紫外分光光度法测定米诺地尔洗剂中米诺地尔的含量

目的建立米诺地尔洗剂的含量测定方法.方法采用紫外分光光度法测定洗剂中米诺地尔的含量.结果测定波长231 nm,在1～7 μg/ml浓度范围内吸收度与浓度线性关系良好(r=0.9998),平均回收率99.29%,RSD 0.05%(n=4).结论本法方便快捷,结果准确,可用于米诺地尔洗剂的质量控制.     

紫外分光光度法测定米诺地尔洗剂中米诺地尔的含量

目的建立米诺地尔洗剂的含量测定方法。方法采用紫外分光光度法测定洗剂中米诺地尔的含量。结果测定波长231nm,在1～7μg/ml浓度范围内吸收度与浓度线性关系良好(r=0.9998),平均回收率99.29%,RSD0.05%(n=4)。结论本法方便快捷,结果准确,可用于米诺地尔洗剂的质量控制。     

紫外分光光度法测定米诺地尔洗剂中米诺地尔的含量

目的 建立米诺地尔洗剂的含量测定方法。方法 采用紫外分光光度法测定洗剂中米诺地尔的含量。结果 测定波长231nm，在1～7μg／ml浓度范围内吸收度与浓度线性关系良好(r=0．9998)，平均回收率99．29％，RSD 0．05％(n=4)。结论 本法方便快捷，结果准确，可用于米诺地尔洗剂的质量控制。     

米诺地尔溶液的制备及其质量控制

目的:制备米诺地尔溶液,建立其含量测定方法.方法:通过紫外分光光度法,于286nm处测定米诺地尔含量.结果:在4～16μg·mL-1范围内,米诺地尔吸收度与浓度呈良好的线性关系,其回归方程为C(μg·mL-1)=17.40A-0.1051(γ=1.0000),平均回收率为99.8%(RSD为0.74%).结论:本方法操作简便、准确、可靠,可作为本品的质量控制.     

米诺地尔凝胶的制备及质量控制

目的 :制备米诺地尔凝胶 ,建立其质量控制方法。方法 :以卡波姆934为基质制备凝胶 ,采用紫外分光光度法测定主药米诺地尔含量 ,并考察其稳定性。结果 :米诺地尔线性范围为2～10μg/ml(r=0. 9999) ,平均回收率为99.8 % ,RSD=0.67 % (n=4) ,凝胶稳定性良好。结论 :本处方设计合理 ,质量控制方法简便、准确、可行 ,制剂稳定性好。     

米诺地尔生发液的制备及质量控制

目的:探讨米诺地尔生发液的制备方法及质量控制.方法:采用紫外分光光度法测定含量.结果:米诺地尔在2～10μg*ml-1浓度范围内与吸收度呈良好线性关系(r=0.9999,n=5),回收率为99.84%,RSD为0.36%(n=9).结论:该制剂稳定、制备简便,质控方法准确.     

HPLC法测定米诺地尔搽剂中米诺地尔的含量

目的建立用于测定米诺地尔搽剂中米诺地尔含量的HPLE法。方法采用HPLC法测定,色谱柱：Hypersil ODS2 （250mm×4．6mm,5μm）,流动相：V（甲醇）：V（0．1％三乙胺水溶液）=25：75,检测波长285nm,柱温30℃,流速1mL·min^-1。结果米诺地尔在质量浓度6．6—39．6mg·L^-1内与峰面积之间呈现良好的线性关系（r=0．9996）,平均回收率为107．99％,RSD为0．99％。结论本方法简便、灵敏度高,能准确检测米诺地尔搽剂中米诺地尔的含量,可作为米诺地尔搽剂质量控制的有效测量方法。     

高效液相色谱法测定米诺地尔搽剂中米诺地尔的含量

目的建立测定米诺地尔搽剂中米诺地尔含量的高效液相色谱(HPLC)检验方法。方法采用Nova-PaKC18色谱柱(150mm×4.6mm,5μm),流动相为甲醇-水(70∶30),流速为1.0mL/min,检测波长为285nm。结果米诺地尔在2.5～20mg/L浓度范围内含量与峰面积比呈现良好的线性关系(r=0.9999),平均回收率为99.5%,RSD为1.85%,最低检出浓度为0.5mg/L。结论本法能准确检测米诺地尔搽剂中米诺地尔的含量,因此可作为米诺地尔搽剂质量控制的有效测量方法。     

