Hydroquinone cream-based polymer microneedle roller for the combined treatment of large-area chloasma.

Melasma is a common hyperpigmented skin condition that occurs on the face and other areas prone to light exposure, seriously affecting people's quality of life. Microneedle, a new type of transdermal drug delivery device, can significantly improve skin permeability. In this study, we designed and fabricated a polymer microneedle roller (PMR) using a mold hot pressing method, and established a mouse model of melasma induced by ultraviolet radiation. The dynamometer and insertion test of MNs into parafilm and skin of mice indicates that the MNs have sufficient mechanical properties to insert parafilm and skin of mice. The two methods (apply hydroquinone cream (HQC) directly and pre-treat with PMR before applying HQC) were used to treat melasma. From the results of skin surface observation, determination of superoxide dismutase (SOD) activity and malondialdehyde (MDA) content in skin and liver tissues, histological observation, and skin Optical coherence tomography (OCT), we confirmed both the two methods had a therapeutic effect while the PMR pretreatment group exhibited a better therapeutic effect. In addition, there were statistical differences between the UV group (P < 0.05). Together these results indicated that the MNs may be promising in future clinical applications in improving the UV irradiation-induced pigmentation like melisma.

Transfer Printing of Perovskite Whispering Gallery Mode Laser Cavities by Thermal Release Tape.

The outstanding optoelectrical properties and high-quality factor of whispering gallery mode perovskite nanocavities make it attractive for applications in small lasers. However, efforts to make lasers with better performance have been hampered by the lack of efficient methods for the synthesis and transfer of perovskite nanocavities on desired substrate at quality required for applications. Here, we report transfer printing of perovskite nanocavities grown by chemical vapor deposition from mica substrate onto SiO2 substrate. Transferred perovskite nanocavity has an RMS roughness of ~ 1.2 nm and no thermal degradation in thermal release process. We further use femtosecond laser to excite a transferred perovskite nanocavity and measures its quality factor as high as 2580 and a lasing threshold of 27.89 µJ/cm2 which is almost unchanged as compared with pristine perovskite nanocavities. This method represents a significant step toward the realization of perovskite nanolasers with smaller sizes and better heat management as well as application in optoelectronic devices.

Improved imiquimod-induced psoriasis like dermatitis using microneedles in mice.

Psoriasis is a chronic inflammatory skin disease, in which the key features are epidermis hyperplasia, hyper-keratinization, leading to low drug absorption. As an approach of transdermal drug delivery, the microneedle (MN) has received increasing attentions for its painless penetration and efficient administration. In this study, we fabricated polylactic acid polymer MNs with hot-press method and established a psoriasis-like skin inflammation model in ear and dorsal skin of mice by topical application of imiquimod (IMQ). The dynamometer and insertion test of MNs into parafilm and skin of mice were done, revealing that the MNs have sufficient mechanical properties to insert parafilm and skin of mice. The two methods (apply calcipotriol (CAL) directly and pre-treat with MNs before applying CAL) were used to treat psoriasis and observe the skin inflammation, including skin and epidermal thickening, spleen weight gain, inflammatory cell infiltration, and expression of inflammatory cytokines of TNF-α. Both methods have a therapeutic effect and the effect of the MN pretreatment group is better. In addition, there are statistical differences between the two groups (P < 0.05). These features indicated that the MNs may be promising in future clinical applications in improving the imiquimod-induced psoriasis like dermatitis.

Simulation study of the pH sensitive directed self-assembly of rheins for sustained drug release hydrogel.

The hydrogel formed by the directed self-assembled rhein molecules at an appropriate pH value for sustained drug release has been reported recently. Although the application in drug therapy has been experimentally verified, the research on the mechanism of the self-assembly by rhein is still incomplete. In this study, we provide a new insight of the pH-induced self-assembly mechanism employing the dissipative particle dynamics (DPD) as well as multiscale molecular simulations. It comes to the conclusion that protonated rheins incline to aggregate, so spherical, columnar, and membrane-shaped aggregated micelles can be observed with the mounting drug concentrations. However, the thermodynamic solubility of these structures is relatively weak, which ultimately causes the system to precipitate. While, driven by the better hydrophilicity and charge effect of the deprotonated rheins, the self-assembly conformation of deprotonated rheins grows through a sphere, wormlike, long wormlike manner, resulting in a host of discontinuous and highly dispersive morphologies. Those structures, having good thermodynamic solubility though, cannot provide the required mechanical properties, thus the rhein system can only exist in the aqueous solution state. Only when the value of pH is moderate (the corresponding degree of deprotonation is 36 %-60 %), could a continuous network self-assembled structure be obtained, leading to the formation of hydrogel to meet the clinical requirements.

