电场方向对咖啡因电穿孔与离子导入经皮渗透的影响比较

目的研究电穿孔及离子导入时电场方向对分子型药物咖啡因经皮渗透的影响。方法采用双室扩散池方法,进行咖啡因饱和水溶液经人尸体皮肤被动扩散,电穿孔导入(指数衰减型脉冲,脉冲幅度为350 V,脉冲率为4次.m in-1,脉冲数为25,放电容量为22μF)、离子导入[0.25 mA.(cm2)-1,4 h]实验,考察电穿孔及离子导入对药物经皮渗透速率、累积经皮渗透量的影响,比较电穿孔与离子导入的促透作用。结果电穿孔与离子导入的咖啡因经皮渗透速率和累积渗透量均显著大于被动扩散。电场方向改变,电穿孔的促透作用无明显改变,离子导入的促透作用明显改变,正极离子导入的促透作用显著大于负极导入。在该实验条件下,外加脉冲的促透作用显著低于离子导入。结论与被动扩散相比,电穿孔和离子导入可显著增加分子型药物咖啡因的经皮渗透速率和累积渗透量。电场方向对电穿孔的促透作用无影响,而对离子导入的促透作用有明显影响。     

桉叶油和氮酮对替硝唑凝胶剂体外透皮释药的研究

目的：研制替硝唑凝胶剂，考察混合促进剂桉叶油和氮酮对替硝唑透皮吸收作用的影响。方法：采用改良Franz直立式释放池，以离体鼠皮为透皮屏障，使用不同浓度的混合桉叶油和氮酮，测量替硝唑的透皮吸收量。结果：含2％桉叶油和2％氮酮的替硝唑凝胶与不含桉叶油和氮酮的替硝唑凝胶之间，其透皮速率增加了291％。结论：不同浓度的混合促进剂可不同程度地促进替硝唑的透皮吸收效果，其中以2％桉叶油加氮酮组成的混合促进剂作用最显著。     

按叶油和薄荷素对替硝唑凝胶剂体外透皮释药的研究

目的研制替硝唑凝胶剂,考察混合促进剂桉叶油和薄荷素油对替哨唑透皮吸收作用的影响.方法采用改良Franz直立式释放池,以离体鼠皮为透皮屏障,使用不同浓度的混合桉叶油和薄荷素油,测量替硝唑的透皮吸收量.结果含2%桉叶油和1%薄荷素油的替硝唑凝胶与不合桉叶油和薄荷素油的替硝唑凝胶之间,其透皮速率增加了265%.结论不同浓度的混合促进剂均可不同程度促进替硝唑的透皮吸收效果,其中以2%桉叶油加1%薄荷素油组成的混合促进剂作用最显著.     

桉叶油和薄荷素对替硝唑凝胶剂体外透皮释药的研究

目的：研制替硝唑凝胶剂、考察混合促进剂桉叶油和薄荷素油对替硝唑透皮吸收作用的影响。方法：采用改良Franz直立式释放池，以离体鼠皮为透皮屏障，使用不同浓度的混合桉叶油和薄荷素油，测量替硝唑的透皮吸收量。结果：含2％桉叶油和1％薄荷素油的替硝唑凝胶与不含桉叶油和薄荷素油的替硝唑凝胶之间，其透皮速率增加了265％，结论：不同浓度的混合促进剂均可不同程度促进替硝唑的透皮吸收效果，其中以2％桉叶油加1％薄荷素油组成的混合促进剂作用最显著。     

10种处方制剂中替硝唑的体外透皮吸收

目的：了解不同处方制剂中替硝唑的透皮吸收。方法：以简单小室为扩散池，离体大鼠皮肤为透皮屏障，用一阶导数分光光度法测定替硝唑含量，计算累计透皮量，渗透速率。结果：10种处方制剂中替硝唑的透皮吸收差别较大，透皮量以含3％月桂氮Zhuo酮的醇水溶液中透皮速度最高。结论：本方法简单,结果可靠。     

