Blue Emission of Tetrafluorobenzocarbazole Under the Interactions of Nitrogen-oxygen Saturated hydrogen Bonds with Aggregated Proton Acid.

Two novel tetrafluorobenzocarbazole and containing the amino branch introduced at the end of the molecule are synthesized by a simple method. The tetrafluorobenzocarbazole as the electron donor with electron-rich fluoride ions connected by π-benzyl ring conjugation structure, which affects the overall electron cloud density. Moreover, the amino branch introduced at the end of the molecule, which makes it easy to form intermolecular hydrogen bonds and affected photophysical properties. Meanwhile, the photophysical property of both compounds are discussed under different acidic conditions. The UV-absorption show that around ~286 nm is mainly attributed to the strong structural absorption band peak of the π-π ∗ transition of the carbazole moiety, and the irregular absorption band around ~314 nm and ~326 nm are mainly attributed to the n-π ∗ transition of the carbazole group conjugate with the adjacent molecule. The emission spectrum of both compounds showed that the intensity of fluorescence decreased in different degrees after the addition of the acidic solution. Furthermore, the electrochemical properties were evidenced by cyclic voltammetry (CV) and density functional theory (DFT) calculations, and the orbital conformation (HOMOs-LUMOs) was simulated by Gaussian 09 software and its crystal structure was observed by X-ray diffraction (XRD). The results exhibited that both compounds are electrochemically stable blue small-molecule fluorescent substances, and expected that both compounds can be novel and stable acid-sensitive organic blue-light materials.

Strategy of eudragit coated curcumin nanoparticles delivery system: Release and cell imaging studies in simulated gastrointestinal microenvironments.

Curcumin has a broad-spectrum anti-tumor effect and has no toxic side effects. However, the unique diketone structure of curcumin will undergo diketo-enol tautomerism under different acid-base conditions, resulting in its instability under physiological conditions. In addition, the low biocompatibility and absorption rate of curcumin also limit the use of curcumin drugs. In this paper, curcumin was modified by substitution of acryloyl and acrylsulfonyl groups, and four kinds of nanoparticles with regular morphology were prepared using non-toxic and non-irritating acrylic resin as coating material to improve the stability and bioavailability of the compounds. Zeta potential testing shows that the composites surface carries positive charges and have good stability. In the release experiment, four complexes have the potential for slow and controlled release. Imaging of Hela cells with different channels was performed, and the imaging results showed that the complexes could enter the cells and be absorbed by them, demonstrating good imaging performance. MTT experiments have shown that the complexes have certain anti-tumor activity and low cytotoxicity. In general, the complexes synthesized in this paper have potential in the field of drug fluorescence imaging detection. At the same time, this experiment provides a new idea for the design of slow and controlled release of drugs.

A novel strategy to bind pyrimidine sulfonamide derivatives with odd even chains: exploration of their design, synthesis and biological activity evaluation.

Based on the hybridization strategy of dominant fragments, a series of pyrimidine sulfonamide (PS) derivatives were obtained by combining the pharmacophore fragments (sulfonamide group and pyrimidine group) with different biological activities, and evaluated as a new type of anticancer drug. The compounds were evaluated for in vitro cytotoxicity against four human cancer cell lines (HeLa, HCT-116, A-549 and HepG2) and the normal human cell line L02. Compared with the anti-cancer drug 5-fluorouracil (5-FU), the antiproliferative activity of compound PS14 was close to 5-FU and it has good antitumor activity. The IC50 values were 15.13 ± 2.20, 19.87 ± 2.01, 12.64 ± 3.22, 22.20 ± 1.34 and 102.46 ± 2.27 µM, respectively. The structure activity relationship was analyzed. The antitumor activity of the compound tended to increase. When the substituents of the branch chain of sulfonamides were odd. In addition, the oil-water partition coefficient was also investigated. The logP value of PS14 was between 0 and 3, indicating that PS14 was a compound with good lipophilic property, poor water solubility and easy to be absorbed and transported through cell membrane. The anti-cancer mechanism was further studied by flow cytometry. After PS14 treated HeLa, HCT-116, A-549 and HepG2, the percentage of apoptotic cells was 45.30%, 28.2%, 31.00% and 35.20%, respectively, which was higher than that of the control 5-FU. The results of cell cycle showed that PRD2 mainly blocked the cell cycle in the S phase, thereby inhibiting cell proliferation. Furthermore, molecular docking analyzed possible interactions between the compound and the PI3Kα active site, this compound has good binding with PI3Kα. Overall, this study laid the groundwork for the development and structural modification of new pyrimidine sulfonamide drugs, and PS14 could be further developed into a cancer treatment drug.

