Enhancement of the Antitumour Activity for the Synthesised Dodecylcysteine Surfactant using Gold Nanoparticles

In this paper, the surfactant dodecylcysteine hydrochloride was synthesised. The surface parameters of the synthesised surfactant were studied using a surface tension technique. The surface parameters show a good surface activity of the prepared surfactant in aqueous solution. The self-assembling behaviour of the synthesised surfactant comparing with that of cysteine compound on the prepared gold nanoparticles was confirmed using transmission electron microscope (TEM) measurements. The effect of self-assembling of this surfactant on the size of gold nanoparticles was studied using TEM images. The antitumour activity of the prepared surfactant without and with the gold nanoparticles was investigated. The results show that the antitumour activity of the prepared surfactant was enhanced with the presences of the gold nanoparticles.

Crinumin,a chymotrypsin-like but glycosylated serine protease from Crinum asiaticum: Purification and physicochemical characterisation

Plant latex could be a potential source of novel proteases usable in the food and feed industries because of broad substrate specificity with high stability in extreme conditions. Crinumin, a glycosylated serine protease with chymotrypsin-like activity was purified from the latex of Crinumasiaticum using cation-exchange column chromatography. Crinumin shows activity over a wide range of pH (4.5–11.5 and optimum at 8.5), temperature (75 °C and optimum at 70 °C) and is also functional against chaotrophs, organic solvents, and detergents, even after prolonged exposure. The molecular mass (67.7 kDa), extinction coefficient (17.7), isoelectric point (6.9), and numbers of tryptophan (13), tyrosine (24) and cysteine (15 with 7 disulphide bridges) residues were estimated. K_m of the enzyme was 31.7 μM with casein and 5 × 10⁴ μM with N-succinyl-l-phenylalanine-p-nitroanilide. Easy availability of the aqueous latex, simple purification procedure, high yield (33%), stability and activity in adverse conditions makes it applicable for the pharmaceutical and food industries.     

3-氨基-2-吡咯甲酸乙酯盐酸盐的合成工艺改进

改进了3-氨基-2-吡咯甲酸乙酯盐酸盐的合成工艺,经过4步反应合成了目标化合物,包括在氢化钠催化下甲酸乙酯和乙腈缩合后再与氨基丙二酸二乙酯缩合,然后经乙醇钠关环及与氯化氢成盐得到;应用氢核磁共振及元素分析对样品结构进行了表征;对各步反应的条件进行改进,结果表明：原料的最优比例是n (HCOOC2H5) ∶n (CH3CN)∶n (NaH)∶n [NH2CH(COOC2H5)2HCl]＝1∶1.2∶1.3∶0.5,反应温度为20℃,反应时间分别为24 h和48 h;在工艺改进的情况下,反应收率得到较大提高,生产成本降低,适合工业化生产。     

Preparation of ZnFe2O4–chitosan-doxorubicin hydrochloride nanoparticles and investigation of their hyperthermic heat-generating characteristics

In this study, the structural morphology and magnetic effects of magnetic ZnFe₂O₄ nanoparticles loaded with the cancer-fighting drug doxorubicin hydrochloride (DOX-HCl) were investigated. These nanoparticles have been found to have potential biomedical applications in targeted drug-delivery systems. The zinc ferrite nanoparticles were prepared by a chemical coprecipitation method and coated with chitosan. The nanoparticles were loaded with DOX-HCl and their surfaces improved by folic acid, which can be activated to target specific cancer cells. The specific absorption rate (SAR) values of the ZnFe₂O₄–chitosan–DOX-HCl nanoparticles were investigated at a frequency of 200 kHz and 1.5 kA/m amplitude in order to obtain Brownian relaxation time parameters. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), vibrating sample magnetometry (VSM), and ultraviolet–visible spectrophotometry (UV–vis) were used to characterize the bulk properties of these nanoparticles. In addition, the impact of the nanoparticles under an alternating current (AC) magnetic field and their heat-generation ability were investigated using an experimental setup. The average nanoparticle size was found to be 8.5 nm. Magnetic hysteresis loops confirmed the superparamagnetism of the nanoparticles. The saturation magnetization was 6 emu/g. UV–vis was used to measure the amount of drug loaded onto the nanoparticles. The amount of drug absorption was significantly higher after 12 h, totaling 75%. The specific absorption rate parameter was 80.66 W/g, and the Brownian relaxation time was 188×10⁻⁹ s.     

Formulation,characterization and clinical evaluation of propranolol hydrochloride gel for transdermal treatment of superficial infantile hemangioma

The objective of the present study is to formulate and characterize propranolol hydrochloride (PPL?·?HCl) gel, and to evaluate the efficacy of this formulation in transdermal treatment for superficial infantile hemangioma (IH). The transdermal PPL?·?HCl gel was prepared by a direct swelling method, which chose hydroxypropyl methylcellulose (HPMC) as the matrix and used terpenes plus alcohols as permeation enhancer. Permeation studies of PPL?·?HCl were carried out with modified Franz diffusion cells through piglet skin. Our results pointed to that among all studied permeation enhancers, farnesol plus isopropanol was the most effective combination (Q_24, 6027.4?±?563.1?μg/cm², ER, 6.8), which was significantly higher than that of control gel (p?相似文献   

废盐酸浸出菱锰矿制备四水氯化锰扩大试验

对用工业废盐酸浸出菱锰矿制备四水氯化锰进行了扩大试验。结果表明:在浸出温度80℃、pH=3.0、液固体积质量比4∶1、浸出时间60min条件下,锰浸出率达91.1%;浸出过程中添加硫酸锰可去除大部分钙,浸出液一次浓缩后,除钙率达到95%;利用氟化锰除镁,氟化锰过量系数为1.0时,除镁率达86%;净化液经氯化钡脱硫、浓缩结晶,获得四水氯化锰产品,其质量达到HG-T3816—2006标准,锰回收率为72.3%。     

环（D-天冬氨-D-脯）二肽的合成

以D-天冬氨酸和D-脯氨酸为原料,先合成N-叔丁氧羰基-D-天冬氨酸-β-苄酯和D-脯氨酸甲酯盐酸盐,然后经DCC缩合得直链二肽,再经Pd/C催化氢解,HCl/Et2O脱Boc保护,最后弱碱性条件下成环得环（D-天冬氨-D-脯）二肽,结构经ESI-MS、IR、^1HNMR、^13CNMR等表征。     

头孢母核7-ACT盐酸盐的合成工艺改进

以7-ACA为原料,在三氟化硼催化下,与1-甲基-5-巯基四氮唑发生缩合反应,制备头孢母核7-ACT盐酸盐。反应完毕以浓盐酸析晶得到目标化合物。经熔点测定及1H-NMR分析确证目标产物结构,HPLC的质量分数为98%~99%,收率>90%。     

微波结合盐酸羟铵诱变选育高产醋酸菌

以醋酸菌AFA-01为出发菌株,首先利用微波诱变菌株,之后再采用盐酸羟铵点式平板法处理,获得产酸性能较好的突变株AFA-WH3,其产酸量为7.35g/100mL,较出发菌株提高了43.55％,乙醇脱氢酶(ADH)活力达2786U/mL,较出发菌株提高94.83％.该菌株经8次传代,产酸稳定,可进行下一步的研究.