Transdermal delivery systems in cosmetics

Transdermal drug delivery systems have become an intriguing research topic in pharmaceutical technology area and one of the most frequently developed pharmaceutical products in global market. The use of these systems can overcome associated drawbacks of other delivery routes, such as oral and parenteral. The authors will review current trends, and future applications of transdermal technologies, with specific focus on providing a comprehensive understanding of transdermal drug delivery systems and enhancement strategies. This article will initially discuss each transdermal enhancement method used in the development of first-generation transdermal products. These methods include drug/vehicle interactions, vesicles and particles, stratum corneum modification, energy-driven methods and stratum corneum bypassing techniques. Through suitable design and implementation of active stratum corneum bypassing methods, notably microneedle technology, transdermal delivery systems have been shown to deliver both low and high molecular weight drugs. Microneedle technology platforms have proven themselves to be more versatile than other transdermal systems with opportunities for intradermal delivery of drugs/biotherapeutics and therapeutic drug monitoring. These have shown that microneedles have been a prospective strategy for improving transdermal delivery systems.Graphical abstract

Transdermal drug delivery system is one of the leading technology which gives extensive benefits compared to other dosage forms. In the case of drugs having a first-pass metabolism problem, small doses of drugs can be delivered. Oral drug delivery is associated with several problems like pain interrelated with the use of injections,needles, and the researchers mainly focus on the development of the transdermal route. The aim is to provide a rationale for improvement of the transdermal system of antipsychotics by highlighting the antipsychotic formulation and safely delivering medications across the skin.The present review emphasis on the latest advances in a transdermal delivery system which acts as a platform for effective transdermal delivery of antipsychotic. By using this technique, the pharmacotherapy of patients who have psychosis can be improved. There are numeral physical methods, and the skin penetration enhancement techniques have been developed that helps in delivering drugs through the skin.This technique helps to alter the barrier properties of skin and improves the penetration of the drug.It majorly highlights the possible role of microneedle in the transdermal system and acts as a different carrier in delivering several therapeutic agents effectively. This article summarizes thenovel transdermal delivery approaches, advantages, and the choice of antipsychotropic drugs.

Transdermal Drug Delivery System (TDDS) is described as a self-contained or discrete dosage form that is applied to the intact skin. This rout of drug administration of drugs through the skin for therapeutic use is an alternative approach to oral, intravascular, subcutaneous, and transmucosal routes. The delivery of drugs through the skin to the systemic circulation provides a convenient route of administration for a variety of clinical indications. Transdermal Drug Delivery System allows continuous drug administration, use of drugs with short biological half lives, avoids increases hepatic first pass elimination and rapid termination of medication by removing the transdermal drug delivery system from the skin. Various transdermal technologies may be applied for different categories of pharmaceuticals used for the treatment of disorders of the skin or for systemic effects to treat diseases of other organs. Several transdermal products and applications include hormone replacement therapy, contraception, pain management, angina pectoris, smoking cessation, and neurological disorders such as Parkinson's disease. The most commonly used transdermal system is the skin patch using various types of technologies. Stratum corneum is the outermost layer of the skin and it is the main barrier layer for permeation of drug in transdermal delivery of drugs. So, to circumvent the barrier properties of stratum corneum and to increase the flux of drug through skin membrane various penetration enhancement techniques are used in transdermal drug delivery system. The review presents different physical and chemical methods in penetration enhancement approaches and to optimize the transdermal delivery system.

The barrier function of the skin limits transdermal medication delivery. Vesicular systems are one of the most contentious mechanisms for delivering active compounds transdermally. The discovery of elastic vesicles such transferosomes, ethosomes, cubosomes, phytosomes, and others reignited interest in creating transdermal delivery systems. Vesicular drug delivery systems are highly organised assemblies made up of one or more concentric bilayers that form when amphiphilic building units self-assemble in water. Because of their potential to localise drug activity at the site or organ of action while reducing its concentration at other places in the body, vesicular drug delivery systems are particularly significant for targeted drug delivery. The vesicular drug delivery system keeps drug activity at a specified rate, keeps drug levels in the body reasonably constant (zero order kinetics), and reduces unwanted side effects at the same time. It can also target medication delivery utilizing carriers or chemical derivatization to localise drug action in the affected tissue or organ. Vesicular drug delivery systems have been used to improve The therapeutic index, solubility, stability, and rapid degradation of a pharmacological molecule are all important factors to consider. As a result, a number of innovative vesicular drug delivery systems that allow drug targeting and prolonged or regulated drug release have been produced. This review will focus on diverse lipoidal and non-lipoidal vesicles, with a special emphasis on pharmaceutical targeting.