Effect of polymer microneedle pre-treatment on drug distributions in the skin in vivo.

Solid microneedles (MNs) represent a useful tool for enhancing skin permeability by creating microchannels that provide a drug delivery route. To achieve the solid polymer MNs to become a clinical reality and to be commercialised, it is much essential to understand the skin penetration process. In this work, the effect of polymer MN height and density, drug molecular weight, as well as drug diffusion time on the drug permeability distribution was systemically investigated in vivo. MN with a height of 800 µm was most conductive to enhance the vertical distribution of drug permeation into the skin, while 11 × 11 MN array was most beneficial to promote the horizontal distribution of drug permeation into the skin. In addition, the increasing of drug molecular weight could reduce the drug permeability distribution and Fluorescein isothiocyanate most likely to penetrate into the skin after MNs pre-treatment. With the increase of drug diffusion time, the drug distribution in the subcutaneous gradually weakened until the drug was absorbed by the subcutaneous tissue at 8 h. These results suggest that the solid polymer MNs can penetrate the stratum corneum of the skin for enhancing drug delivery, especially small molecule drugs.

Multiscale simulations of drug distributions in polymer dissolvable microneedles.

Drug distribution in polymer dissolvable microneedles (MNs) is essential for enhancing the efficiency of drug delivery. In the present work, multiscale simulation was applied to study the interactions between polymer and drug molecules, which may influence the drug distribution in the MNs. In this study, Hyaluronic acid (HA) and Polyvinyl alcohol (PVA) were used to fabricate the MNs and sulfonhodamine B (SRB) was selected as the model drug. Firstly, from the quantum chemical calculations, the global electronegativity of HA (3.786 eV) is stronger than that of PVA (2.435 eV), which means that HA owns stronger electronegativity. The Flory-Huggins parameter of HA-SRB is -1.16 which is lower than that of PVA-SRB (53.51), indicating that HA has better compatibility with SRB molecules than PVA. From molecular dynamic simulations, the binding energy of HA-SRB is 93.52 kcal/mol which is much higher than that of PVA-SRB (-2.40 kcal/mol), meaning that HA is easier than PVA to combined with SRB. The mesoscale-based dissipative particle dynamics (DPD) simulations were applied to visualize the diffusion behavior of SRB and the swelling properties of the polymers. All the results indicated that SRB has a lower diffusion coefficient in PVA solution than that in HA solution, which may prevent the diffusion of drug from MN tips to the bases, facilitating the fabrication of MNs with drug concentrated MN tips. Finally, the SRB loaded PVA and HA MNs were prepared and the experimental results are consisted with the simulation results.

Knockdown of RTN1-C attenuates traumatic neuronal injury through regulating intracellular Ca2+ homeostasis.

Reticulons (RTNs) are a family of membrane-bound proteins that are dominantly localized to the endoplasmic reticulum (ER) membrane. RTN1-C is one member of RTNs abundantly expressed in the brain and has been shown to mediate neuronal injury in cerebral ischemia models. In the present study, we investigated the role of RTN1-C in an in vitro brain trauma model mimicked by traumatic neuronal injury (TNI) in primary cultured cortical neurons. TNI increased the expression of RTN1-C in cortical neurons but had no effect on RTN1-A and RTN1-B. Knockdown of RTN1-C with specific siRNA (Si-RTN1-C) significantly decreased cytotoxicity and apoptosis after TNI. The results of Ca2+ imaging showed that intracellular Ca2+ overload induced by TNI was attenuated by RTN1-C knockdown. Furthermore, the activation of metabotropic glutamate receptor 1 (mGluR1)-induced Ca2+ response was partially prevented by Si-RTN1-C transfection. We also evaluated the role of RTN1-C in store-operated Ca2+ entry (SOCE) in cortical neurons using the ER Ca2+ inducer thapsigargin (Tg). The results showed that knockdown of RTN1-C alleviated the SOCE-mediated Ca2+ influx and decreased the expression of stromal interactive molecule 1 (STIM1). In summary, the present study found that knockdown of RTN1-C protected neurons against TNI via preservation of intracellular Ca2+ homeostasis, which was associated with the inhibition of mGluR1-mediated ER Ca2+ release and suppression of STIM1-related SOCE. Thus, RTN1-C might represent a therapeutic target for traumatic brain injury (TBI) research.

