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McNeill, Stephen C.; Potts, Russell O.; Francoeur, Michael L.

doi:10.1023/a:1015854728278

Cited by 100 publications

(10 citation statements)

References 6 publications

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“…4 The epidermal lipid biochemistry in the pig has also been shown to be similar to that found in humans. 9 Several authors have performed dermal clearance kinetic studies, [10][11][12] but there appears to be no evidence in the literature of in vitro topical delivery studies performed on wound tissue. These studies have included skin scalding at 60°C, 6 tape stripping, depilation, and hypodermic needle abrasion.…”

Section: Introductionmentioning

confidence: 99%

In Vitro Model(s) for the Percutaneous Delivery of Active Tissue Repair Agents

Walker

Hulme

Rippon

et al. 1997

Journal of Pharmaceutical Sciences

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There is a need to evaluate the permeability of human ulcerated tissue and periulcer tissue in order to assess the possible treatment of such a localized pathological lesion with a topical therapy. In vitro percutaneous absorption studies were undertaken to evaluate an animal model that may mimic this clinical situation. Porcine skin from three anatomical sites, the ear, abdomen, and dorsum; ischaemic skin (porcine and guinea pig); porcine wounds; and human skin (including periulcer and ulcerated tissue) were investigated, utilizing both whole skin and dermal membranes. Dermal membranes were chosen as representative of ulcerated tissue, as there would be no epidermal barrier present, and the thickness of the dermal membrane was not expected to offer any diffusional resistance to topically applied active agents. A range of chemicals with differing physicochemical properties was investigated using a Franz type diffusion cell. For all tissues a permeability coefficient (kp with units of cm h-1) was measured, along with skin thickness and tissue partition coefficient measurements. Under these experimental conditions and for the range of compounds tested, the results suggest that porcine skin, whole skin, and dermal membranes should be considered as good representative in vitro models for the topical delivery of compounds to human skin and ulcerated tissue, respectively.

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Section: Introductionmentioning

confidence: 99%

In Vitro Model(s) for the Percutaneous Delivery of Active Tissue Repair Agents

Walker

Hulme

Rippon

et al. 1997

Journal of Pharmaceutical Sciences

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“…In systemic therapy, it is necessary to transfer drug molecules from skin (application site) to cutaneous blood flow and to transport to the target organ through systemic circulation. [2][3][4][5][6][7] On the other hand, local therapy needs to accumulate drug molecules at the local site (skin, muscle and joint, etc. ), but not to eliminate into the blood flow.…”

mentioning

confidence: 99%

“…), but not to eliminate into the blood flow. [2][3][4][5][6][7] Therefore, the evaluation of drug transfer properties into local blood flow would be expected to predict the systemic and local therapeutic effects.…”

mentioning

confidence: 99%

Effect of Lipophilicity on in Vivo Iontophoretic Delivery. II. .BETA.-Blockers.

Tashiro

Sami

Shichibe

et al. 2001

Biological & Pharmaceutical Bulletin

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Transdermal drug absorption includes several sequential processes, as follows: (1) drug absorption into the skin; (2) transfer from skin to cutaneous vein; (3) transport to systemic circulation by blood flow. In systemic therapy, it is necessary to transfer drug molecules from skin (application site) to cutaneous blood flow and to transport to the target organ through systemic circulation. [2][3][4][5][6][7] On the other hand, local therapy needs to accumulate drug molecules at the local site (skin, muscle and joint, etc.), but not to eliminate into the blood flow.2-7) Therefore, the evaluation of drug transfer properties into local blood flow would be expected to predict the systemic and local therapeutic effects.Previously, we have developed a method to investigate transdermal absorption processes in vivo, whereby the drug concentrations in skin, cutaneous vein and systemic vein are measured after iontophoretic delivery of drugs to rats. 8) Further, kinetic analysis of drug transfer from skin to cutaneous vein has been established by modifying a physiological pharmacokinetic model. 9) In the previous study, we investigated the effect of drug lipophilicity on the iontophoretic transdermal absorption of non-steroidal anti-inflammatory drugs (NSAIDs) such as salicylic acid, ketoprofen, naproxen and indomethacin.10) The transfer properties of these NSAIDs from skin to cutaneous vein decreased with an increase in their lipophilicity.The NSAIDs examined previously are acidic drugs with a carboxyl group. In the present study, b-blockers were selected as basic drugs having an amino group and included atenolol (AT), pindolol (PD), metoprolol (MP), acebutolol (AB), oxprenolol (OX) and propranolol (PP). The chemical structures and physicochemical properties are listed in Table 1. 11-13) These b-blockers are adequate for evaluating the effect of lipophilicity on transdermal absorption properties, because the molecular weights are of narrow range. As an indication of drug lipophilicity, we used the logarithm of n-octanol/buffer partition coefficient (Log P), which varied from Ϫ0.11 to 1.49 (pH 7.4, 37°C).12) The difference in the lipophilicity is a consequence of the difference in the aromatic substituents of the b-blockers.Beta-blockers are used in the treatment of hypertension, angina pectoris and cardiac arrhythmia.14) Because of their short elimination half-life (from several to less than 6 h), 15) sustained release formulations for oral administration have been developed to prolong the therapeutic effects.16-21) However, the oral absorption of b-blockers is influenced by hepatic first-pass metabolism. 15,22) Thus, the development of transdermal delivery systems may be expected to achieve good maintenance of optimal blood levels and the avoidance of first-pass effects. Anodal Iontophoresis Anodal iontophoresis was performed as described previously. 10) Briefly, male SpragueDawley rats (8-10 weeks old, Charles River Japan) were anesthetized with ether throughout the experiment, and their body temperature was maintained...

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“…Topical delivery systems offer several advantages due to their localized action and the reduction of systemic side effects. 16,17 Colloidal carriers are interesting for delivering drug to skin, and various were described including, liposomes, niosomes, transferosomes, ethosomes, nanoemulsions, solid lipid nanoparticles (SLNs), and nanostructured lipid carriers (NLCs). [18][19][20][21] Our organogel particles could be very interesting vehicles for delivering lipophilic drugs to the desired site in the skin, but we sought to reduce their size for optimum permeation.…”

Section: Introductionmentioning

confidence: 99%