Spectrophotometric investigation of the chemical compatibility of the anticancer drugs irinotecan-HCl and epirubicin-HCl in the same infusion solution

The use of infusional chemotherapy, especially in an ambulatory setting, absolutely requires that the individual agents remain stable in solution at room temperature and that the drugs be compatible. Because of this, investigation of the chemical compatibilities of chemotherapeutic drug combinations given in the same infusion solution is quite important especially if the drugs are to remain in solution for long periods. Thus, the visual and chemical compatibility of irinotecan and epirubicin in the same infusion solution were investigated using both reference standards and pharmaceutical dosage forms. No sign of incompatibility was observed upon visual examination by means of effervescence, pH change, precipitation and colour change. But a chemical incompatibility was observed using a spectrophotometric method in the spectra of irinotecan-HCl and epirubicin-HCl. The molar ratio of epirubicin-HCl/irinotecan-HCl at which the interaction reached a maximum was found to be 2:1. The chemical interaction occurred immediately after admixing and no visual or spectral change was noticed for 24 h after the interaction had occurred. It is concluded that these drugs are chemically incompatible. While the applicability of these two drugs in combination is investigated in further pharmacological studies, their chemical interaction should also be a consideration. The positive or negative contribution of this interaction to the pharmacological effect of the combination might be of importance, and therefore should be investigated in further clinical trials.     

Objective scar assessment—A new method using standardized digital imaging and spectral modelling

Introduction

Quantitative assessment of scars is needed in clinical practice and in scientific studies. To date, there have been no entirely objective methods available for these purposes. We introduce a new method developed for scar assessment combining standardized digital imaging (SDI) and spectral modelling (SpM). With this method, the estimated concentration changes (ECCs) of haemoglobin and melanin in the scar can be determined quantitatively.

Patient and methods

: In the current study, 22 skin graft donor site (SGDS) wounds were treated with two alternative dressing materials, Suprathel^® and Mepilex Transfer^®, side by side on the same wound. The SGSD scars were assessed using SDI and SpM. The scars were given subjective ratings by three surgeons using the POSAS and the Vancouver Scar Scale (VSS). The correlations between the ECCs of melanin and haemoglobin and the corresponding subjective ratings were calculated as well as the Intraclass Correlation Coefficient (ICC) of the subjective ratings.

Results

There was a statistically significant correlation between the ECCs of melanin and haemoglobin and the subjective ratings. A single observer could reliably assess pigmentation with the POSAS scale (ICC = 0.75) but not vascularity (ICC = 0.51). The reliability ratings of the VSS were unacceptably low.

Conclusions

The ECC values of haemoglobin and melanin give accurate documentation of the scar status. The results also show that the subjective ratings in this study were unreliable especially when interfering pigmentation and increased vascularity were both present at the same time.     

Derivatization of thiols under flow conditions using two commercially available propiolate esters

In the present study we report new data on the reaction of three representative thiols – captopril (CAP), cysteine (CYS) and N-acetylcysteine (NAC) – with two commercially available propiolate esters – methyl-propiolate (MP) and butyl-propiolate (BP) – under flow conditions. The reactions were investigated on-line using sequential injection analysis (SI) and the formed derivatives were monitored spectrophotometrically at 285 nm. The effect of critical parameters of the reaction such as the pH, the temperature and the amount concentration of the reagents were studied in detail including stopped-flow (SF) experiments. Both reagents were found to be suitable for the automated derivatization of thiols, although MP offered faster kinetics compared to BP. The applicability of the procedures was demonstrated by the development of SI methods for the dissolution studies of CAP tablets with satisfactory results.     

罗红霉素与1,2,5,8-四羟基蒽醌的荷移反应研究

目的 通过罗红霉素与1,2,5,8-四羟基蒽醌的荷移反应来快速测定罗红霉素片剂中罗红霉素的含量.方法 利用分光光度法通过分光光度计测定制剂中有效成分的含量.结果 罗红霉素与1,2,5,8-四羟基蒽醌在乙醇-丙酮介质中发生电荷转移反应,生成物颜色发生变化,产物最大吸收波长为570nm,表观摩尔吸光系数为2.56×10~3L/(mol·cm),稳定常数为6.59×10~5,荷移络合物的组成比为1:2,相对标准偏差为1.08%(n=8),药物浓度在30-210mg/L范围内呈线性关系,回收率符合要求.结论 此方法简便易行,便于操作,条件易于控制,可应用于实际工作中.     

