盐酸曲马多血药浓度测定方法概况

盐酸曲马多（tramadol hydrachloride,TMD）是中枢类镇痛药,镇痛效果好,临床上广泛地应用于中、重度急、慢性疼痛的治疗。本文就近年来有关其血药浓度的测定方法作一综述。     

影响骨髓移植术后环孢素A血药浓度的相关因素分析

目的:环孢素A是临床常用的免疫抑制剂,应用于预防骨髓移植术后发生的移植物抗宿主病。环孢素A药代动力学及药效学个体差异大,治疗窗窄,其血药浓度受多种因素影响。本文研究探讨骨髓移植术后患者环孢素A血药浓度,寻找影响其血药浓度变化的可能因素,并为临床上药物使用提供参考依据。方法:以化学发光微粒子免疫分析法测定并记录骨髓移植术后患者应用环孢素A后的血药浓度,并根据环孢素A血药浓度、患者的基本情况(性别、年龄、手术日期等)、用药情况(剂量、给药方式、合并用药等)及相应生化检验结果等,应用SPSS统计软件对数据进行多元线性回归分析,考察环孢素A血药浓度与各生化指标的相关性。结果:环孢素A的单位血药浓度与患者的性别、年龄及体重无明显的相关性,与血浆CHO、AST、BUN、三唑类抗真菌药物具有统计学意义的相关性(P0.05)。结论:环孢素A的血药浓度不仅受自身个体因素的影响,还与给药方式、合用药物情况等外界因素有关。应结合患者的临床表现进行全面分析,建议定期监测血药浓度,及时调整治疗方案,实现个体化给药,使环孢素A在骨髓移植术后的应用得到最佳的治疗效果。     

岩舒血药浓度检测的实验研究

目的:建立中药复合制剂岩舒的血药浓度检测平台。方法:采用日本日立L-2130高效液相色谱仪对苦参碱标准品进行生理盐水和标准血清的色谱分析以及对输注岩舒患者的血清色谱分析,并在实验前制备标准曲线,完成回收率实验和精密度测定。结果:在所有色谱图上,色谱保留时间以3．61、3．59、3．69、3．63min为共同标识,且实验稳定,可信度高。在实测色谱图上色谱保留时间为3．64±0．05min为岩舒血药浓度的标准值,峰高为岩舒血药浓度的百分含量。结论:本研究将为临床测定岩舒的血药浓度和半衰期建立良好的检测平台。     

HPLC法测定大鼠血浆中EGCG的血药浓度

目的:建立快速、高效、灵敏的HPLC法测定大鼠血浆中的EGCG血药浓度。方法:以睾丸酮为内标物,血浆经盐酸和乙酸乙酯等去除蛋白。采用Agilent 20RBAX SB-C18色谱柱,乙腈-0.3%乙酸为流动相,流速1.0ml/min,检测波长为280nm,柱温40℃。结果:EGCG和内标的出峰时间分别为12.21min和15.4min。EGCG在0.05μg/ml-100μg/ml范围内线性关系良好(R2=0.9920),高、中、低3种浓度下的日内、日间精密度RSD均低于15%,相对回收率与绝对回收率均在100±15(%)范围内,稳定性好。结论:本方法灵敏、准确、高效,适用于大鼠血浆中EGCG的血药浓度检测。     

帕罗西汀血药浓度检测方法研究进展

帕罗西汀为5-羟色胺（5-HT）阻断药,具有起效快、疗效好、不良反应低等优点,为目前临床上常用抗抑郁症药物。帕罗西汀疗效和不良反应与该药血药浓度密切相关,并且个体差异性较大。因此,研究开发专一性强、灵敏度高的血药浓度检测方法十分必要,具有重要的临床和实践意义。本文综述帕罗西汀血药浓度检测时血样的前处理方法,同时对高效液相色谱法和气相色谱法检测帕罗西汀血药浓度进展进行论述,为该领域的临床合理用药和相关领域的研究提供借鉴。     

酶标仪法测定氨茶碱血药浓度的研究

摘要 目的：通过酶标仪法,建立一种研究氨茶碱在新西兰兔体内的药代动力学参数及房室模型的分析方法。方法：新西兰兔以剂量15 mg/kg静脉注射氨茶碱后,应用酶标仪法,测定在274 nm 波长处吸光度值,采用直线相关与回归分析进行数据统计分析氨茶碱在体内的药代动力学参数、回收率实验及房室模型分析。结果：血清茶碱在浓度5～30 μg/mL范围内线性关系良好,回归方程为：A= 0.0013C+0.0074,r²=0.991。各浓度氨茶碱回收率均大于90%,平均回收率为95.83±3.83,RSD均小于15%,回收效果良好。通过氨茶碱体内房室模型拟合得：二室模型拟合显示：由消除相,得外推线浓度线性回归方程：lgC=-0.1271t+1.0562;由分布相,得残数浓度线性回归方程为：lgCr =-0.5829t+1.030,综合得其二室模型的药动学方程为：C=22.000e^-1.342t +11.381e^-0.292t 、T_1/2（α）= 0.516 h、T_1/2（β）= 2.369 h。一室模型拟合显示：一室模型药动学方程为：lgC= -0.2131t + 1.315,其药时方程为：C= 20.649e^-0.491t 、T_1/2= 1.412 h;结论：可以用酶标仪法测定氨茶碱体内药代动力学相关参数,其回收率良好,体内代谢符合二室模型,消除半衰期较长。     

