铜铁试剂萃取流动注射-氢化物发生原子吸收光谱法测定纯铜中微量锡

建立了铜铁试剂萃取流动注射-氢化物发生原子吸收光谱法测定纯铜中微量锡的方法。利用铜铁试剂萃取实现了铜与锡的有效分离,样品液中锡与NaBH4生成氢化物,而后经由密闭的流动系统传送至原子化器中,采用原子吸收光谱法加以检测。试验了铜铁试剂的最佳萃取条件,选择锡的测定波长为286.3 nm。该方法的检出限为0.25 ng/mL,测定锡的线性范围为l.0~13.0 ng/mL。方法应用于铜有证参考样品中锡的测定,结果与认定值基本相符,加标回收率为90.0%~97.0%,相对标准偏差为3.2%。     

铜试剂分离法测定煮糖罐积垢中的钙镁含量

EDTA滴定法是测定钙、镁含量的经典方法之一，但由于积垢成分比较复杂，在测定煮糖罐积垢中的钙、镁离子时，产生指示剂封闭现象，使用常规掩蔽剂不能解决此问题。在pH为3左右的酸性溶液中，用六次甲基四胺和铜试剂能够较好地分离出干扰离子。与原子吸收法相比，其测定结果比较准确，且操作简单。     

偶氮胂Ⅲ光度法测定铝合金中微量钪

在pH 1.8的HCl-KCl缓冲溶液中,钪与偶氮胂Ⅲ形成稳定的紫红色络合物,其最大吸收峰在680 nm处。研究了酸度、偶氮胂Ⅲ用量、反应时间、共存元素等因素对显色反应的影响。结果表明:酸度和偶氮胂Ⅲ用量对体系吸光度影响较大,最佳pH值和偶氮胂Ⅲ体积范围分别为1.5~2.0和1.5~2.5 mL;温度对显色反应影响不大,室温下显色5 min即可测定,且吸光度在120 min内基本保持不变;铁、钛、锆严重干扰钪的测定,采用铜铁试剂沉淀分离的方法可消除其影响。在最佳条件下,钪在0~1.0 μg/mL范围内符合比尔定律,表观摩尔吸光系数为1.8×10⁴ L·mol^-1·cm^-1。方法用于铝合金中微量钪的测定,相对标准偏差(RSD)不超过2%,测定结果与标样认定值或对比方法(电感耦合等离子体原子发射光谱法)测定结果基本一致。     

钼-铜铁试剂-醋酸/醋酸钾体系极谱配合吸附催化波机理的研究

钼-铜铁试剂-醋酸/醋酸钾在微分脉冲极谱、常规脉冲极谱和直流极谱上均产生非常灵敏的极谱配合吸附催化波.本研究对这个波的电极过程机理进行了研究.实验结果表明,这个波既具有配合吸附波的性质又具有平行催化波的性质;其突出的特征是,铜铁试剂是Mo(Ⅵ)的配合剂,同时又是平行催化过程中的化学氧化剂,所以,过个波比其他非变价金属-铜铁试剂极谱配合吸附波灵敏得多.测定了钼-铜铁试剂配合物的组成和条件稳定常数.描述了体系的电极还原过程.     

锡—铜铁试剂络合物吸附波研究及其应用

本文发现在0.01％铜铁试剂和0.4mol/L(NH_4)_2SO_4(PH_(5.3))底液中,锡在单扫描示波极谱上有一个良好的络合吸附波。峰电位为-0.66V(VS.SCE)。波高与锡浓度在2×10~(-6)～6×10~(-9)g/ml范围内成正比。实验表明,该波属于络合吸附波。建立了示波极谱法测定河水和铜合金中微量锡的方法。     

Formulation design and optimization of novel soft glycerosomes for enhanced topical delivery of celecoxib and cupferron by Box–Behnken statistical design

Background: The present study describes glycerosomes (vesicles composed of phospholipids, glycerol and water) as a novel drug delivery system for topical application of celecoxib (CLX) and cupferron (CUP) compound.

Aim: The goal of this research was to design topical soft innovative vesicles loaded with CLX or CUP for enhancing the efficacy and avoiding systemic toxicity of CLX and CUP.

Methods: CLX and CUP loaded glycerosomes were prepared by hydrating phospholipid-cholesterol films with glycerol aqueous solutions (20–40%, v/v). Box–Behnken design, using Design-Expert® software, was the optimum choice to statistically optimize formulation variables. Three independent variables were evaluated: phospholipid concentration (X₁), glycerol percent (X₂) and tween 80 concentration (X₃). The glycerosomes particle size (Y₁), encapsulation efficiency percent (Y₂: EE %) and drug release (Y₃) were selected as dependent variables. The anti-inflammatory effect of CLX and CUP glycerosomal gel was evaluated by carrageenan-induced rat paw edema method followed by histopathological studies.

Results: The optimized formulations (CLX2* and CUP1*) showed spherical morphology under transmission electron microscopy, optimum particle size of 195.4?±?3.67?nm, 301.2?±?1.75?nm, high EE of 89.66?±?1.73%, 93.56?±?2.87%, high drug release of 47.08?±?3.37%, 37.60?±?1.89% and high cumulative amount of drug permeated in 8?h of 900.18?±?50.24, 527.99?±?34.90?µg.cm^?2 through hairless rat skin, respectively. They also achieved significant remarkable paw edema inhibition in comparison with the control group (p? Conclusion: Finally, the administration of CLX2* and CUP1* loaded glycerosomal gel onto the skin resulted in marked reduction of edema, congestive capillary and inflammatory cells and this approach may be of value in the treatment of different inflammatory disorders.     

铜铁试剂合成方法的改进

本文介绍了以亚硝酸乙酯代替亚硝酸丁酯，用氯苯代替无水乙醚合成的铜铁试剂的新工艺。该法消除了原工艺中存在的一些弊病，对影响反应的诸因素进行了详细讨论，为该产品的工业化生产提供可靠数据，产品总收率50％左右。