Spectral-envelope modulated double-phase method for computer-generated holography.

Computer-generated holography provides an approach to modulate the optical wavefront with computationally synthesized holograms. Since the hardware implementation for complex wavefronts is not yet available, double-phase decomposition is utilized as a complex encoding method of converting a complex wavefront to a double-phase hologram. The double-phase hologram adapts a complex wavefront for the phase-type devices, but the reconstruction is plagued by the noise caused by spatial-shifting errors. Here, a spectral-envelope modulated double-phase method is proposed to suppress the spatial-shifting noise with an off-axis envelope modulation on the Fourier spectrum of a double-phase hologram. This proposed method out-performs conventional on-axis double-phase method in optical reconstructing accuracy with indicated 9.54% improvement in PSNR and 196.86% improvement in SSIM.

Water-soluble BODIPY-nido-carborane nanoparticles applied to biocompatibility tumor cell imaging.

In this article, o-carborane has a high boron content, high hydrophobicity, and good chemical stability. It has been widely used in the fields of biology and medicine, especially in the application of boron neutron capture therapy (BNCT). However, o-carborane is a fat-soluble compound, its hydrophobicity is too strong, and its bioavailability is poor. This project aims to improve the water solubility of o-carborane drugs, so that the drugs can reach specific sites. For this reason, this article provides a one-pot reaction for the synthesis of water-soluble boron-containing drugs. 2-Chloro-1-(difluoroboranyl)-5-((4-ethyl-3,5-dimethyl-2H-pyrrol-2-ylidene)(phenyl) methyl)-1H-pyrrole and ethylenediamine are used as raw materials to synthesize fluorescent molecular probe BODIPY-NH2, and the fluorescent molecular probe is reacted with P-CBMA (poly(carboxybetaine methacrylate)) to produce a water-soluble gel polymer. Water-soluble o-carborane polymers were synthesized by hydrogen bonding of the polymers with bis(4-azaspiro[3.4]octan-4-ium)-nido-ortho-carborane and bis(5-azaspiro[4.5]decan-5-ium)-nido-ortho-caborane. The two polymers were characterized and the results showed that the maximum UV absorption wavelength of the two boron polymers in different polar solutions was 530-540 nm. In the fluorescence spectrum, the maximum emission wavelengths of the two boron polymers are concentrated between 550 and 560 nm. Through electron microscopy imaging, the fluoroboron pyrrole polymers wrap the boron clusters to form a spherical stacked. Through fluorescent cell imaging, both boron polymers can enter target cells.

Bioactivity and Cell Imaging of Antitumor Fluorescent Agents (Curcumin Derivatives) Coated by Two-Way Embedded Cyclodextrin Strategy.

Curcumin has a wide range of pharmacological activities, which can be used to treat tumors, inflammation and other diseases. However, curcumin's poor solubility and low bioavailability limit its application. In this article, the structure of curcumin was modified with boron trifluoride ether to change fluorescent labeling. The compounds were then embedded into the hydrophobic cavity of α-cyclodextrin and hydroxypropyl ß-cyclodextrin to form inclusion complexes. The two inclusion complexes have excellent photophysical properties, and the maximum emission wavelength is in the range of 550-565 nm. In addition, the two compounds were applied to the fluorescence imaging of HCT-116 cells and HeLa cells, and the proliferation toxicity of the compounds was detected. Both compounds showed certain inhibitory effects on the proliferation of cancer cells. In short, the fluorescent drug molecule synthesized in this article has great reference value for the development of new dosage forms of curcumin.

Combination of Structured Illumination Microscopy with Hyperspectral Imaging for Cell Analysis.