β—环糊精包合荧光法监测蛇床子素的血药浓度

用β-环糊精(β-CD)为包合试剂的荧光法对兔体血浆中蛇床子素的血药浓度进行24h的监测,达峰时间为0.75 h,血中蛇床子素的含量在3.02×10-6～7.26×10-6g/ml之间,方法简便、快速、效果良好.     

不同NaCl浓度对降纤酶效价测定的影响

降纤酶是从长白山白眉蝮蛇或尖吻蝮蛇毒中提取的单一成分蛋白水解酶,属蛇毒类凝血酶。1997年部颁标准采用以纤维蛋白原为底物,0.04mol/LTris-HCl(pH值7.4,含0.02mol/LNaCl)缓冲液溶解稀释纤维蛋白原、降纤酶标准品和供试品,通过测定降纤酶促凝活性来测定其效价[1]。　　在降纤酶生产和质量检验过程中,曾出现冻干成品核检效价比未冻干前半成品效价降低50%左右,严重影响到生产的管理和产品质量控制。为此,我们通过对降纤酶溶液pH值、NaCl浓度和冻干过程中温度、时间的控制等可能影响效价因素进行逐一排查,发现NaCl浓度是影响降纤酶效价…     

高效液相色谱法测定大鼠血浆中来那度胺的浓度及其药动学*龚

摘要目的：建立高效液相色谱法测定大鼠血浆中来那度胺的浓度。方法：色谱柱采用Venusil ASB C18 column (4.6 mm× 250 mm,5 μm) 购自于博纳艾杰尔科技有限公司。样品采用梯度洗脱,流动相为乙腈和0.05%甲酸溶液,流速为1.0 mL/min,检测波长为254 nm,以沙利度胺为内标。结果：来那度胺血药浓度的线性范围为0.1-5 滋g/mL,最低检测限为0.1 μg/mL,三个浓度的QC 样品(0.2, 1 and 5μg/mL)的提取回收率分别为78.8± 3.8, 80.1 ± 3.2 and 79.1 ± 7.6 %。结论：此方法准确、简便、灵敏度高,对来那度胺的血药浓度测定和药物代谢动力学研究极具价值。     

高效液相色谱法同时测定人血浆中洛匹那韦和利托那韦浓度

为建立同时测定人血浆中洛匹那韦和利托那韦浓度的高效液相色谱方法,取血浆样品200μL,以地西泮为内标,叔丁基甲醚液提取,有机相室温下氮气吹干,20%乙腈100μL复溶,振荡离心后取20μL进样分析.结果发现,洛匹那韦在0.5~20mg/L范围内、利托那韦在0.05~5mg/L范围内线性良好(r=0.9995和0.9997).低(1/0.25mg/L)、中(10/2.5mg/L)和高(18/4.5mg/L)3个质量浓度质控样品中,洛匹那韦和利托那韦的日内变异分别为2.16%~3.20%和2.12%~2.60%,日间变异分别为2.34%~4.04%和0.31%~4.94%.方法学回收率为99.88%~106.29%.利托那韦、洛匹那韦和内标(地西泮)的绝对提取率分别为79.17%,52.26%和91.35%.稳定性考察结果良好.结果显示,本方法灵敏度高、经济简便、结果准确可靠,为开展洛匹那韦和利托那韦的人体药代动力学研究提供了方法学基础.     

