The increasing importance of endothelium-derived relaxing factor(EDRF),which has now been identified as nitric oxide (NO),has been underscored by the eltlcidation of its role'in a growing number of normal and path...The increasing importance of endothelium-derived relaxing factor(EDRF),which has now been identified as nitric oxide (NO),has been underscored by the eltlcidation of its role'in a growing number of normal and pathophysiological processes. Therefore techniques for detection of nitric oxide should serve as useful tools in defining the role of nitric oxide to these processes.We have improved a simple, sensitive assay methods for determination of nitric oxide in blood, tissue, and other body fluids both by fluorometric and by ultraviolet-visible spectrophotometric measurements. Data obtained by floores cence and by UV-visible assay were correlated well (r=0. 9938, P<0. 0001 ).Linearity:0.1￣ 100μmol/L,r =0.9996,P<0.0001. The minimum detection limit were < 10pmol/L. Within-and between-run CVs were 2. 48%and 4. 62% (n = 10),respectively.Reference values for healthy adults(n=40) were(9.82 ± 1. 57) pmol/L. In conclusion:the methods is sensitive, specific,and precise. It is fairly rapid and simple to perform andrequires no pretreatment of sample, i. e., plasma and urine.The value can be obtained by fluorimeter and/or UV-visible spectrophotometer.The present method is sufficiently rapid and simple to make this a practical choice for many laboratories.展开更多
为建立一种脱色评价的方法,以样品吸光度曲线的曲线下面积(area under the curve,AUC)作为脱色率计算依据,将AUC应用于枸杞多糖的脱色工艺考察中,探究枸杞多糖的最佳脱色工艺条件。采用紫外-可见分光光度计,在200~760 nm处对3种色素(原...为建立一种脱色评价的方法,以样品吸光度曲线的曲线下面积(area under the curve,AUC)作为脱色率计算依据,将AUC应用于枸杞多糖的脱色工艺考察中,探究枸杞多糖的最佳脱色工艺条件。采用紫外-可见分光光度计,在200~760 nm处对3种色素(原花青素、叶绿素铜钠、β-胡萝卜素)的溶液分别进行全波长扫描,采用Origin软件统计脱色前后样品液的AUC,用于计算脱色率。将AUC脱色计算方式引入到枸杞多糖的脱色工艺考察,筛选不同类型大孔树脂的脱色效果,并通过单因素与正交试验确定最佳脱色条件。结果表明:上述3种色素分别在0.98~31.25、3.92~125.00、0.39~12.50μg/mL范围内线性关系良好,R2≥0.998 6,平均加标回收率分别为101.86%、100.08%、100.68%,相对标准偏差(relative standard deviation,RSD)分别为2.66%、2.27%、2.55%。采用AUC脱色率计算方法,枸杞多糖粗品采用S8大孔树脂脱色,最佳脱色工艺条件为每100 mg多糖粗品使用S8树脂量为7.5 g、粗品浓度为3.0 g/L、在35℃下脱色时间为60 min。在该脱色工艺条件下,脱色率的平均值为73.01%,RSD为1.01%,说明稳定性良好。展开更多
The characterization of these molecularly imprinted polymers is essential to understanding their binding dynamics and structural properties. Through the analysis of the current research, it is found that there are ove...The characterization of these molecularly imprinted polymers is essential to understanding their binding dynamics and structural properties. Through the analysis of the current research, it is found that there are overlaps in the methods used by scholars. The Langmuir equation is frequently applied to model the adsorption isotherms of MIPs, providing critical insight into the capacity and affinity of the binding sites. Infrared Spectroscopy (IR) plays a crucial role in identifying the functional groups involved in the imprinting process and confirming the successful formation of specific binding sites. UV-visible spectrophotometry is employed to monitor the absorption characteristics of the polymers, offering data on the interactions between the template molecules and the polymer matrix. Transmission Electron Microscopy (TEM) provides detailed visualization of the internal structure of MIPs at the nanoscale, revealing the morphology and size of the imprinted cavities. Thermogravimetric Analysis (TGA) assesses the thermal stability and composition of the polymers, identifying decomposition patterns that are indicative of the material’s robustness under different conditions. Finally, the Laser Particle Size Analyzer is used to measure the size distribution of the polymer particles, which is critical for determining the uniformity and efficiency of the imprinting process. The six characterization methods discussed in this paper provide a comprehensive understanding of MIP, and it is hoped that in the future, more optimized design solutions will emerge and their applications in various fields will be enhanced.展开更多
