Collagen of porcine auricle has unique biochemical and biophysical characteristics

Collagen is a major component of the extracellular matrix and is used as a material in tissue engineering. We demonstrated the extraction of atelocollagen from porcine auricular and characterized its unique physical and biochemical properties. Extracted type I collagens of auricular collagen using acetic acid and pepsin (PAC) showed superior fibrillogenesis and viscoelasticity compared to type I collagen from porcine skin. The observation of PAC fibrils by transmission electron microscopy and Atomic Force Microscope under physiological conditions revealed long fibrils with pronounced 3D structures, while type I collagen from porcine skin revealed a flat structure. Furthermore, a PAC-coated plate promoted higher cell proliferation than when grown on a skin type I collagen-coated plate. Porcine auricular type I collagen has superior biophysical and biological properties in terms of viscoelasticity, fibrillogenesis, and cell proliferation, and can be used in further studies toward novel potential applications in the field of medical materials.     

Highly Efficient One‐Pot Three‐Component Synthesis and Antimicrobial Activity of 2‐Amino‐4H‐chromene Derivatives

A remarkably efficient three‐component reaction to synthesize 2‐amino‐4H‐chromenes derivatives from malononitrile, various aromatic aldehydes, and orcinol was described at room temperature in CH₂Cl₂ in the presence of catalytic amount of triethylamine. In a facile one‐pot procedure, excellent yields of products were achieved in less than 1 h. Some of the synthesized 2‐amino‐4H‐chromenes derivatives demonstrated potent antibacterial activities against Gram‐positive bacteria including Staphylococcus aureus and Bacillus anthracis, indicated by disk method, minimum inhibitory concentration, and minimum bactericidal concentration approaches. However, none of the tested compounds expressed any antibacterial activities against Enterococcus faecalis and Gram‐negative bacteria.     

A Synergistic Effect of Phthalimide-Substituted Sulfanyl Porphyrazines and Carbon Nanotubes to Improve the Electrocatalytic Detection of Hydrogen Peroxide

A sulfanyl porphyrazine derivative with peripheral phthalimide moieties was metallated with cobalt(II) and iron(II) metal ions. The purity of the macrocycles was confirmed by HPLC, and subsequently, compounds were characterized using various analytical methods (ES-TOF, MALDI-TOF, UV–VIS, and NMR spectroscopy). To obtain hybrid electroactive electrode materials, novel porphyrazines were combined with multiwalled carbon nanotubes. The electrocatalytic effect derived from cobalt(II) and iron(II) cations was evaluated. As a result, a significant decrease in the overpotential was observed compared with that obtained with bare glassy carbon (GC) or glassy carbon electrode/carbon nanotubes (GC/MWCNTs), which allowed for sensitive determination of hydrogen peroxide in neutral conditions (pH 7.4). The prepared sensor enables a linear response to H₂O₂ concentrations of 1–90 µM. A low detection limit of 0.18 μM and a high sensitivity of 640 μA mM⁻¹ cm⁻² were obtained. These results indicate that the obtained sensors could potentially be applied in biomedical and environmental fields.     

Synthesis of Novel Phthalazino[1,2‐b]quinazolinedione Derivatives: Efficient and Practical Reaction of 2‐Amino‐N′‐Arylbenzohydrazides and 2‐Formylbenzoic Acids

This work reported the synthesis of novel phthalazino[1,2‐b]quinazolinedione derivatives through the reaction of 2‐amino‐N′‐arylbenzohydrazides and 2‐formylbenzoic acids in the presence of TsOH in EtOH under reflux conditions.     

Radiolabeling of zoledronic acid with <Superscript>188</Superscript>Re as a new palliative agent radiotracer in treatment of bone tumors

Zoledronic acid is a bisphosphonates to treat bone problems. Rhenium-188-zoledronic acid could be used as a palliate agent in skeletal metastases. Radiolabeled product was prepared through optimized radiochemical procedures. The organs uptake especially bone uptake assessed in healthy animals mice. The radiochemical purity of the radiotracer was > 95% which was stable up to 24 h. Bone uptake (1.08?±?0.14% ID/g at 1 h) with retention of activity in bone up to 24 h (0.26?±?0.06% ID/g) was reached. This radiotracer can be used as a developing candidate for a palliative treatment of bone metastasis.     

A Novel Debromination of vic-Dibromides to Alkenes with InCl3（cat.）／Sm System in Aqueous Media

A novel debromination of vic-dibromides to alkenes with InCl3(cat.)/Sm system in aqueous media has been developed. The reaction gives the E-isomers with excellent yields.     

2-羟基-1-萘甲醛缩邻苯二胺席夫碱及其铜(Ⅱ)配合物的合成及组成测定——介绍一个大学化学综合实验

设计开发了一个大学化学综合性实验,合成了2-羟基-1-萘甲醛缩邻苯二胺席夫碱及其铜(Ⅱ)配合物,分别采用化学分析法和仪器分析法对配合物的组成进行了测定,并结合红外光谱、核磁共振氢谱对产物的结构进行了表征,取得了满意的实验结果。该实验一定程度上弥补了大学化学教学实验中合成有机金属配位化合物教学资源的匮乏。通过该实验的实施,可使学生进一步巩固回流、纯化、离心等基本操作技能,掌握摩尔比法测定配合物配位数及稳定常数的原理和方法,同时掌握运用有机波谱技术推断和鉴定分子结构的方法。本实验有利于培养学生综合运用有机化学、无机化学、化学分析及仪器分析等知识解决具体问题的能力,同时有利于学生了解席夫碱及其金属配合物的性质、研究动态等,激发学生对科学研究的热情,培养学生系统的科学思维和研究能力。