Inter-sulfhydryl distances in plasma fibronectin determined by fluorescence energy transfer: effect of environmental factors

Human plasma fibronectin, a dimeric glycoprotein, contains two cryptic free sulfhydryl groups per chain. Recent observations revealed that upon binding to a gelatin-coated surface the SH1 site, located between the DNA-binding and cell-binding domains, is partially exposed, while the SH2 site, situated within the carboxyl-terminal fibrin-binding domain, remains buried. Utilizing this newly discovered property of plasma fibronectin, we have developed a procedure to introduce maleimide derivatives of fluorescent probes such as N-(1-pyrenyl)maleimide, 7-(diethylamino)-3-(4'-maleimidylphenyl)-4-methylcoumarin, or fluorescein 5-maleimide selectively into either the SH1 or SH2 site of the fibronectin molecule and have measured the inter-sulfhydryl distances in fibronectin by fluorescence energy transfer methods. The results show that the distance between the SH1 site of one subunit and the SH1 site of the other subunit is between 35 and 44 A, indicating the close proximity of the two subunits near the SH1-containing regions. On the other hand, the distance between the SH2 site of one subunit and the SH2 site of the other subunit is found to be greater than 95 A, suggesting that the two SH2-containing regions are well separated. Additionally, the distance between the SH1 and SH2 sites within each subunit is estimated to be 42-53 A, assuming no intersubunit energy transfer between the probes. Heparin or high salt, which drastically affects the hydrodynamic properties of fibronectin, had virtually no effect on the distance between the SH1-SH1 or the SH1-SH2 pair.(ABSTRACT TRUNCATED AT 250 WORDS)     

Solution structure of human plasma fibronectin as a function of NaCl concentration determined by small-angle X-ray scattering

The structure of human plasma fibronectin in 50 mM Tris-HCl buffer, pH 7.4, containing varying concentrations of NaCl, has been investigated using the small-angle X-ray method.Below 0.3 M NaCl the overall structure of the molecule is disc-shaped; at 0 M NaCl the axial ratio of the disc is about 1:7 and between 0.1 M to 0.3 M it is slightly more asymmetric, with an axial ratio of 1:10.At about 0.3 M NaCl there is a reversible transition to a more open structure, and, from 0.3 M up to 1.1 M NaCl the small-angle X-ray data can be explained by models consisting of ensembles of flexible, non-overlapping, bead-chains generated by a Monte Carlo procedure. Within this concentration range there is a gradual increase in the stiffness of the chains, as well as a decrease in bead radius, which indicates that the molecule becomes more open when the NaCl concentration is increased.The transition to a more open structure is also demonstrated by the average radius of gyration which increases gradually from 8.26 nm at 0 M NaCl to 8.75 nm at physiological or near-physiological conditions, and up to 16.2 nm at 1.1 M NaCl.Abbreviations hpFN human plasma fibronectin - SAXS smallangle X-ray scattering - Tris tris (hydroxymethyl) aminomethane - DTT dithiothreitol - BA benzamidine hydrochloride - PMSF phenylmethylsulfonyl fluoride     

Arginine carboxypeptidase (CPR) in human plasma determined with sandwich ELISA.

There are two types of carboxypeptidases present in human blood, carboxypeptidase N (CPN) and arginine carboxypeptidase (CPR). CPR is generated during coagulation from a precursor (proCPR) which can be converted to the active form by trypsin in vitro. Since it is difficult to distinguish the two types of carboxypeptidases in human blood by the measurement of enzyme activity, we established a quantitative sandwich ELISA by which CPR can be quantitated. The amount of CPR in plasma, fresh serum and heated serum were essentially the same. Therefore the ELISA assay does not distinguish proCPR, activated CPR and inactivated CPR. With the ELISA method, CPR was quantitated in plasma from fifty patients with rheumatoid arthritis and eleven patients with severe hepatitis as well as healthy individuals. The amount of CPR in plasma obtained from patients with rheumatoid arthritis was not found to be lower than that of normal subjects. Furthermore, the patients who suffered severe hepatitis and had very low levels of CPR-total were fatal. This suggests that a decrease of CPR level might be a good indication of a patient's prognosis to death by hepatitis.     

"Antioxidant" (reducing) efficiency of ascorbate in plasma is not affected by concentration

Ascorbate (vitamin C), an important dietary derived antioxidant, reportedly shows decreasing "antioxidant efficiency" with increasing concentrations in indirect radical trapping methods of antioxidant capacity. This study investigated the effect of concentration on antioxidant efficiency of ascorbate using a direct test of antioxidant capacity, the ferric reducing/antioxidant power test (FRAP assay). Results showed that the antioxidant efficiency factor of ascorbate was 2 and was constant over a wide concentration range in both plasma and pure aqueous solution. However, the absolute amount of ascorbate lost per unit of time increased with concentration. Furthermore, ascorbate was less stable in plasma than in aqueous solutions of similar pH and less stable in ethylenediamine tetraacetic acid (EDTA) than in heparinized plasma. Results indicate that previously reported concentration-dependent changes in antioxidant efficiency of ascorbate may have been caused by loss of ascorbate prior to and during testing, and by methodologic characteristics of indirect peroxyl radical trapping tests of antioxidant capacity. Therefore, it is suggested that the premise that the antioxidant efficiency of ascorbate is concentration-dependent is largely methodologically derived and does not reflect the antioxidant behavior of ascorbate per se.