高效液相色谱法测定生发素中米诺地尔含量

目的建立测定生发素中米诺地尔含量的高效液相色谱法。方法采用C18色谱柱(200mm×4.6mm,5μm),流动相为0.03mol/L的K2HPO4溶液(pH=3.3)-甲醇(55∶45),检测波长287 nm,流速0.9 mL/min,柱温30℃,进样量10μL。结果米诺地尔质量浓度在2.16～15.12μg/mL范围内与峰面积线性关系良好(r=0.999 96),平均回收率为99.36%,RSD为1.21%(n=6)。结论高效液相色谱法简便、准确、灵敏,适用于生发素中米诺地尔的含量测定。     

复方桑参米诺地尔搽剂中米诺地尔的HPLCLC定

建立了高效液相色谱法测定复方桑参米诺地尔搽剂中米诺地尔的含量。采用C18柱，流动相为甲醇．乙腈·水（40：10：50），流速1．2ml／min，检测波长230nm，内标为对乙酰氨基酚。米诺地尔在3．649。6μg／ml浓度范围内线性关系良好（r=0．9999），回收率大于98％，日内和日间RSD均小于1％。     

紫外分光光度法测定米诺地尔酊的含量

目的：用紫外分光光度法测米诺地尔酊中米诺地尔的含量,为该药提供质量控制方法。方法：紫外分光光度法。结果：米诺地尔浓度在０．５～６μｇ·ｍｌ－１范围内吸收度与溶液浓度呈线性关系（ｒ＝０．９９９９,ｎ＝５）,回收率为１００．４％,ＲＳＤ为０．１０％（ｎ＝５）。结论：该法能作为米诺地尔酊含量测定的方法,而且简便、准确、快速。     

Evaluation of minoxidil

The chemistry, pharmacokinetics, mechanism of action, clinical studies, adverse effects, toxicology, indications, contraindications, drug interactions, and dosing of minoxidil, a recently approved antihypertensive agent, are reviewed. Minoxidil is an orally effective vasodilator that selectively relaxes peripheral arteriolar smooth muscle, Reflex tachycardia, renin stimulation, and sodium retention occur when minoxidil is used and so it requires the concomitant use of a diuretic and a sympathoplegic agent, usually a beta blocker. Hirsutism and pericardial effusions are additional adverse effects. Minoxidil is indicated in the management of severe hypertension in patients who do not respond to standard antihypertensive agents. In controlled and unctrolled studies, minoxidil was effective in patients with hypertension secondary to renal or renovascular disease and in patients with essential hypertension. Minoxidil is a potent antihypertensive agent with adverse effects that limit its use to patients resistant or intolerant to other drugs.     

米诺地尔醇脂质体的制备

目的制备米诺地尔醇脂质体并评价其质量。方法采用乙醇注入法制备米诺地尔醇脂质体,以包封率为评价指标进行正交试验筛选出最佳的处方和工艺。采用HPLC测定主药含量、透析袋法测定醇脂质体的包封率。并对其粒径、电位、包封率等理化性质进行研究。结果各因素最佳的水平组合：药脂重量比为1∶10、胆固醇与大豆磷脂的重量比为1∶2、无水乙醇为处方量的30%。所制醇脂质体为乳黄色,平均粒径为1.103μm,Zeta电位为-3.69 mV,平均包封率为66.7%。结论米诺地尔醇脂质体的制备工艺简便可行,质量稳定可控,为开发新剂型奠定了实验基础。     

Monilethrix treated with minoxidil

In literature many different therapies are proposed to treat Monilethrix, but a definitive therapy still doe not exist. We decided to treat four patients affected by Monilethrix, with topical minoxidil 2%, 1 ml night and day for 1 year. Minoxidil led to a an increase of normal hair shaft without any side effects in all the patients. Therefore topical minoxidil 2% could be considered a good therapy to treat Monilethrix.     

