Search PubMed⌕ Search
Home/Archive/PubMed

PubMed · 2657273

Transdermal delivery systems.

H P Merkle
View original source ↗Export metadata ↓

Abstract

Based on a number of revolutionary ideas in the early seventies the development of transdermal delivery systems (TDS) for systemic therapy has been receiving considerable attention, both in academia and in the pharmaceutical industry. About ten years after a number of products were successfully put on the market, it has become clear that transdermal delivery of drugs not only exhibits appealing therapeutic prospects but may also provide a viable economic basis for future activities of the pharmaceutical industry. The paper will briefly stress some of the fundamentals of transdermal delivery with respect to the skin as absorption site. The main focus will be on transdermal delivery systems, covering design of transdermal systems, manufacturing of transdermal systems, polymers and adhesives, in vitro and in vivo testing of transdermal systems, principles of delivery control, and modelling of transdermal delivery. The final section will describe the fundamental strategies for enhancing drug permeation through the skin by alteration of barrier properties, approaches for thermodynamic activity increase of drug, and the iontophoretic transdermal delivery of drugs.

Explore related subjects

Administration, CutaneousChemistry, PharmaceuticalHumansSkin Physiological PhenomenaJournal ArticleReview

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

H P Merkle. 1989. Transdermal delivery systems.. https://pubmed.ncbi.nlm.nih.gov/2657273/

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2007

Safety, acceptability, and tolerability of 3 topical microbicides among heterosexual Kenyan men.

OBJECTIVES: To compare the acceptability, tolerability, and safety of 3 topical microbicide formulations (62% ethyl alcohol in emollient gel and 0.1% and 0.4% benzalkonium chloride on a sanitary wipe) for use on male genitalia. DESIGN: This triple-randomized crossover study among men attending a sexually transmitted disease (STD) clinic in Nairobi, Kenya assigned individuals without clinical evidence of an STD to apply products to the penis in a predetermined random order, each for a 2-week period with a 1-week washout period between each product. Men recorded side effects and were examined for adverse events. RESULTS: Of 39 participants, 33 (84%) completed 6 clinic visits plus 3 home visits by community health workers. Participants reported use of 62% ethanol gel and 0.1% and 0.4% benzalkonium on 99%, 99%, and 96% of daily scheduled applications; 99%, 98%, and 97% of preintercourse applications, and 99%, 94%, and 98% of postintercourse applications. All participants said they would recommend all 3 products to a friend; 72% preferred the 62% ethanol gel, 17% the 0.1% benzalkonium, and 11% the 0.4% benzalkonium. One person developed objective signs of a genital ulcer after 14 days of 0.4% benzalkonium wipe use. CONCLUSIONS: Two of the 3 topical microbicides had minimal reported adverse effects, and no adverse effects were observed during use of the ethanol gel, which was preferred by most men.

Administration, Cutaneous↗
PubMed2007

Human skin penetration of sunscreen nanoparticles: in-vitro assessment of a novel micronized zinc oxide formulation.

The extent to which topically applied solid nanoparticles can penetrate the stratum corneum and access the underlying viable epidermis and the rest of the body is a great potential safety concern. Therefore, human epidermal penetration of a novel, transparent, nanoparticulate zinc oxide sunscreen formulation was determined using Franz-type diffusion cells, 24-hour exposure and an electron microscopy to verify the location of nanoparticles in exposed membranes. Less than 0.03% of the applied zinc content penetrated the epidermis (not significantly more than the zinc detected in receptor phase following application of a placebo formulation). No particles could be detected in the lower stratum corneum or viable epidermis by electron microscopy, suggesting that minimal nanoparticle penetration occurs through the human epidermis.

Administration, Cutaneous↗
PubMed2007

Endogenous phospholipid metabolite containing topical product inhibits ultraviolet light-induced inflammation and DNA damage in human skin.

BACKGROUND: N-palmitoylethanolamine (PEA) and organic osmolytes are endogenous components of the human epidermis and are generated from phospholipids in the stratum granulosum. PEA has been shown to exert potent antioxidant and anti-inflammatory activities. The endogenous organic osmolytes such as betaine and sarcosine control skin humidity, but have also been shown to inhibit ultraviolet (UV) light-induced oxidative stress in keratinocytes. OBJECTIVES: To investigate the effect of a PEA- and organic osmolyte-containing topical product (Physiogel AI) on the development of UV light-induced erythema, thymine dimer formation and p53 tumor suppressor gene activation, as well as intercellular adhesion molecule 1 (ICAM-1) and Ki67 expression in normal human skin. METHODS: The UV-induced erythema was measured by a spectrofluorometric method. Thymine dimers, p53, ICAM-1 and Ki67 were detected in skin biopsies using immunohistochemistry. RESULTS: Physiogel AI cream significantly inhibited the development of UV light-induced erythema and thymine dimer formation in normal human skin, but did not alter the number of Ki67+ proliferating keratinocytes and the expression of p53 and ICAM-1. CONCLUSIONS: Our results suggest that PEA and organic osmolytes might represent a new generation of compounds which suppress UV-induced photodamage.

Administration, Cutaneous↗