled many times by magnetic separation without major loss of activity. Present studies indicate that titanium ferrite nanoparticles are a promising material for contaminated groundwater treatment and might open a new avenue in the designing of a cheaper and efficient large scale water purification plants.

Optical application of Er-doped ZnO nanoparticles for photodegradation of direct red - 31 dye

Nowadays, growing world increasing demands of synthetic organic dyes which are widely used in food, leather and textile industries. This paper reports the simple rapid synthesis of Er doped ZnO nanoparticles by simple combustion method. Herein, different concentrations of Er (2.0 at. wt%, 2.5 at. wt %, 3.0 at. wt%, 3.5 at. wt%) were used as dopants. The synthesized nanoparticles were characterized in term of structural, morphological, optical and kinetic properties. These detailed characterization study confirmed that the prepared nanoparticles are well crystalline. It was observed that different concentration of Er greatly influences morphology, band gap and photocatalytic activity on ZnO nanoparticles. The prepared Er doped samples were used as photocatalyst for photodegradation of direct red 31 (DR-31) dye. From the photocatalytic experiment it was observed that the degradation percentage increases with increasing Er concentration up to 2.5 at. wt% and thereafter photocatalytic degradation was decreased. Thus the optimum concentrations of prepared nanoparticles (2.5 at. wt%) are exhibiting almost complete degradation only in 60 min under UV irradiation. Kinetic studied revealed that all the samples follows first order rate constant.

(Al, Er) co-doped ZnO nanoparticles for photodegradation of rhodamine blue

Pure and co-doped (Al, Er) ZnO nanoparticles (NPs) have been synthesized by hydrothermal method using (Zn, Er and Al) nitrates. X-ray diffraction patterns reveal the formation of single phase of ZnO wurtzite-type structure. The crystallite size for pure ZnO is in the order of 26.5 nm which decreases up to the range 14.2–22.0 nm after (Al, Er) co-doping. SEM micrographs show that the specimen is composed of regular spherical particles in the nanoscale regime with homogeneous size distribution and high tendency to agglomeration. FTIR spectra exhibit absorption lines located at wavenumbers corresponding to vibration modes between the constituent atoms. Raman spectra recorded under excitation (λ exc = 632.8 nm) reveal peaks related to modes of transverse and longitudinal optical phonons of the wurtzite ZnO structure. The energy band gap E g of ZnO:(Al, Er) NPs ranges in 3.264–3.251 eV. The photocatalytic activity of pure and co-doped (Al, Er) ZnO NPs was evaluated by the photodegradation of rhodamine blue under an irradiation of wavelength 554 nm. It is found that a photodegradation rate above 90 % could be achieved for a period of time of 40 min for pure ZnO and 120 min for (Al, Er) co-doped ZnO. A photodegradation mechanism is proposed.

Synthesis of mesoporous TiO2–curcumin nanoparticles for photocatalytic degradation of methylene blue dye

Herein, we demonstrate a facile route for synthesis a new photocatalyst based on TiO2–curcumin nanoparticles for photodegradation of methylene blue dye under UV and visible light irradiation. The photocatalyst was prepared by sol–gel method using chitosan as biodegradable polymer. The crystalline and the nanostructure were characteristic X-ray diffraction [XRD], adsorption–desorption isotherm and high resolution transmission electron microscopy [HRTEM]. However, the optical features of the samples were investigated by a UV–visible spectrophotometer. It is obvious to notice the removal of the majority of methylene blue dye on a pure titania surface via adsorption mechanism owing to the high surface area and to the organized mesoporous nature of the solid sample. Incorporation of curcumin on titania surface changes the removal direction from adsorption to the photocatalytic pathway. Various photocatalytic experiments were performed to investigate the influence of initial dye concentration, weight of catalyst, stirring and light intensity on the photocatalytic degradation of methylene blue as primary pollutant model. Chemical oxygen demand [COD] test confirms the complete degradation of methylene blue dye. The exceptional photocatalytic reactivity of titania–curcumin nanoparticles is referred to reduction in band gap energy and to the facility of electron transfer from II* curcumin energy level to titania conduction band which increases the concentration of reactive oxygen superoxide radicals which in turn prevents the electron–hole recombination. The effect of various scavengers on the methylene blue dye degradation was investigated using ethanol, ascorbic acid and methyl viologen. The results have pointed out that O2− and HO. are considered the main active species in the degradation process. A plausible pathway and mechanism for the photocatalytic degradation of methylene blue by titania–curcumin nanoparticles were illustrated.

