Quantitation of SU1 1248, an oral multi-target tyrosine kinase inhibitor, and its metabolite in monkey tissues by liquid chromatograph with tandem mass spectrometry following semi-automated liquid-liquid extraction

SU11248 is a potent inhibitor of PDGFR, VEGFR, KIT, and Flt3, and is currently under Phase I clinical evaluation as an anticancer drug. A sensitive and specific analytical method for the quantitation of SU11248 and its metabolite in several monkey tissues (liver, kidney, brain and white fat) using LC-MS-MS following semi-automated liquid-liquid extraction (LLE) was developed and validated. Amounts of 50 mg of tissue were homogenized using an ultrasonic processor. After addition of the stable labelled internal standard (IS) and ammonium hydroxide (0.3%), samples were extracted with 2.5 ml of tert-butyl methyl ether. Following centrifugation, aliquots of 1.8 ml of the organic phase were transferred into a 96-well plate. The Packard Multiprobe II robotic liquid handler was used to perform all steps mentioned above. The organic phase was dried and the residue was reconstituted with 800 microl of 15 mM ammonium formate buffer solution (pH 3.25) using a Tomtec Quadra 96 workstation. Aliquots of 10 microl of the resulting solution were injected into the LC-MS-MS system. A Symmetry Shield C8 column (50 mm x 2.1 mm, 3.5 microm) was used to perform the chromatographic analysis. The mobile phase was 15 mM ammonium formate buffer solution (pH 3.25)-acetonitrile (74:26 (v/v)) with a flow-rate of 0.35 ml/min. Retention times of the metabolite and SU11248 were about 2.5 and 3.5 min, respectively. Total cycle time was 5 min. MS detection used the Applied Biosystems-MDS Sciex API 3000 with TurbolonSpray interface and multiple reaction monitoring (MRM) operated in positive ion mode. The method was validated for both compounds over the calibration range of about 2 and 2000 ng/g. The suitability and robustness of the method for in vivo samples were confirmed by analysis of monkey tissues from animals dosed with SU11248.     

An optical surface plasmon resonance biosensor for determination of tetanus toxin

Surface plasmon resonance (SPR) has been successfully applied for the simple, rapid, and label-free assay of various biomolecules. This assay evaluates a novel wavelength modulation SPR biosensor for the detection of tetanus toxin. The wavelength modulation SPR biosensor is designed based on fixing the incident angle of light and measuring the reflected intensities in the resonance wavelength range spanning 400-800 nm simultaneously. Tetanus toxin (TeNT), one of the most potent toxins known, is synthesized as a 150 kDa single polypeptide chain. The SPR biosensor has been shown to be capable of directly detecting concentration of tetanus toxin as low as 0.028 Lf ml⁻¹. Under selected experimental conditions, the SPR biosensor has a good reproducibility, sensitivity and reversibility. The results illustrate how wavelength modulation SPR biosensor can be used to detect biomolecular interactions.     

SciFinder-guided rational design of fluorescent carbon dots for ratiometric monitoring intracellular pH fluctuations under heat shock

Intracellular pH plays a significant role in various biological processes, including cell proliferation, apoptosis, metabolism, enzyme activity and homeostasis. In this work, a novel design strategy for the preparation of pH responsive carbon dots (CDs-pH) for ratiometric intracellular imaging was reported. By using SciFinder database, fluorescent CDs-pH with the required pK_a value of 6.84 were rationally designed, which is vital important for precise sensing of intracellular pH. As a result, the synthesized CDs-pH demonstrated robust ability to test pH fluctuations within the physiological range of 5.4-7.4. The CDs-pH was further utilized for fluorescent ratiometric imaging of pH in living HeLa cells, effectively avoided the influence of autofluorescence from native cellular species. Moreover, real-time monitoring of intracellular pH fluctuation under heat shock was successfully realized. This SciFinder-guided design strategy is simple and flexible, which has a great potential to be used for the development of other types of CDs for various applications.     