Hair growth effect of minoxidil

The length and size of hair are depend on the anagen term in its hair cycle. It has been reported that the some cell growth factors, such as VEGF, FGF-5S, IGF-1 and KGF, induce the proliferation of cells in the matrix, dermal papilla and dermal papillary vascular system and increase the amount of extra cellular matrix in dermal papilla and then maintain follicles in the anagen phase. On the other hand, negative factors, like FGF-5, thrombospondin, or still unknown ones, terminate the anagen phase. If the negative factors become dominant against cell proliferation factors according to fulfilling some time set by the biological clock for hair follicles, TGF beta induced in the matrix tissues evokes apoptosis of matrix cells and shifts the follicles from anagen to catagen. Androgenetic alopecia is caused by miniaturizing of hair follicles located in the frontal or crown part of scalp and are hereditarily more sensitive to androgen. In their hair cycles, the androgen shortens the anagen phase of follicles and shifts them to the catagen phase earlier than usual. The mode of action of hair growth effect of minoxidil is not completely elucidated, but the most plausible explanation proposed here is that minoxidil works as a sulfonylurea receptor (SUR) activator and prolongs the anagen phase of hair follicles in the following manner: minoxidil (1) induces cell growth factors such as VEGF, HGF, IGF-1 and potentiates HGF and IGF-1 actions by the activation of uncoupled SUR on the plasma membrane of dermal papilla cells, (2) inhibits of TGF beta induced apoptosis of hair matrix cells by opening the Kir 6.0 channel pore coupled with SUR on the mitochondrial inner membrane, and (3) dilates hair follicle arteries and increases blood flow in dermal papilla by opening the Kir 6.0 channel pore coupled with SUR on the plasma membrane of vascular smooth muscle cells.     

Sulfation of minoxidil by liver sulfotransferase

The 100,000 g supernatant fraction of rat liver homogenate contains a sulfotransferase activity which catalyzes the sulfation of minoxidil. Synthetic minoxidil N-O sulfate and the enzyme synthesized product had identical Chromatographie characteristics on high pressure liquid chromatography. Minoxidil sulfate, which yields minoxidil when treated with sulfatase, was slowly hydrolyzed in water. Several N-oxides of other heterocycles, including several other pyrimidines, triazines and imidazoles, were also substrates for this sulfotransferase.     

Radioimmunoassay of minoxidil in human serum

A simple, sensitive, and specific radioimmunoassay for determining minoxidil was developed. Antiserums to two minoxidil haptens were compared for cross-reactivity and assay levels on human serums. One antiserum had little cross-reactivity with minoxidil metabolites. The radioimmunoassay is specific for determining minoxidil directly in serum without extraction. Human serum minoxidil levels were determined from a single oral dose.     

Topical minoxidil therapy for hair regrowth

The pathogenesis of hair loss, the postulated mechanisms of minoxidil action on hair growth, and clinical trials, adverse reactions, experimental formulations, and percutaneous absorption of topical minoxidil preparations are reviewed. Topical minoxidil seems to normalize hair follicles and increase blood flow to the scalp. In clinical trials of various formulations, results have varied. Improved hair growth occurred after four to six months of therapy; twice-daily application seems to be indicated. The most frequently reported adverse reactions are mild scalp dryness and irritation and, rarely, allergic contact dermatitis. Current recommendations are to reserve topical minoxidil for patients with normal cardiovascular status and to routinely monitor blood pressure, heart rate, and electrocardiographic changes. A new drug application is pending with FDA for use of topical minoxidil in androgenetic alopecia (male-pattern baldness), which is genetically determined and apparently stimulated by androgens. For alopecia areata, which involves hair loss on the body or scalp, usually patchy and of sudden onset, no reliable treatment has been found, although minoxidil may be efficacious in some patients. Minoxidil has generated new interest in hair-loss research. The etiology of hair loss must be better understood before more effective treatment regimens can be designed.