[Study on the Effects of Alq3:CsF Composite Cathode Buffer Layer on the Performances of CuPc/C60 Solar Cells].

This paper introduces the methods improving the performance and stability of copper-phthalocyanine(CuPc) / fullerene (C60) small molecule solar cells by using tris-(8-hydroxyquinoline) aluminum(Alq3): cesium fluoride(CsF) composite cathode buffer layer. The device with Alq3:CsF composite cathode buffer layer with a 4 wt. % CsF at a thickness of 5 nm exhibits a power conversion efficiency (PCE) of up to 0.76%, which is an improvement of 49%, compared to a device with single Alq3 cathode buffer layer and half-lifetime of the cell in air at ambient circumstance without any encapsulation is almost 9.8 hours, 6 times higher than that of without buffer layer, so the stability is maintained. The main reason of the device performance improvement is that doping of CsF can adjust the interface energy alignment, optimize the electronic transmission characteristics of Alq3 and improve the short circuit current and the fill factor of the device using ultraviolet-visible absorption, external quantum efficiency and single-electron devices. Placed composite cathode buffer layer devices with different time in the air, by comparing and analyzing current voltage curve, Alq3:CsF can maintain a good stability as Alq3. Alq3:CsF layer can block the diffusion of oxygen and moisture so completely as to improve the lifetime of the device.

[Research on synthesis and luminous mechanism of a soluble blue-light luminescence material derived from carbazole].

In the present paper, a kind of blue light-emitting organic small molecule luminescent materials was designed and synthesized, which is composed of carbazole and 8-benzyloxyquinoline functional groups. Alkyl chain can effectively play the role of electron transfer barrier. The synthesis principle was on the basis of the mechanisms of SN1 nucleophilic reaction and SUZUKI coupling reaction mechanisms. It is entitled N-[6-(8-benzylquinoline)-hexyl] carbazole (CzBQ). Its molecular structure was simulated and optimized by Gaussian03. Its chemical structure was identified by measurements of ultraviolet-visible spectra and H1 NMR spectra. It photo physical property was characterized by method of fluorescence spectra. t is indicated that CzBQ was a kind of blue-light luminescence material and its optical band gap is 3.02 eV. Ethanol solution of CzBQ exhibits the maximal emission peak at 410 nm in photoluminescence spectra In the luminescence process of CzBQ, carbazole groups and 8-benzylquinoline groups were separately involved in excitation and light emission. This kind of blue-light luminescence material possesses excellent solubility, It can be dissolved in different solvents such as ethanol and ethyl acetate and dichloromethane. The test results of AFM show that CzBQ was provided with very good film formability. It is expected to be utilized in blue-light organic light-emitting device fabricated by wet method such as spin-coding method and screen printing.

[Molecular structure and luminescent property of bis(2-(4-methyl-2-hydroxyphenyl)benzothiazolate) zinc].

Bis(2-(4-methyl-2-hydroxyphenyl)benzothiazolate) zinc(Zn(4-MeBTZ)2) was synthesized. Its molecular structure was confirmed by single-crystal x-ray diffraction. Single-crystal data are as follows: space group triclinic, P-1; a = 8.989 9(11) angstroms, b =12.161 7 (15) angstroms, c = 12.871 9 (16) angstroms, alpha = 63.492 (2) degrees, beta = 84.825 (2) degrees, gamma =71.187 (2) degrees. The steric hindrance provided by introduction methyl groups on phenoxide ring prohibited effectively the formation of pentacoordinate complex. There is distinct intermolecular pi-pi interaction between molecules. The dihedral angle between the phenol and benzothiazolate rings of Zn(4-MeBTZ)2 is 2.166 degrees. The HOMO energy, LUMO energy and optical gap are -5.84, -3.46 and 2.37 eV, respectively. The maximum wavelength peak of PL spectra located at 470 nm. The double-layer devices were employed using Zn(4-MeBTZ)2 as emitter and NPB as hole-transport material. The EL spectra split into two peaks located at 501 and 544 nm respectively. The broadened EL spectra were demonstrated to be originated from the exciplexes formed at the interface between NPB and Zn(4-MeBTZ)2.

[Synthesis and luminescence properties of europium (III) complexes].

