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With increasing utilization of digital multimedia and the Internet, protection on this digital information from cracks has become a hot topic in the communication field. As a path for protecting digital visual information, image encryption plays a crucial role in modern society. In this paper, a novel six-dimensional (6D) hyper-chaotic encryption scheme with three-dimensional (3D) transformed Zigzag diffusion and RNA operation (HCZRNA) is proposed for color images. For this HCZRNA scheme, four phases are included. First, three pseudo-random matrices are generated from the 6D hyper-chaotic system. Second, plaintext color image would be permuted by using the first pseudo-random matrix to convert to an initial cipher image. Third, the initial cipher image is placed on cube for 3D transformed Zigzag diffusion using the second pseudo-random matrix. Finally, the diffused image is converted to RNA codons array and updated through RNA codons tables, which are generated by codons and the third pseudo-random matrix. After four phases, a cipher image is obtained, and the experimental results show that HCZRNA has high resistance against well-known attacks and it is superior to other schemes.

Six new triorganotin 3‐(salicylideneamino)benzoates (1a–1c) and 3‐(4‐oxo‐2‐penten‐2‐ylamino)benzoates (2a–2c), 3‐(2‐HOC6H4CH=N)C6H4COOSnR3, and 3‐(CH3COCH=C(CH3)NH)C6H4COOSnR3 (R = Ph, a; Cy, b; Bu, c) have been synthesized by one‐pot reaction of 3‐aminobenzoic acid, salicylaldehyde (or 2,4‐pentanedione), and triorganotin hydroxide and characterized by elemental analysis, infrared, and nuclear magnetic resonance (1H, 13C, and 119Sn) spectra. The crystal structures of 1a, 1b, and 2a–2c have been determined by the single crystal X‐ray diffraction. Complexes 1a and 2a exhibit a 44‐membered macrocyclic tetramer and a polymeric zigzag chain, respectively, in which tin atoms show trans‐[C3SnO2] trigonal bipyramidal geometry with the axial positions being occupied by the carboxylate oxygen atom and the phenolic (or ketone) oxygen atom from another ligand. Complex 1b adopts a distorted tetrahedral geometry at tin, and there are two molecules differing in the relative orientation of the carboxylate toward the imino group. Compounds 2a⋅CH3OH, 2b⋅H2O, and 2c⋅H2O are five‐coordinated mononuclear adducts with one coordinated solvent molecule and display different supramolecular organizations in which there are the centrosymmetric R22(16), R42(22), and R64(34) macrocycle motifs formed by the O–H⋅⋅⋅O, N–H⋅⋅⋅O, and C–H⋅⋅⋅O hydrogen bonds. The fluorescence spectrum indicates that the complexes may be explored for potential blue luminescent materials. Compared to cisplatin, these compounds exhibit enhanced cytotoxic efficacy and can be considered as anticancer agents for further study.

BACKGROUND: The development of innovative approaches in drug analysis is a challenging task for medicine, pharmacy, and engineering sciences. For instance, requirement of proper dosage forms in releasing active ingredients is crucial. It is essential to analyze drugs in biological liquids for early diagnosis and treatment purposes. Drug analysis is also of great importance to control the quality of pharmaceutical products, test their efficacy, and develop novel drug formulation. The present review is aimed to highlight the most recent spectrophotometric approaches applied to analyze various classes of drugs in biological media and/or dosage forms. METHODS: As well as direct and derivative UV/UV–Vis spectrophotometry, combination of various techniques with spectrophotometry, such as injection analysis and chemometrics, has been most widely applied in the analysis of dosage forms. In addition, emerging technologies, such as UV imaging allowing to obtain the distribution of drug concentration in a time-resolved 2D images based on UV light absorption, utilization of nanotechnology, self-assembled nanomaterials, and aptamer-based nanoparticles have been gained interests to investigate drug assays and to quantify the proper drug release. RESULTS: Due to their high versatility, ease of application, low cost, and fast response, spectrophotometric methods are one of the most preferable methods providing high accuracy and precision with a wide linear range in drug analysis. CONCLUSION: Selected examples demonstrating the applicability of spectrophotometric methods in pharmaceutical assays in this review might contribute to the overall importance of the analytical test used in the modern pharmaceutical analysis.

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Background: The number of validated quantification methods for rifampicin, a prototypical Oatp inhibitor, in biological rat samples was limited. Objective: This study was conducted to validate a modified reversed-phase liquid chromatographic method for the determination of rifampicin in rat liver tissue according to the current ICH M10 Bioanalytical Method Validation Draft Guideline (2019) for application to samples of in situ rat liver perfusion studies. Method: Liver tissue samples were obtained from recirculatory in situ rat liver perfusion studies. The analysis was performed on a C18 column with a mobile phase composed of 0.05 M phosphate buffer (pH 4.58): acetonitrile (55:45, v/v). The assay was validated for selectivity, calibration curve and range, matrix effect, carry-over, accuracy and precision, reinjection reproducibility, and stability. Results: The method was considered selective and stable, without having carry-over and matrix effects. The calibration curve was linear (R2: 0.9983) within the calibration range (0.5-60 ppm). Accuracy and precision values fulfilled the required limits. Liver concentrations of rifampicin in liver tissue, obtained after 60 min perfusion with 10 µM and 50 µM of rifampicin were 45.1 ± 11.2 and 313.4 ± 84.4 µM, respectively. Conclusion: The bioanalytical method validation was completed and the method was successfully applied for the determination of rifampicin in rat liver tissue.

Introduction: OC26, an ortho-aryl chalcone compound, shows excellent antitumor activity in vitro and vivo. However, the pharmacokinetic characteristics of OC26 have not been comprehensive reported. It is essential for investigated the correlation of pharmacological response. Objective: To further explorer of OC26, this study aims to develop an ultra-performance liquid chromatography tandem mass spectrometric (UPLC-MS/MS) method to reveal the pharmacokinetics and distribution characteristics in rats of OC26. Method: An UPLC-MS/MS method was developed to detect OC26 in plasma and various tissues. Protein precipitation method was applied to process the biological samples. After intravenous injection 12.5mg/kg of OC26 in rats, plasma and tissues samples were collected from rats and the method was applied to investigate pharmacokinetic and distribution characteristics of OC26. Results: Calibration curve samples of OC26 concentration ranging from 20 to 2000 ng/mL with the goodness of fit (r2 > 0.99). The precisions for the method were within 12.3%, while the accuracies for the method were within ±11% (bias). Matrix effect had no influence on the accuracy and precision of the method. After intravenous injection 12.5mg/kg of OC26 in rats, OC26 was rapidly eliminated (t1/2=31.39±7.87min, MRT0→∞=15.03±2.55min) from rat plasma and widely distributed (Vd=4.83±0.96L/kg) in tissues. The highest concentration of OC26 was detected in brain which peak content (~8962.78ng/g at 15min) was over 5-fold higher than that of in other tissues, which prompted new potential target in brain. Besides, lung and heart were also detected quite high level of OC26. Benefited from quick elimination in collected tissues and plasma, long-term accumulation was not observed that chronic toxicity might be less. Conclusions: This UPLC-MS/MS method was successfully applied to detect OC26 and provided a theoretical basis for the further study of OC26.