文摘The increasing importance of endothelium-derived relaxing factor(EDRF),which has now been identified as nitric oxide (NO),has been underscored by the eltlcidation of its role'in a growing number of normal and pathophysiological processes. Therefore techniques for detection of nitric oxide should serve as useful tools in defining the role of nitric oxide to these processes.We have improved a simple, sensitive assay methods for determination of nitric oxide in blood, tissue, and other body fluids both by fluorometric and by ultraviolet-visible spectrophotometric measurements. Data obtained by floores cence and by UV-visible assay were correlated well (r=0. 9938, P<0. 0001 ).Linearity:0.1￣ 100μmol/L,r =0.9996,P<0.0001. The minimum detection limit were < 10pmol/L. Within-and between-run CVs were 2. 48%and 4. 62% (n = 10),respectively.Reference values for healthy adults(n=40) were(9.82 ± 1. 57) pmol/L. In conclusion:the methods is sensitive, specific,and precise. It is fairly rapid and simple to perform andrequires no pretreatment of sample, i. e., plasma and urine.The value can be obtained by fluorimeter and/or UV-visible spectrophotometer.The present method is sufficiently rapid and simple to make this a practical choice for many laboratories.
文摘为建立一种脱色评价的方法,以样品吸光度曲线的曲线下面积(area under the curve,AUC)作为脱色率计算依据,将AUC应用于枸杞多糖的脱色工艺考察中,探究枸杞多糖的最佳脱色工艺条件。采用紫外-可见分光光度计,在200~760 nm处对3种色素(原花青素、叶绿素铜钠、β-胡萝卜素)的溶液分别进行全波长扫描,采用Origin软件统计脱色前后样品液的AUC,用于计算脱色率。将AUC脱色计算方式引入到枸杞多糖的脱色工艺考察,筛选不同类型大孔树脂的脱色效果,并通过单因素与正交试验确定最佳脱色条件。结果表明:上述3种色素分别在0.98~31.25、3.92~125.00、0.39~12.50μg/mL范围内线性关系良好,R2≥0.998 6,平均加标回收率分别为101.86%、100.08%、100.68%,相对标准偏差(relative standard deviation,RSD)分别为2.66%、2.27%、2.55%。采用AUC脱色率计算方法,枸杞多糖粗品采用S8大孔树脂脱色,最佳脱色工艺条件为每100 mg多糖粗品使用S8树脂量为7.5 g、粗品浓度为3.0 g/L、在35℃下脱色时间为60 min。在该脱色工艺条件下,脱色率的平均值为73.01%,RSD为1.01%,说明稳定性良好。
文摘The characterization of these molecularly imprinted polymers is essential to understanding their binding dynamics and structural properties. Through the analysis of the current research, it is found that there are overlaps in the methods used by scholars. The Langmuir equation is frequently applied to model the adsorption isotherms of MIPs, providing critical insight into the capacity and affinity of the binding sites. Infrared Spectroscopy (IR) plays a crucial role in identifying the functional groups involved in the imprinting process and confirming the successful formation of specific binding sites. UV-visible spectrophotometry is employed to monitor the absorption characteristics of the polymers, offering data on the interactions between the template molecules and the polymer matrix. Transmission Electron Microscopy (TEM) provides detailed visualization of the internal structure of MIPs at the nanoscale, revealing the morphology and size of the imprinted cavities. Thermogravimetric Analysis (TGA) assesses the thermal stability and composition of the polymers, identifying decomposition patterns that are indicative of the material’s robustness under different conditions. Finally, the Laser Particle Size Analyzer is used to measure the size distribution of the polymer particles, which is critical for determining the uniformity and efficiency of the imprinting process. The six characterization methods discussed in this paper provide a comprehensive understanding of MIP, and it is hoped that in the future, more optimized design solutions will emerge and their applications in various fields will be enhanced.