Three types of europium complexes were synthesized by introducing benzoylacetone as the first ligand and 1, 10-phenanthroline, triphenylphosphine oxide, 2,2'-bipyridyl as the second ligand, respectively. The properties of above materials were characterized by infrared absorption spectra, UV-Vis absorption spectra and fluorescence spectra. Then, it was discussed that the different second ligands of europium complexes can affect their luminescence properties, and their intramolecular energy transfer models had been set up. The results indicated that ligands and complexes have a strong absorption of UV light and the three types of europium complexes exhibit characteristic luminescence of europium ion when excited by UV light. In addition, it is suggested that the fluorescence yield of europium complexes mostly depend on both the energy difference between the second ligand and the Eu3+ ion and the energy difference between the second ligand and the first ligand.

[A new type of iridium (III) phenylpyrazole complexes: synthesis, photophysical characterization].

New heteroleptic iridium(III) complexes (ppz)2Ir(LX), which consist of two cyclometalated ligands ppz(1-phenylpyrazole) together with an ancillary ligand LX (LX= 2-(2'-hydroxylphenyl)benzothiazole (BTZ), 2-(3'-methyl-2'-hydroxylphenyl) benzothiazole (3-MeBTZ), 2-(4'-methyl-2'-hydroxylphenyl) benzothiazole (4-MeBTZ) and 2-(4'-Trifluoromethyl-2'hydroxylphenyl) benzothiazole (4-tfmBTZ)), were synthesized and characterized. The molecular structures and photophysical properties were characterized and analyzed comparatively. The results show that the four complexes have basically similar UV-Vis absorption spectra, fluorescence excitation and emission spectra. Their maximum emission peaks are located at 583-615 nm, and accompanied by a lower intensity emission band around 400 nm. The weak emissions around 400 nm are ascribed to the radi ation transition of single state excition from ancillary ligand BTZ perturbed by metallic ion, and light emission around long-wave-length to the radiation transition of 3MLCT of Ir(BTZ) fragment. While the triplet state 3 MLCT of Ir(ppz)2 fragment might be quenched at room temperature. For all complexes, the excitations with maximum efficiency are located at 250-310 nm, which indicates that main contributor to light emitting is ligand-centered absorption (1pi-pi*) of ppz and BTZ rather than 3MLCT transitions, and thus provides a striking evidence that there is intersystem crossing from 1pi-pi* state to 3MLCT state in these complexes. Compared with Ir(ppz)3, these complexes not only have stronger phosphorescence at room temperature but also their emission color can be tuned by modifying ancillary ligand.

[New highly phosphorescent heteroleptic tris-cyclometalated iridium (III) complexes: synthesis and photophysical characterization].

New heteroleptic tris-cyclometalated iridium(III) complexes (ppy)2 Ir(LX) (ppy==2-phenylpyridine, LX==Sal (salicylic acid), Msal (4-methylsalicylic acid), FSal(4-trifluoro methyl salicylic acid)) was synthesized and characterized. The molecular structure, photophysical properties and thermal stability were tested and analyzed. The results show that the absorption peaks were located around 270, 370, 450 and 484 nm respectively at room temperature. The two former peaks at 270 and 370 nm should belong to 1pi--pi* transition at ppy and transition from salicylic acid ligands to 2-phenylpyridine; The peaks around 450 and 484 nm can be assigned to the charge transfer transition from Ir to ligand (1MLCT and 3MLCT) and 3pi--pi* transition respectively. The PL emission peaks were located at 520, 522, and 510 nm, respectively. The emission of (ppy), Ir(Sal) and (ppy), Ir (MSal) was mainly ascribed to the radiation transition of triple state 3MLCT, while the emission of (ppy)2 Ir(FSal) was mainly from the radiation transition between Sal and ppy, partly from the radiation transition of single state 1MLCT and triple state 3MLCT. The quantum efficiencies of these complexes were 0.37, 0.33 and 0.29 respectively. The thermal decomposition temperature was from 306 to 328 degrees C. (ppy)2 Ir(LX), being a series of efficient phosphorescent materials with good thermal stability, can be used in the organic electroluminescent devices.

[Synthesis and spectral properties of polymer of Tis (5, 5'-methylene-bis (8-hydroxy-quinoline) gallium with orange-red light emitting].