透皮促进剂在经皮给药系统中的应用近况

透皮促进剂是指所有能够增加药物透皮速度而对皮肤不造成严重刺激和损害的物质。近年来 ,经皮给药系统的基础实验取得了可喜进展 ,透皮制剂的组方及用现代方法对药物在体内或体外透皮吸收进行较系统的研究成绩显著。经皮给药的理论基础为给药后 ,药物能迅速穿透皮肤 ,被吸收进入血液循环而产生疗效。因此 ,研究经皮给药制剂时首先必须解决药物对皮肤的穿透性和透皮速率。目前的技术多采用添加月桂氮酮(Ａｚｏｎｅ)、亚油酸、丙二醇 (ＰＧ)等透皮促进剂来增加药物的穿透性和提高药物的透皮速率。在应用这些促进剂时 ,研究者又发现按一定比…     

pH对萘普生透皮速率的影响

目的：通过对萘普生在不同ｐＨ条件下透皮速率的研究，考察介质ｐＨ对药物透皮吸收的影响。方法：测定萘普生不同ｐＨ介质中的溶解度，使用Ｖａｌｉａ－Ｃｈｉｅｎ扩散池测定萘普生通过大鼠皮肤的体外透皮速率。结果：萘普生的稳态透皮速率随ｐＨ升高而增大，而表观渗透系数则ｐＨ升高而减少。根据分子型药物与离子型药物通过皮肤的途径不同，用平行扩散模型建立了稳态透皮速率和表观渗透系数与氢离子浓度的关系式。结论：当药物在介     

吡罗昔康离子导入的实验研究

探讨了离子导入和月桂氮酮预处理对吡罗昔康通过离体大鼠皮肤的影响，选用Ｖａｌｉａ－Ｃｈｉｅｎ扩散池和改良的Ｆｒａｎｚ扩散池，得到吡罗昔康饱和液及其膜剂的透皮速率分别为４．８±０．１７和１．０±０．０４μｇ／ｈ·ｃｍ－２，采用电流强度为０．８ｍＡ的离子导入，药物的透皮速率分别增加１１倍和８倍．另外，月桂氮酮预处理合用离子导入能产生协同作用，其透皮速率为单用月桂氮酮与单用电场透皮速率之和的４倍。     

离子导入对卡托普利透皮吸收的促进作用(英文)

目的:研究离子导入技术对卡托普利透皮吸收的促进作用。方法:应用离子导入技术研究了卡托普利体外透过大鼠离体皮肤的影响因素,并进行了卡托普利水凝胶贴片大鼠在体的试验,测定了血药浓度的变化。结果:离子导入技术可以有效地促进卡托普利的透皮吸收,透皮速率增加约7倍。药物贮库中的各种因素如pH,离子强度,药物浓度和电流强度均影响药物的透皮速率。随着pH的增加,离子强度的减小,药物浓度的增加及电流强度的增加,透皮速率也增加。大鼠在体试验也表明用药1h后血药浓度即可达到坪值(约0.9μg/mL),并在整个试验阶段维持稳定。结论:离子导入可以有效地促进卡托普利的透皮吸收。     

薄荷脑促进替硝唑凝胶经皮渗透作用

采用透皮扩散装置和鼠皮进行了薄荷脑促进替硝唑凝胶经皮渗透作用的研究。结果表明：不同浓度的薄荷脑促进剂均可不同程度地促进替硝唑凝胶的透皮吸收效果，其中2％薄荷脑透皮促进作用最显著。     

Influence of electrical and chemical factors on transdermal iontophoretic delivery of three diclofenac salts

The aim of this present study was to investigate the in vitro transdermal iontophoretic delivery of three diclofenac salts--diclofenac sodium (DFS), diclofenac potassium (DFP), and diclofenac diethylammonium (DFD). A series of physicochemical and electrical variables which might affect iontophoretic permeation of diclofenac salts was studied. Application of 0.3 mA/cm2 current density significantly increased the transdermal flux of diclofenac salts as compared to passive transport. The iontophoretic enhancement increased in the order of DFS>DFP>DFD. The permeability coefficient of diclofenac salts all decreased with increasing donor concentration during iontophoresis. The addition of buffer ions and salt ions such as NaCl, KCl, and C4H12ClN reduced the permeation of diclofenac salts due to competition. However, this effect was lesser for DFD than for DFS and DFP. Comparing the various application modes of iontophoresis, the discontinuous on/off mode showed lower but more constant flux than the continuous mode.     

Human Calcitonin Delivery in Rats by Iontophoresis

Abstract— In-vitro iontophoresis (0·33 mA cm⁻²) of calcitonin (50 μg mL⁻¹, pH 4) was performed with the hairless rat skin model. Direct current was as potent as pulse current (2·5 kHz on/off 1/1) iontophoresis in promoting transdermal permeation of calcitonin. Increase in duration of current application from 20 min to 1 h did not increase calcitonin flux. Results suggest that calcitonin can be blocked in the skin pores through which it travels or can accumulate in the skin and be progressively released from the depot. Invivo experiments showed that transdermal iontophoretic administration of calcitonin induced a hypocalcaemic effect in rats.     