Microextraction technique based on ionic liquid for preconcentration and determination of palladium in food additive,sea water,tea and biological samples

Modified cold-induced aggregation microextraction (M-CIAME) is a fast and simple method for extraction and preconcentration of metal ions from samples with high salt content. Furthermore, this technique is much safer in comparison with the organic solvent extraction. The extraction of palladium (Pd) was performed in the presence of Michler thioketone (TMK) as the complexing agent. In this method, sodium hexafluorophosphate (NaPF₆) was added to the sample solution containing small amounts of 1-hexyl-3-methylimidazolium tetrafluoroborate [Hmim][BF₄]. Afterwards, the solution was placed in the ice bath and a cloudy solution was formed. After centrifuging, the extraction phase was settled. Under the optimum conditions, the limit of detection (LOD) was 0.2 ng mL⁻¹. The relative standard deviation (RSD) was 1.7% for 40 ng mL⁻¹ of palladium (n = 5).     

尿碘的低砷量砷铈催化分光光度测定方法

目的 改进现行的尿中碘砷铈催化分光光度测定标准方法,减少含砷剧毒试剂的用量以减少环境污染,并使新方法仍具有良好的测定精密度和准确度.方法 将尿碘测定现行标准法检测每份样品的亚砷酸溶液用量由0.100 mol/L(其中含氯化钠25异/L)、2.5 ml改变为0.025 mol/L(其中含氯化钠40 g/L)、2.5 nd;硫酸铈铵溶液用量由O.076 mol/L、0.30 ml改变为0.025 mol/L、0.30 ml;吸光度(A)测定波长由420 nm改为400 nm.实验此新方法的标准曲线线性关系及线性范围、样品测定检测限、精密度、准确度,与现行标准法比较尿碘测定结果及测定过程的A值变化速率;并实验此新方法在20～35℃范围内砷铈反应温度与反应时间的适宜组合.结果 改进后的新方法砷铈反应在20～35℃范围内选择任一稳定的温度及固定的反应时间都有碘质量浓度(C)与测定A值定量关系C=a+blgA,标准曲线线性范围为0～300μg/L(r=-0.9998),最低检测限为4μg/L(取样量为0.25 ml);精密度:测定尿碘为66.0、76.0、147.5、265.5μg/L时,变异系数(CV)分别为1.7%(1.1/66.0)、1.8%(1.4/76.0)、2.0%(3.0/147.5)、1.6%(4.2/265.5);准确度:对低、中、高含碘最4份尿样加碘标平均回收率分别为101.0%(40.4/40.0)、100.4%(100.4/100.0)、100.5%(60.3/60.0)、100.4%(100.4/100.0),总平均回收率为100.6%,回收率范围为95.0%(57.0/60.0)～103.7%(62.2/60.0);分别在20、25、30、35℃反应温度下测定低、高两种尿碘标准物质,其结果均在给定值的不确定度范围内,且相对偏差分别<5.0%和<2.0%;与现行标准法同时测定48份尿样,二者比较差异无统计学意义(t=0.634,P>0.05).新方法的反应温度与时间适宜组合系列数据为20℃和53 min、25 ℃和40 min、30 ℃和30 min等.与标准法比较,新方法砷铈反应的铈A值变化更加缓慢,进一步减少了测定过程温度波动或测定时间操作偏差所引起的测定误差.结论 改进后的新方法比现行标准方法大大减少了废液含砷量,减少了环境污染、节省了试剂,简便易操作,并提高了尿碘测定精密度和准确度,适合推广应用.