Existing structured illumination microscopy (SIM) allows super-resolution live-cell imaging in few color channels that provide merely morphological information but cannot acquire the sample spectrum that is strongly relevant to the underlying physicochemical property. We develop hyperspectral SIM which enables high-speed spectral super-resolution imaging in SIM for the first time. Through optically mapping the three-dimensional (x, y, and λ) datacube of the sample to the detector plane, hyperspectral SIM allows snapshot spectral imaging of the SIM raw image, detecting the sample spectrum while retaining the high-speed and super-resolution characteristics of SIM. We demonstrate hyperspectral SIM imaging and reconstruct a datacube containing 31 super-resolution images of different wavelengths from only 9 exposures, achieving a 15 nm spectral resolution. We show time-lapse hyperspectral SIM imaging that achieves an imaging speed of 2.7 s per datacube-31-fold faster than the existing wavelength scanning strategy. To demonstrate the great prospects for further combining hyperspectral SIM with various spectral analysis methods, we also perform spectral unmixing of the hyperspectral SIM result while imaging the spectrally overlapped sample.

Shifted band-extended angular spectrum method for off-axis diffraction calculation.

The shifted band-extended angular spectrum method (Shift-BEASM) is proposed to calculate free-space diffraction between two parallel planes with an off-axis offset. Off-axis numerical propagation is useful for simulating non-paraxial and large-scale fields. The proposed Shift-BEASM allow us to calculate the off-axis diffraction in a wide propagation range by extending the effective bandwidth using the nonuniform fast Fourier transform. The calculation accuracy is higher than that of existing techniques, such as the shifted-Fresnel method and shifted band-limited angular spectrum method, not only in the near field but also in the far field. Numerical examples and accuracy as well as theoretical formulation are presented to confirm validity of the proposed method.

Simultaneous improvement of field-of-view and resolution in an imaging optical system.

A novel imaging system design is proposed, in which the FOV and maximum resolution are improved simultaneously while the detector remains fixed. These improvements are realized using freeform optical surfaces and field-dependent characteristic parameters. The resulting imaging system design has optical properties that vary continuously with the field angle. In the central FOV, the system is equivalent to a long-focal-length camera, while in the marginal FOV, it is equivalent to a short-focal-length camera; however, the system has a constant F-number across the FOV. A 2× variation in the field-dependent characteristic parameters across the FOV is achieved.

Optimal quantization for amplitude and phase in computer-generated holography.

Owing to the characteristics of existing spatial light modulators (SLMs), the computer-generated hologram (CGH) with continuous complex-amplitude is conventionally converted to a quantized amplitude-only or phase-only CGH in practical applications. The quantization of CGH significantly affects the holographic reconstruction quality. In this work, we evaluated the influence of the quantization for both amplitude and phase on the quality of holographic reconstructions by traversing method. Furthermore, we considered several critical CGH parameters, including resolution, zero-padding size, reconstruction distance, wavelength, random phase, pixel pitch, bit depth, phase modulation deviation, and filling factor. Based on evaluations, the optimal quantization for both available and future SLM devices is suggested.

Band-limited double-phase method for enhancing image sharpness in complex modulated computer-generated holograms.

Herein, we propose a band-limited double-phase method to improve the quality of reconstructed images encoded by double-phase holograms (DPHs) derived from complex-amplitude light waves. Although the quality of images produced by DPHs was improved compared to that of conventional holographic images, it still suffered from degradation because of the spatial shifting noise generated during the conversion from complex-amplitude holograms to phase-only holograms. The proposed method overcomes this shortcoming by defining a band-limiting function according to the spatial distribution of DPHs in the frequency domain to remove the specific spatial frequency components severely affected by the spatial shifting of DPHs. The sharpness of images reconstructed from band-limited DPHs with appropriate optical filtering showed an improvement of 36.84% in simulations and 51.67% in experiments evaluated by 10-90% intensity variation.

Phase hologram optimization with bandwidth constraint strategy for speckle-free optical reconstruction.

An iterative method with bandwidth constraint strategy is proposed to design phase holograms for high-quality speckle-free optical reconstruction. The bandwidth properties of the reconstructed field are analyzed theoretically based on the sampling theory, which helps in properly allocating the sampling resources for efficiently describing the speckles and artifacts in the reconstructed field. Iterative calculation with bandwidth constraint strategy of the reconstructed field and quadratic initial phase can optimize the phase hologram without stagnation problem, which provides effective controls of the reconstructed intensity fluctuations and helps to suppress the speckles and artifacts. Numerical and optical experiments have been performed to validate the proposed method can achieve excellent image fidelity.

Imaging spectrometer with single component of freeform concave grating.

