24小时热门版块排行榜

返回列表

当前只显示满足指定条件的回帖，点击这里查看本话题的所有回帖

lcb19700525

铁杆木虫 (正式写手)

应助: 0 (幼儿园)
金币: 7799.8
帖子: 679
在线: 90.6小时
虫号: 369126
注册: 2007-05-12
性别: GG
专业: 药物学

[求助] 求助14C尿素国外质量标准已有1人参与

求助14C尿素国外质量标准

回复此楼

» 猜你喜欢

求助冯连芳、张才亮的《聚合过程强化技术》已经有1人回复
2026考博已经有0人回复
药理学论文润色/翻译怎么收费? 已经有158人回复
浙江中医药大学张勇民院士2026年博士研究生招生已经有3人回复
硫醚氧化已经有2人回复
26博士申请-药物化学方向已经有32人回复
求助cortellis数据库查询针对靶点ABCC6的药物和在研分子已经有1人回复
章慧等编著的《配位化学：原理与应用》已经有1人回复
求助！！！大佬救命！！！已经有4人回复
酰胺缩合已经有3人回复

» 本主题相关价值贴推荐，对您同样有帮助:

求助14C尿素国外质量标准已经有2人回复

1楼 2014-05-15 10:30:43

已阅回复此楼关注TA 给TA发消息送TA红花 TA的回帖

eroitoei

新虫 (正式写手)

应助: 0 (幼儿园)
金币: 88.4
红花: 8
帖子: 462
在线: 19小时
虫号: 3069671
注册: 2014-03-19

美国药典有的，2楼正解

赞一下

回复此楼

4楼2014-05-16 11:10:23

已阅回复此楼关注TA 给TA发消息送TA红花 TA的回帖

查看全部 6 个回答

痴夷子皮

版主 (文坛精英)

老痞

DRDEPI: 8
应助: 2016 (讲师)
贵宾: 5.368
金币: 54487.3
散金: 41688
红花: 303
沙发: 1206
帖子: 32611
在线: 4303.7小时
虫号: 674536
注册: 2008-12-14
性别: GG
专业: 无神论
管辖: 人文社科

【答案】应助回帖

感谢参与，应助指数 +1

没有原料的
Urea C 14 Capsules

» Urea C 14 Capsules contain 14CH4N2O in which a portion of the molecules are labeled with radioactive 14C to provide 0.04 MBq (or 1 µCi) of radioactivity per capsule. It contains not less than 90.0 percent and not more than 110.0 percent of the labeled amount of 14C expressed as MBq (or µCi).
Packaging and storage— Preserve in tight containers, and store at controlled room temperature.
Expiration date— The expiration date is not later than two years from the date of manufacture.
Labeling— Label it to include the following: the amount of 14C, expressed in MBq (or µCi) per Capsule at the time of calibration; the expiration date; the total radioactivity per container; and the statement, “Caution—Radioactive material.”
Radionuclide identification 821— A solution of 1 or more Capsules in 1 N hydrochloric acid when tested using a liquid scintillation counter produces beta emission having a 49 keV mean and a 156 keV max.
Dissolution 711—
Medium: simulated gastric fluid TS; 500 mL.
Apparatus 1: 50 rpm.
Time: 10 minutes.
Procedure— Determine the background levels of 14C with a 1-mL portion of the solution under test using a liquid scintillation counter.
Tolerances: not less than 80% (Q) of the labeled amount of 14C is dissolved in 10 minutes.
Uniformity of dosage units 905: meet the requirements.
Radionuclidic purity 821— Determine the radionuclidic purity of a solution of 1 or more Capsules in water using a liquid scintillation counter: not less than 99.9% of the radioactivity is present as C 14.
Radiochemical purity—
Adsorbent: 0.25-mm layer of chromatographic cellulose.
Test solution— Open 2 Capsules and place them in a suitable container, add 8 mL of methanol, and mix.
Reference solution: 40 mg of urea per mL, in water.
Application volume: 20 µL of the Test solution and 4 µL of the Reference solution.
Developing solvent system: n-butanol saturated with water.
Procedure— Proceed as directed for Thin-Layer Chromatography under Chromatography 621. Locate the spots on the plate by spraying with Ehrlich's reagent. Determine the radioactivity distribution with a suitable radiation detector (see Radioactivity 821), and obtain the RF value: the RF value of the principal spot from the Test solution corresponds to that obtained from the Reference solution, and the radioactivity of the 14C band is not less than 90% of the total radioactivity.
Assay for radioactivity 821— Prepare a solution of 1 or more Capsules in 1 N hydrochloric acid. Using a liquid scintillation counter, determine the radioactivity, in MBq (or mCi) per mL by use of a calibrated system.
Auxiliary Information— Please check for your question in the FAQs before contacting USP.
Topic/Question Contact Expert Committee
Monograph Ravi Ravichandran, Ph.D.
Principal Scientific Liaison
1-301-816-8330 (SM42010) Monographs - Small Molecules 4
711 Margareth R.C. Marques, Ph.D.
Senior Scientific Liaison
1-301-816-8106 (GCDF2010) General Chapters - Dosage Forms

USP35–NF30 Page 2496
Pharmacopeial Forum: Volume No. 27(2) Page 2126

http://www.drugfuture.com/Pharma ... 5nf30s0_m13090.html

赞一下

回复此楼

守候在风中的宁静。