A ligand 5,5'-methylene-bis(8-hydroxyquinoline)(Hqq) was synthesized by condensation reaction at low temperature and was subsequently coordinated to gallium ions to prepare the polymer of tis(5,5'-methylene-bis(8-hydroxyquinoline) gallium (Gaqq3)n. Both chemical structure and phase structure of the ligand and complexes were characterized by Infrared absorption spectrum and X-ray diffraction (XRD). The thermal stability of the complexes was studied by thermogravimetry (TG). The photo-physical properties of the complexes were investigated by ultraviolet absorption spectrum (UV), fluorescence excitation spectrum and emission spectrum. The result indicated that (Gaqq3)n is a thermally stable material, whose decomposition temperature is 443.6 degrees C. The ultraviolet absorption bands of (Gaqq3)n are in the range of 250-500 nm, with a relatively strong band tail absorption between 500 and 650 nm, which shows that the band-gap defect states exists in the forbidden band. The fluorescence excitation band of (Gaqq3)n is located at 380-456 nm, and (Gaqq3)n. emits orange-red fluorescence with the emission peak at 568 nm, which shows that the fluorescence emission of (Gaqq3), is mainly attributed to the charge transfer transitions from phenol to ring pyridine ring, while the pi-->pi* transition of benzene ring is deactivated by non-radiative transition, and makes no contribution to fluorescence emission. (Gaqq3)n optical band gap is 2.49 eV. Compared with the fluorescence emission peak of Gaq3, the fluorescence intensity of (Gaqq3), decreases, which is attributed to the distortion of the two quinoline rings connected to the methylene, hence leads to the poor rigidity and coplanarity of (Gaqq3)n, thus affects fluorescence emission intensity. Because of the extending of the molecular conjugation system, pi electron of (Gaqq3)n is more delocalized, resulting in the redshift of fluorescence emission peak (Gaqq3)n is expected to be applied in organic light emitting display and organic photovoltaic devices.

[Studies on a new type structure OELD with interinserting interface].

A new type organic electroluminescent device with interinserting interface was fabricated. The basic structure of the device is ITO/NPB/Alq3/Al. By tailor-made template, the two interinserting interfaces were fabricated with NPB/Alq3 and Alq3/Al, respectively. The charge distribution on the interface and the electric field distribution in the organic layer were changed by introducing interinserting interfaces, thus the electron injection was improved, and the balance of the number of the electrons and holes at the interface was obtained. Therefore, the formation probability of exciton was enhanced and the leakage current was reduced. Compared to the traditional two-layer structure devices, the interinserting structure device has lower turn-on voltage and higher luminous efficiency. The driving-voltage of the interinserting structure OELD decreased while the brightness increased with the increase in the number of the interinsertion. As the current density increased, all the devices with interinserting interface showed high optical-electrical stability. The turn-on voltage of the device e is 3 V, and was made using the three slots template. At the current density of 54 mA x cm(-2), the device e gets its maximum efficiency, which is 34% higher than the traditional structure device a.

[A novel yellow organic light-emitting device].

The fabrication of a novel organic yellow-light-emitting device using Rhodamine B as dopant with double quantum-well (DQW) structure was introduced in the present article. The structure and thickness of this device is ITO/CuPc (6 nm) /NPB (20 nm) /Alq3 (3 nm)/Alq3 : Rhodamine B (3 nm) /Alq3 (3 nm) /Al q3 : Rhodamine B(3 nm) /Alq3 (30 nm) /Liq (5 nm)/Al (30 nm). With the detailed investigation of electroluminescence of the novel organic yellow-light-emitting device, the authors found that the doping concentration of Rhodamine B (RhB) had a very big influence on luminance and efficiency of the organic yellow-light-emitting device. When doping concentration of Rhodamine B (RhB) was 1.5 wt%, the organic yellow-light-emitting device was obtained with the maximum current efficiency of 1.526 cd x A(-1) and the maximum luminance of 1 309 cd x m(-2). It can be seen from the EL spectra of the devices that there existed energy transferring from Alq3 to RhB in the organic light-emitting layers. When the doping concentration of RhB increased, lambda(max) of EL spectra redshifted obviously. The phenomenon was attributed to the Stokes effect of quantum wells and self-polarization of RhB dye molecules.

[Characterization and photoluminescence properties of an azomethin-zinc complex].