Combined strategies for enhancing the transdermal absorption of midazolam through human skin

Objectives Midazolam administration by intravenous or intramuscular injection produces pain and stress. For this reason, alternative methods of administration have been proposed. The transdermal administration of midazolam could improve patient comfort, which is especially important for children in the pre‐operative period. We aimed to assess the effect of iontophoresis and chemical percutaneous enhancers applied individually and together, to determine if a synergistic effect is achieved when both enhancement techniques are simultaneously employed. Methods This work reports the characterization of the passive diffusion of midazolam hydrochloride through human skin in vitro and evaluates the effect of iontophoresis application and chemical percutaneous enhancers on said diffusion when employed both individually and in combination. Key findings Percutaneous absorption assays demonstrated that the physical technique of iontophoresis, when applied alone, moderately increased midazolam hydrochloride permeation flux through human skin, producing a similar effect to that obtained with R‐(+)‐limonene chemical enhancer. Among the strategies assayed, it was observed that Azone produced the most pronounced enhancement effect when applied separately. The combination of pre‐treatment with Azone and iontophoresis exhibited a higher capacity for enhancing the transdermal flux of midazolam through human skin than Azone alone. Conclusions In conclusion, when applied individually, Azone exhibited the greatest enhancement effect on the transdermal diffusion of midazolam of the various strategies assayed. The combination of Azone and iontophoresis produce the highest transdermal steady‐state flux of midazolam but no synergic effect was achieved when the two enhancement strategies were applied in combination, showing that although selecting the best conditions for iontophoresis application, it is less effective for augmenting the transdermal delivery of midazolam than the chemical enhancer Azone.     

Transdermal iontophoresis of sodium nonivamide acetate. V. Combined effect of physical enhancement methods

The effect of iontophoresis combined with treatment of other physical enhancement methods such as electroporation, low frequency ultrasound, and erbium:YAG (yttrium-aluminum-garnet) laser on the transdermal delivery of sodium nonivamide acetate (SNA) was examined in this present study. Iontophoresis increased the transdermal flux of SNA in vitro as compared to the passive diffusion without any enhancement. Furthermore, iontophoresis was always the most potent enhancement method for SNA permeation among the physical enhancement methods tested. Pulsing of high voltages (electroporation) followed by iontophoresis did not result in increased transport over iontophoresis alone. However, electroporation shortened the onset of transdermal iontophoretic delivery of SNA. Pretreatment of low frequency ultrasound (sonophoresis) alone on skin did not increase the skin permeation of SNA. The combination of iontophoresis and sonophoresis increased transdermal SNA transport more than each method by itself. The enhancement of drug transport across shunt routes and reduction of the threshold voltage in the presence of an electric field may contribute to this synergistic effect. Use of an erbium:YAG laser was a good method for enhancing transdermal absorption of SNA because it allows precise control of stratum corneum (SC) removal, and this ablation of SC could be reversible to the original normal status. The combination of laser treatment and iontophoresis also synergized the skin permeation of SNA, possibly due to a gradual drop in the electric resistance of the skin. The results in this present study point out that the choice of certain conditions with suitable physical enhancement methods can induce a synergistic effect on transdermal delivery of SNA during iontophoresis.     

Electronically facilitated transdermal delivery of human parathyroid hormone (1-34)

Electronically facilitated transdermal delivery of human parathyroid hormone (1-34), hPTH (1-34), was investigated in vitro, using dermatomed porcine skin. The effect of iontophoretic current density, electroporative pulse voltages and also electroporation followed by iontophoresis was investigated on the in vitro percutaneous absorption of hPTH (1-34). Iontophoresis at 0.5 mA/cm2 current density significantly enhanced (P<0.05) the flux of hPTH (1-34) in comparison to passive flux. Electroporation pulses of 100, 200 and 300 V significantly increased (P<0.05) the flux of hPTH (1-34) in comparison with the passive as well as iontophoretic flux at 0.5 mA/cm2. The electroporative flux of hPTH (1-34) was found to vary linearly (R2 = 0.97) with the pulse amplitude. The principal barrier of the skin, stratum corneum, was found perturbed following the pulses as evident by light microscopy studies. The application of electroporation pulses followed by iontophoresis further increased the flux by several fold. The flux of hPTH (1-34) with the electroporation pulses of 100 and 300 V followed by iontophoresis at 0.2 mA/cm2 was 10- and 5-fold higher, respectively, in comparison to the flux with corresponding pulses alone. This shows the synergistic effect of iontophoresis in combination with electroporation on skin permeability of hPTH (1-34). The results indicate the possibility of designing controlled transdermal delivery systems for hPTH (1-34) using electroporation followed by iontophoresis.     