In this Letter, an imaging spectrometer in which a freeform concave grating is the only optical component in the system is introduced. The degrees of freedom of optical freeform surfaces and a variable line-spacing (VLS) grating are used to realize imaging spectrometers. A point-by-point system design method is proposed that can generate a good initial solution rapidly. By exploring the limitations of the system specifications, it is demonstrated that the spectral dispersion, spectral resolving power, and system length can be improved significantly by using the freeform VLS concave grating. It is also found that freeform surfaces with higher degrees of freedom than a toroid can further improve system performance when using a VLS grating.

Design, synthesis and biological activity of bis-sulfonyl-BODIPY probes for tumor cell imaging.

In recent years, BODIPY derivatives have become one of the research hotspots in the field of bioprobes, but most of them have the problems of poor hydrophilicity, low biocompatibility and no targeting. In this paper, novel ethylenediamine bridging bis-sulfonyl-BODIPY fluorescent probes were successfully designed and synthesized to solve these problems; What's more, the cytotoxicity analysis, cell imaging, in vivo imaging and apoptosis experiments were carried out. Ethylenediamine bridges and oxygen-rich sulfonyl groups made such probes had certain hydrophilicity, so they could be dissolved in dimethylsulfoxide and methanol. The IC50 value of compound 9 in HCT-116 cells was 93.12 ± 6.33 µM, and in HeLa cells was 89.09 ± 11.84 µM, which indicating that the probe had certain inhibitory effect on cancer cells. The excellent biocompatibility and potential tumor targeting properties of the compound were clearly observed in cell and mice imaging. This study is of great significance for the rational design of novel targeted BODIPY probes with good hydrophilicity and biocompatibility.

A multiple acetal chalcone-BODIPY-based fluorescence: synthesis, physical property, and biological studies.

Fluorescent probes with outstanding physical and biological properties are superior for functional fluorescent dyes design. However, few studies pay attention to the stability of specific groups in fluorescent probes. The aldehyde group in the fluorescent probe is highly active but unstable under certain conditions. Therefore, we introduced ethoxy groups to realize the conversion to aldehyde groups under acidic conditions and avoid the instability of straightforward aldehyde groups. In this work, two fluorophores based on the multi acetal difluoroboraindacene (BODIPY) units with combination of the pharmaceutical intermediate chalcone have been firstly developed. In the design part, chalcone was introduced as a medium for fluorophore and multiple acetal. The mild synthesis strategy is based on the ligand ((Z)-2-chloro-1-(difluoroboranyl)-5-((4-ethyl-3,5-dimethyl-2H-pyrrol-2-ylidene)(phenyl)methyl)-1H-pyrrole) and connects with chalcone in (2E,2'E)-3,3'-(1,3-phenylene)bis(1-(2,4-bis(2,2-diethoxyethoxy)phenyl)prop-2-en-1-one). The emission wavelengths of the products are around 530 nm with high fluorescence intensity. To highlight the biological characteristics of these novel BODIPY fluorescents, we further demonstrated biological analysis studies on MTT and flow cytometry assays. The IC50 values of BODIPY 5 ranged from 79 ± 6.11 to 63 ± 5.67 µM and BODIPY 6 were found to be 86 ± 4.07 to 58 ± 10.51 µM in tested cell lines. Flow cytometry data analysis shows that the representative agent 6 and reference have similar rational apoptosis rates in first quadrant. Last but not least, 6 shows outstanding biological compatibility and cell imaging potential in live cell imaging and in vivo assay, not only is the fluorescence prominent enough, but also rapidly distributes. Thus, our study reports a mild synthesis strategy and full biological analysis on BODIPY fluorescents, and the subtle modulation of the physical and biological properties by pharmaceutical substituents makes these designed chalcone-BODIPY-based dyes hopeful to realize drug functional fluorescent dyes. Two new highly sensitive BODIPY fluorophores are synthesized based on the ligand ((Z)-2-chloro-1-(difluoroboranyl)-5-((4-ethyl-3,5-dimethyl-2H-pyrrol-2-ylidene)(phenyl)methyl)-1H-pyrrole), which connects with chalcone in (2E,2'E)-3,3'-(1,3/4-phenylene)bis(1-(2,4-bis(2,2-diethoxyethoxy)phenyl)prop-2-en-1-one). Multiple acetals were introduced and the physical and biological properties of BODIPYs are described with MTT assay and in vitro and in vivo imaging.