A Schiff base organic metal complex, Bis(salicylidene)-1,2-phenylenediam-ine Zinc(II) with high purity, was synthesized and purified by vacuum sublimation. Its structure, thermal stability and energy band structure were investigated by element analysis, FTIR spectra, TG-DTA curve, UV-Vis absorption spectra, fluorescece emission spectra and PL spectra. Experimental results showed that the complex is a thermally stable, polycrystalline material, with glass temperature and decomposition temperature being 183 and 449 degrees C, respectively. In its infrared spectrum, a high intensity band was at about 1 385 cm(-1). This band was typical of the conjugated C=N stretching vibration, which shifted to higher frequency in relation to the free ligand of salicylaldehyde with 1,2-phenylenediamine. The new bnd at 529 cm(-1) was assigned to Zn-O stretching vibration. Its UV absorption bands were at about 297 and 406 nm, and its tetrahydrofuran solution emitted intensive blue-green fluorescence at the peak wavelength of 508 nm. The absorption band at about 406 nm can be assigned to the intrinsic absorption of C=N. Its optical gap was about 2.62 eV, which was determined by the intrinsic absorption band edge of the complex in tetrahydrofuran solution. Under UV excitation at 365 nm, the complex in film emitted yellow-green fluorescence with the maximum emission peak at 562 nm and a full-width at half-maximum of 48.5 nm in PL spectra. Finally, yellow organic light-emitting devices using this complex as the emissive layer were fabricated and investigated.

[Spectroscopic properties of salicylaldehyde anil zinc and its thin film].

A new light emitting material, salicylaldehyde anil zinc (SAZ), was synthesized. It can form high quality nano-scale amorphous thin films on clean glass substrates by vacuum evaporation. Its structure, crystallization, thermal stability, and optical property were investigated by IR spectra, DTA-TG analysis, XRD spectra, UV-Vis spectra, and fluorescence spectra. Its energy band structure was confirmed by cyclic voltammogram and optical absorption band edge. Results show that the SAZ film is a thermally stable material, and can emit intense green fluorescence with a peak wavelength at 508 nm and a full width at half-maximum of 90.2 nm under UV irradiation. Its HOMO energy level is about -5.659 eV, LUMO energy level is about -3.054 eV, optical gap band is about 2.604 eV. The fluorescence decay of stored films under ambient atmosphere is more rapid than that of 8-hydroxyquinoline aluminum films. However, the fluorescence decay of the films under UV irradiation is slower than that of 8-hydroxyquinoline aluminum films.

[Spectral analysis and photoluminescence properties of 1,5-naphthalene diamine derivative].

In the present paper, 1,5-bis[N-(1-naphthyl)-N-phenyl] naphthalene diamine (NPN) with high purity was synthesized by liquid-phase Ullmann reaction, and high quality film of NPN was formed on cleaned glass substrates by vacuum evaporation. Photoluminescence properties were studied by solvent effects on UV-Vis absorption spectra and fluorescence spectra. In addition the structure of energy band of NPN was studied by cyclic voltammetry, UV-Vis absorption spectra, and fluorescence spectra. The results indicate that the fluorescence emitting is attributed to the charge transfer transition from nitrogen to aromatic ring. The molecules of NPN in its film form "J-aggregate". The HOMO energy and optical gap of NPN are -5.74 and 2.79 eV respectively. NPN film could emit intense blue fluorescence with a peak wavelength at 448.6 nm and a bandwidth of 72.6 nm under UV-Vis excitation at 365 nm.

[Preparation and spectral analysis of a new type of blue light-emitting material delta-Alq3].

In the present article, delta-Alq3, a new type of blue light-emitting material, was synthesized and investigated by IR spectra, XRD spectra, UV-Vis absorption spectra, photoluminescence (PL) spectra, and electroluminescence (EL) spectra. The relationship between molecular spatial structure and spectral characteristics was studied by the spectral analysis of delta-Alq3 and alpha-Alq3. Results show that a new phase of Alq3 (delta-Alq3) can be obtained by vacuum heating alpha-Alq3, and the molecular spatial structure of alpha-Alq3 changes during the vacuum heating. The molecular spatial structure of delta-Alq3 lacks symmetry compared to alpha-Alq3. This transformation can reduce the electron cloud density on phenoxide of Alq3 and weaken the intermolecular conjugated interaction between adjacent Alq3 molecules. Hence, the pi--pi* electron transition absorption peak of delta-Alq3 shifts toward short wavelength in UV-Vis absorption spectra, and the maximum emission peak of delta-Alq3 (lamda max = 480 nm) blue-shifts by 35 nm compared with that of alpha-Alq3 (lamda max = 515 nm) in PL spectra. The maximum emission peaks of delta-Alq3 and alpha-Alq3 are all at 520 nm in EL spectra.