Abstract：

Objective To improve the current standard method of measuring urinary iodine by As (Ⅲ)-Ce4+catalytic spectrophotometry, reducing the amount of arsenic toxic reagent used to decrease environmental pollution,and make the modified method with good precision and accuracy. Methods For improving the current standard method of measuring urinary iodine, amount of arsenious acid solution was reduced from 0.100 mol/L H3AsO3(which contains NaCl 25 g/L) 2.5 ml to 0.025 mol/L H3AsO3(which contains NaCl 40 g/L) 2.5 ml;amount of ceric ammonium sulfate solution was reduced from 0.076 mol/L 0.30 ml to 0.025 mol/L 0.30 ml;photometric wavelength was changed from 420 nm to 400 nm. The new modified method was evaluated by standard curve linearity and linear range, sample detection limit, precision, accuracy, and urinary iodine values, and the rates of absorbance change in the test process were compared with the current standard method. Results The calibration relation of C= a + blgA (C: iodine concentration, A : measuring absorbance) in the new modified method existed when As3+-Ce4+ catalytic reaction was kept at a certain stable temperature range between 20 - 35 ℃ and in certain stable reacting time. The linear range of the calibration curve was 0 - 300 μg/L and the linear correlative coefficient was - 0.9998. The detection limit for iodine was 4 μg/L(0.25 ml of urine was tested). The test coefficient of variations(CV) were 1.7%(1.1/66.0), 1.8%(1.4/76.0), 2.0%(3.0/147.5), 1.6%(4.2/265.5) when measuring urine samples with iodine concentration of 66.0, 76.0, 147.5, 265.5 μg/L, respectively. The average recovery was 100.6% with a range of 95.0% (57.0/60.0) - 103.7% (62.2/60.0) when measuring 4 urine samples containing different iodine concentration, and average recovery was 101.0% (40.4/40.0), 100.4% (100.4/I00.0), 100.5% (60.3/60.0),100.4% (100.4/100.0), respectively. The test results of two national standard urinary iodine were all within the given value range and the relative deviation(RD) was < 5.0% and < 2.0% in 20, 25, 30, 35 ℃ test temperature,respectively. No significant difference was found between the results of the 48 urine samples determined by the new modified method and the current standard method(t = 0.634, P > 0.05). The table of suitable combination of As3+-Ce4+ reaction temperature and time for this method was obtained(such as 20 ℃ and 53 min, 25 ℃ and 40 min, 30 ℃and 30 min, etc. ). Compared with the standard method, the rates of absorbanee change of As ( Ⅲ )-Ce4+ reaction in the new modified method were more slowly, which further reducing the determination deviation caused by the temperature fluctuations or measuring time deviation in measurement process. Conclusions This new modified method greatly reduces the amount of arsenic in waste, reduces pollution, saving reagents, and this method is easier to operate with better precision and accuracy, which is suitable for application of measuring iodine in urine.     

碱灰化法和氯酸消化法测定人乳汁含碘量的对比研究

目的 以碱灰化法作金标准,探讨氯酸消化法测定人乳汁含碘量的准确性.方法 收集天津市河西区新鲜人乳汁样品61份,分别应用2008年发布的<食物中碘的测定砷铈催化分光光度法>中的碱灰化法和1999年发布的<尿碘的砷铈催化分光光度测定方法>中的氯酸消化法测定其含碘量.结果 采用两种检测方法得到61对人乳汁含碘量数据,两种方法的测定结果呈高度正相关(r=0.960,t=26.3,P

Abstract：

Objective Take alkaline ashing method as golden standard to explore the accuracy of chloric acid digestion method in determination of human milk iodine. Methods Sixty one breast milk samples collected in Hexi district of Tianjin was measured by the method for determination of iodine in foodstuff by As3+-Ce4+ catalytic spectrophotometry (referred to as the alkaline ashing method) published in 2008 and the method for determination of iodine in urine by As3+-Ce4+ catalytic spectrophotometry(referred to as acid digestion) published in 1999, respectively. were highly correlated(r = 0.960, t = 26.3, P < 0.01), and the regression equation was (Y) = - 28.1 + 0.808X, in which X was independent variable, that is the results of alkaline ashing method; (Y) was dependent variable, that is the estimated data of chloric acid digestion method. The average difference of the results measured by the two methods was 68.3 μg/L, and the results from chloric acid digestion was 38.9% which lower than that of alkaline samples were diluted by 3,4 and 5-fold and then digested by chloric acid, the liquid clarification rates were 80.3% ashing and chloric acid digestion method were, respectively, 165.4, 110.0 μg/L. Conclusions Compared with alkaline ashing method, the results determined by chloric acid digestion method are significantly lower. It is suggested that there are systemic errors in chloric acid digestion method, which means that alkaline ashing method can not be replaced by the chloric acid digestion method.     

滇桂艾纳香紫外-可见光谱鉴别的研究

[目的]为滇桂艾纳香的鉴别研究提供科学依据。[方法]采用紫外-可见光谱法对滇桂艾纳香进行鉴别研究。[结果]滇桂艾纳香紫外-可见吸收光谱图在300 nm和330 nm处的吸收峰较强,且波动范围不大,可作为其光谱鉴别特征。[结论]紫外-可见光谱法可为滇桂艾纳香的鉴别方法提供辅助手段。     

分光光度法测定杜仲雄花中总黄酮的含量

目的:建立杜仲雄花中总黄酮的含量测定方法.方法:采用可见分光光度法,选用测定波长500 nm,以芦丁为对照品.结果:芦丁在7.6～38 g/L范围内线性关系良好,r=0.996 1.样品液Al3+络合后1 h内稳定,平均加样回收率为101.15%,RSD为1.87%,符合要求.结论:该方法操作简便,灵敏度高,重复性好,...