盐酸丁卡因离子导入凝胶的研究

目的研究电流强度对盐酸丁卡因离子导入凝胶的渗透速率的影响。方法以盐酸丁卡因为模型药物,采用离子导入作为促透方法,分别测定不同电流强度下的盐酸丁卡因离子导入凝胶在离子导入后接受室溶液的吸收度,计算它们的稳态透皮速率。结果电流强度为0.05,0.1,0.15,0.2和0.25mA时,稳态透皮速率分别为10.18,22.94,34.62,41.60和51.35μg/cm2×h。结论在一定的电流强度下,漏槽条件下,盐酸丁卡因离子导入凝胶渗透速率与电流强度有较好的线性关系。     

Transdermal iontophoresis of sodium nonivamide acetate I. Consideration of electrical and chemical factors

Transdermal iontophoresis is a process which enhances skin permeation of ionized species by an electrical field as driving force. The aim of this present study was to investigate the transdermal iontophoresis of a newly designed capsaicin derivative, sodium nonivamide acetate (SNA). Studies of electrical and physicochemical factors acting on the kinetics of in vitro iontophoresis were performed. Iontophoresis increased the transdermal penetration flux of SNA as compared to the passive diffusion in this study. Several application modes which possessed the same electrical energy had been researched. The iontophoretic flux of SNA increased following the decrease of donor buffer pH values. This trend could be due to the physiological property of skin and electro-osmotic flow presented. Comparing the various application modes, the discontinuous on/off cyclic current mode showed higher penetration capacity than did continuous mode which was due to the intensity of effective current which would not decay for on/off cyclic application of iontophoresis. The result of the present study is particularly helpful in the development of a SNA transdermal iontophoretic delivery system.     

电致孔和离子导入对胰岛素经皮渗透的促进作用

目的研究电致孔(EP)和离子导入(ION)对胰岛素经皮渗透的影响。方法以水平双室扩散池的方法,研究电致孔与离子导入联合应用对胰岛素经皮渗透的促进作用,并与单独使用离子导入或电致孔进行比较。结果 电致孔与离子导入联用比单独离子导入显著增加胰岛素的经皮渗透性(P<0.05),且高电压比低电压电致孔离子导入显著增加胰岛素的渗透速率(P<0.01)。胰岛素离子导入前,500 V电压,给90次脉冲(指数衰减脉冲,每次脉冲持续时间20～24 ms,3次·min^-1),导致了透皮流速(Flux)的快速稳定增加。结论电致孔和离子导入联用能明显促进大分子胰岛素的经皮渗透性。     

渗透促进剂对胰岛素体外经皮离子导入渗透性的影响

本文考察了某些渗透促进剂如月桂氮Zhuo酮（AZ）、油酸（OA）、泊洛沙姆（POL）和丙二醇（PG）等对胰岛素体外经皮离子导入渗透性的影响。结果表明AZ对离子导入具有协同作用，PG能够增强这种作用，三者并用对胰岛素的经皮渗透具有特别显著的促渗效果。5％AZ／PG与离子导入并用后，较单独离子导入处理组的促渗因子为2.75。OA不能增强离子导入的作用，离子导入与某些渗透促进剂并用为胰岛素等大分子多肽类药物的透皮给药提供了新的思路和可能。     

双戊烯对替硝唑透皮吸收促进作用的研究

目的：研究双戊烯对替硝唑的促透效果,为透皮促进剂的选择提供参考。方法：通过离体小鼠皮肤渗稼透释药实验,测定含不同浓度双戊烯和氮酮对替硝唑溶液促透效果。结果：不同浓度促透剂对替硝唑的透皮吸收促进效果大小顺序为3％双戊烯＞2％双戊烯≈4％氮酮＞3％氮酮。结论：3％双戊烯对替硝唑溶液有显著的透皮促进作用,与其他浓度的双戊烯和氮酮相比具有显著差异（P＜0.05)。