Pt/HL和Pt/KL沸石在异丙醇分解反应中的不同催化行为

Ｐｔ／ＫＬ沸石在异丙醇分解反应中具有很高的脱氢活性,而Ｐｔ／ＨＬ沸石具有明显的缺电子性,在此反应中难以显示出脱氢活性,通过加氢作用,可使沸石的酸位免受积炭覆盖,从而可增强Ｐｔ／ＨＬ沸石的酸性催化作用。     

p-CH3C6H4SR型硫醚与钯(II)配合物热分解反应动力学

热重分析(TG)和微商热重法(DTG)广泛应用于各个研究领域,用非等温热重法测定固体化合物的热分解动力学参数已有报导.许多作者提出各种不同的数据处理方法.本文用的ρ-CH_3C_6H_4SR 型硫醚对钯的萃取具有选择性好、分配比高、气味较小、易溶于脂肪烃类溶剂、易于合成、是很有发展前途的一类萃取剂.我们合成五种ρ-CH_3C_6H_4SR(R:n-C_4H_9,n-C_6H_(13),n-C_8H_(17),n-C_(10)H_(21),n-C_(12)H_(25))型硫醚与钯(Ⅱ)的配合物,用TG-DTG 法研究它们的热分解过程,用微商法(Freeman-Carroll 方程)及积分法(Coats-Redfern 方程)获得了这些配合物的热分解动力学参数.     

7种中位—四取代苯基卟啉化合物的合成

卟啉是一类结构与生命物质(如血红素和维生素B_(12))相似的化合物,近年来曾被用于人体肿瘤的光动力学治疗;此外,在电化学、光物理学和光化学、放射医学、微量元素测定、纺织品漂洗等领域中的应用也相当广泛,已受到科技工作者的普遍关注和重视。本文按Rothemond法将相应的取代苯甲醛与新蒸吡咯在丙酸中缩合,制得具有酸性、中性和碱     

硼化合物的研究XX:乙醇胺合三(2-呋喃基)硼烷的合成及其转化

2-呋喃基锂与(N,N-二乙胺基)二氯硼烷的反应是以三烃基化的方式发生,因而可用于制取三(2-呋喃基)硼烷,并可以得到乙醇胺配合物1的稳定形式。乙醇胺合三(2-呋喃基)硼烷(1)可在稀酸中游离出三(2-呋喃基)硼烷,可与吡啶形成吡啶合三(2-呋喃基)硼烷2;化台物1中的呋喃环被8-羟基喹啉或8-羟基喹哪啶裂开以后,分别形成含 B-N 内配键的二呋喃基硼螯合物3及4。化合物1～4均经元素分析及有关波谱鉴定。     

钒、铬、锰磷桥络合物中31P NMR化学位移的研究

ISSIe山和W6flSChllh山子1960年首次用pdCI。和二苯基磷合成出黄色的二聚络合物，后被H。yieY＊确认为具有pRZ的桥式结构．此后一系列该类结构的化合物被合成并引起了广泛的兴趣．磷可以和两个甚至多个金属原子络合构成多核金属络合物，在催化反应中有重要应用．磷原子存在多种电子态，其3d空轨道也能参与成键．P乃1的NMR谱是研究含磷化合物立体结构的有力工具．P－31与其它核素之间的耦合常数以及P－31的化学位移对阐明化合物的立体构象以及电子结构具有重要作用．近年来，West饲用计算机神经网络技术预测P－：if的化学位移，但仅…     

用手性高效液相色谱对β—羟基酯化合物进行对映体分离

本文利用手性ＯＤ柱在高效液相色谱上对光活性β－羟基酯类化合物进行了对映体分离，达到了较好的分离效果，并通过讨论手性ＯＤ涂附物的结构与该类化合物的作用方式，解释了不同的该类化合物的色谱分离效果。     

Elucidating dominant factors of PO43-, Cd2+ and nitrobenzene removal by biochar: A comparative investigation based on distinguishable biochars

Four distinct biochars were employed to remove three typical pollutants, meanwhile, path analysis, a multi-statistical regression method, was performed to elucidate the dominant factors of biochar adsorption. This work can provide a new insight to prepare a targeted biochar as adsorbents.