Microbial cellulose as a support for photocatalytic oxidation of toluene using TiO2 nanoparticles

ABSTRACTThe aim of this study was to investigate the feasibility of toluene degradation using impregnated microbial cellulose (MC) with titanium dioxide (TiO2) nanoparticles (MC/TiO2). The effects of the initial toluene concentration and ultraviolet (UV) source on the degradation efficiency of toluene have been evaluated. The experimental results showed that the rate of toluene degradation decreased with an increasing of the inlet toluene concentration. After 40 min reaction time, the decomposition rate (%) of toluene decreased from 72.3% to 36.02% for experiments conducted at 100 and 500 ppm, respectively. The degradation efficiency of toluene decreased with application of UVA source instead of UVC source. The toluene degradation efficiency (%) reached to 87.79% and 76.87% for UVC and UVA irradiation, respectively. At initial toluene concentration of 100 mg/L, toluene degradation efficiency for photocatalysis and photolysis processes were 70.2% and 10.65%, respectively; indicating that the photocatalytic degradation efficiency is significantly higher than that of photolytic degradation efficiency. Furthermore, photocatalytic degradation kinetics of toluene was studied and the rates of degradation were found to conform to pseudo‐second‐order kinetic. As shown in the present study, impregnation of TiO2 nanoparticles on MC/TiO2 significantly increases toluene removal for short exposure time. It can be concluded that the MC acted as a local toluene concentrator by adsorbing pollutants from the air stream, and thereby diffusing them to the TiO2 nanoparticles for photodegradation. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43051.

Gene Regulation by Intracellular Delivery and Photodegradation of Nanoparticles Containing Small Interfering RNA

Although the use of small interfering RNA (siRNA) is a promising technique for gene regulation, spatiotemporal control of the effects of siRNA must be achieved if the technique is to be safe and practical. Here, a method for spatiotemporal regulation of genes with nanoparticles containing siRNA is reported. The siRNA is encapsulated in photodegradable nanoparticles that are internalized to SKOV3-Luc cells, where the siRNA is released from the nanoparticles by UV irradiation for 30 s. The encapsulated siRNA only shows no gene-silencing effects, but release of the siRNA upon UV radiation leads to sequence-specific silencing of the luciferase gene in the cells. These results indicate that photodegradable siRNA-containing nanoparticles can be useful for time- and space-dependent regulation of gene expression in cells.

The optimum conditions for synthesis of Fe3O4/ZnO core/shell magnetic nanoparticles for photodegradation of phenol

The photocatalysis of phenol was studied using Fe3O4/ZnO core/shell magnetic nanoparticles (MNPs). The photocatalysts were synthesized by coating of ZnO onto the magnetite by precipitation method and characterized by XRD, SEM and FTIR measurements. Using the Taguchi method, this study analyzes the effect of parameters such as calcinations time, calcinations temperature and molar ratio of Fe3O4:ZnO on the photo activity of Fe3O4/ZnO MNPs. XRD and FTIR analysis confirm that coating process was done successfully. SEM images show that the average particle size of synthesized Fe3O4/ZnO nanoparticles was about 50 nm. The phenol removal efficiency of 88% can be achieved by using a photocatalyst which is synthesized through the optimum conditions: calcinations temperature of 550°C, calcinations time of 2 hours and molar ratio of 1:10 for Fe3O4:ZnO.

One step synthesis of Ag/Ag3PO4/BiPO4 double-heterostructured nanocomposites with enhanced visible-light photocatalytic activity and stability

Heterogeneous Ag/Ag3PO4/BiPO4 photocatalyst was synthesized by a one-step low temperature chemical bath method and exhibited better photocatalytic activity and better stability than those of individual Ag3PO4 or BiPO4 nanoparticles for photodegradation of organic compounds (Rhodamine B) in the absence of electron accepters under visible light (λ>420nm). The enhanced photocatalytic performance is mainly ascribed to the strong visible-light absorption originating from high efficient separations of photogenerated electron–hole pairs through Ag3PO4/BiPO4 and Ag/Ag3PO4 heterostructures.

Development of a spatiotemporal method to control molecular function by using silica-based photodegradable nanoparticles

To effectively and safely use molecules, it is important to be able to control the timing and site of molecule activation. We developed a spatiotemporal method to control molecular function by using silica-based photodegradable nanoparticles that can be prepared under mild conditions. The function of various molecules, such as rhodamine B, Nile blue A, propidium iodide (PI), and rhodamine 110, bis-(N-CBZ-l-arginine amide), dihydrochloride (BZAR), was restricted by wrapping in the network structure of the nanoparticle gel. The encapsulated molecule was released from the gel by the light stimulus and its function was restored. Hence, this technique is applicable to the functional control of various molecules. The PI-encapsulated nanoparticles were internalized by the cells after being conjugated with the cell membrane permeability peptide, octaarginine, and were localized to the cytoplasm. Short-term irradiation (20 s) induced PI release from the nanoparticles and the rapid movement (less than 2 min) of the released PI to the nucleus. These nanoparticles are thus useful tools for the spatiotemporal control of various molecular functions because they permit the quick and transient release of encapsulated molecules after short-term irradiation and can be prepared under mild conditions.

Delivery, stabilization, and spatiotemporal activation of cargo molecules in cells with positively charged nanoparticles

Positively charged photodegradable nanoparticles that simultaneously encapsulated various compounds including small and large molecules were prepared. The nanoparticles were internalized to the cell by endocytosis and were stable within the cells for at least 4 days. The encapsulated molecules were released into the cytosol using light stimuli.