High activity, high selectivity and high biocompatibility BODIPY-pyrimidine derivatives for fluorescence target recognition and evaluation of inhibitory activity.

BODIPY-Pyrimidine (BP) is a highly selective, highly active, and highly biocompatible fluorescent drug, which is characterized by its own activity combined with a fluorophore. The combination of pyrimidines with good biological activity and fluorophores to obtain new compounds with both anti-tumor activity and fluorescent targeting probe functions is the focus of this research. In terms of biological activity, in vitro cytotoxicity of the compounds on four human cancer cells (HepG2, HeLa, A-459, and HCT-116) and the human normal cell line L-02 was studied. BP-4 has good antiproliferative activity, and its IC50 values are 19.12 ± 2.29, 13.47 ± 3.80, 18.59 ± 7.42, 14.57 ± 2.44 and 92.48 ± 6.03 µM, respectively. Good biocompatibility with tumor cells can be observed in cell imaging. The anti-tumor mechanism of the compound was further studied by flow cytometry. After BP-2, BP-3 and BP-4 treated HeLa cells, the percentage of apoptotic cells was 19.07%, 22.09% and 27.3%, respectively. The cell cycle study found that, compared with the positive control 5-FU (48.05%), the compounds BP-2, BP-3 and BP-4 all increased the proportion of HeLa cells in the G1 phase, reaching 57.65%, 55.46% and 53.58%, respectively. In vivo bioimaging results show that all three compounds can be targeted and accurately expressed in tumor tissues. In addition, molecular docking analyzes the possible interaction between the compound and the active site of thymidylate synthase.

Frequency-based optimized random phase for computer-generated holographic display.

Random phases with all frequency components lead to excessive diffusions of object waves, resulting in loss of detail in holographic reconstructions. In this study, the effects of random phases with various frequencies on holographic reconstruction results are evaluated. The optimized maximal value of the random phases is analyzed. Utilizing the evaluation results, we propose a frequency-based optimized random phase that reduces the unfavorable effect of the insufficient dynamic range of computer-generated holograms and prevents excessive diffusions by traditional random phases. Utilizing the optimized random phase, which improves the reconstruction quality significantly, we can commendably reconstruct both contours and details.

Frequency sampling strategy for numerical diffraction calculations.

Diffraction calculations play an essential role in Fourier optics and computational imaging. Conventional methods only consider the calculation from the perspective of discrete computation which would either cause error or sacrifice efficiency. In this work, we provide a unified frequency response analysis from the joint physics-mathematics perspective and propose corresponding adaptive frequency sampling strategies for five popular diffraction calculation methods. With the proposed strategies, the calculation correctness is guaranteed and the calculation efficiency is improved. Such an idea of unified frequency response study would help researchers make a do-it-yourself analysis for various diffraction calculation tasks and choose or develop a method for accurate and efficient computations of the diffraction fields.

Non-iterative phase hologram generation with optimized phase modulation.

A non-iterative algorithm is proposed to generate phase holograms with optimized phase modulation. A quadratic initial phase with continuous distributed spectrum is utilized to iteratively optimize the phase modulation in the reconstruction plane, which can be used as an optimized phase distribution for arbitrary target images. The phase hologram can be calculated directly according to the modulated wave field distribution in the reconstruction plane. Fast generation of the phase holograms can be achieved by this non-iterative implementation, and the avoidance of the random phase modulation helps to suppress the speckle noise. Numerical and optical experiments have demonstrated that the proposed method can efficiently generate phase holograms with quality reconstructions.

Adaptive-sampling angular spectrum method with full utilization of space-bandwidth product.

As convolution-based diffraction calculation methods, Rayleigh-Sommerfeld convolution and the angular spectrum method (ASM) usually require zero padding to avoid circular convolution errors. This greatly increases the computational complexity and wastes a large amount of the sampling points. In this Letter, based on the analysis of sampling properties in the convolution process, we propose an adaptive-sampling ASM, which can adjust the sampling parameters according to the propagation distance to avoid circular convolution errors without zero padding. The sampling condition of the transfer function can be adaptively satisfied by rearranging the sampling points in the spatial frequency domain. Therefore, the computational complexity is significantly reduced, and all the sampling points are effectively used, which leads to a full utilization of the space-bandwidth product.