Transdermal drug delivery systems are pharmaceutical forms designed to administer a drug through the skin to obtain a systemic effect. They ensure a constant rate of drug administration and a prolonged action. Several different types of transdermal delivery devices are available on the market. They are either matrix or reservoir systems and their main current uses are to treat neurological disorders, pain and coronary artery disease, and as hormone replacement therapy. Transdermal drug administration has a number of advantages compared with the oral route: it avoids gastrointestinal absorption and hepatic first-pass metabolism, minimizes adverse effects arising from peak plasma drug concentrations and improves patient compliance. Compared with the parenteral route, transdermal administration entails no risk of infection. For elderly people, who are often polymedicated, transdermal drug delivery can be a good alternative route of administration. Transdermal absorption depends on passive diffusion through the different layers of the skin. As skin undergoes many structural and functional changes with increasing age, it would be useful to know whether these alterations affect the transdermal diffusion of drugs. Studies have shown that age-related changes in hydration and lipidic structure result in an increased barrier function of the stratum corneum only for relatively hydrophilic compounds. In practice, no significant differences in absorption of drugs from transdermal delivery systems have been demonstrated between young and old individuals. The need for dose adaptation in elderly patients using transdermal drug delivery systems is therefore not related to differences in skin absorption but rather to age-related cardiovascular, cerebral, hepatic and/or renal compromise, and to ensuing geriatric pharmacokinetic and pharmacodynamic changes.

Transdermal drug delivery systems (TDDS) for antibiotics have seen significant advances in recent years that aimed to improve the efficacy and safety of these drugs. TDDS offer many advantages over other conventional delivery systems such as non-invasiveness, controlled-release pattern, avoidance of first-pass metabolism. The objective of this review is to provide an overview on the recent advances in the TDDS of different groups of antibiotics including β-lactams, tetracyclines, macrolides, and lincosamides, utilized for their effective delivery through the skin and to explore the challenges associated with this field. The majority of antibiotics do not have favorable properties for passive transdermal delivery. Thus, novel strategies have been employed to improve the delivery of antibiotics through the skin, such as the use of nanotechnology (nanoparticles, solid-lipid nanoparticles, nanoemulsions, vesicular carriers, and liposomes) or the physical enhancement techniques like microneedles and ultrasound. In conclusion, the transdermal delivery systems could be a promising method for delivering antibiotics that have the potential to improve patient outcomes and enhance the efficacy of drugs. Further research and development are still needed to explore the potential of delivering more antibiotic drugs by using various transdermal drug delivery approaches.

Transdermal drug delivery system was introduced to overcome the difficulties of drug delivery through oral route. Despite their relatively higher costs, transdermal delivery systems have proved advantageous for delivery of selected drugs, such as estrogens, testosterone, clonidine and nitro-glycerine. Transdermal delivery provides a leading edge over injectable and oral routes by increasing patient compliance and avoiding first pass metabolism respectively. Topical administration of therapeutic agents offers many advantages over conventional oral and invasive methods of drug delivery. Skin is an effective medium from which absorption of the drug takes place and enters into systematic circulation over a period of time. The present article reviews the selection of drug candidates and polymers suitable to be formulated as transdermal system, advantages, disadvantages of formulation design and the methods of evaluation.

Background: Transdermal patch is a transdermal delivery system that can overcome problems in conventional drug administration such as oral drug administration. Patches can provide controlled drug release and have advantages over oral administration such as avoiding first pass metabolism, increasing drug bioavailability, avoiding adverse effects on the gastrointestinal (GI) tract, minimizing patient variability, maintaining a constant drug in plasma, and providing a stable therapeutic effect. The effectiveness of a patch is determined by the ability of the drug to release from the patch matrix and penetrate into the stratum corneum. According to the method used to make the patches, they are divided into single layer, multi-layer, reservoir system, and matrix system patches. The basic components of a patch are polymer matrix, membrane, drug, permeation enhancer, pressure-sensitive adhesives, backing film, release liner, and plasticizer. Methods of review : This review refers to several previously published data regarding physical characteristics and transdermal drug release. This review also includes some explanations regarding the patch as a transdermal drug delivery system. Conclusion: This review focuses on patch analysis methods after the manufacturing process such as physical characteristics test, in vitro drug release test, in vitro skin permeation test, skin irritation test, and stability test as well as some explanations related to transdermal drug delivery system.

Alongside oral delivery of therapeutics, transdermal delivery systems have gained increased patient acceptability over past few decades. With increasing popularity, novel techniques were employed for transdermal drug targeting which involves microneedle patches, transdermal films and hydrogel based formulations. Hydrogel forming ability along with other rheological behaviour makes natural polysaccharides an attractive option for transdermal use. Being a marine originated anionic polysaccharide, alginates are widely used in pharmaceutical, cosmetics and food industries. Alginate possesses excellent biodegradability, biocompatibility and mucoadhesive properties. Owing to many favourable properties required for transdermal drug delivery systems (TDDS), the application of alginates are increasing in recent times. This review summarizes the source and properties of alginate along with several transdermal delivery techniques including the application of alginate for respective transdermal systems.

Transdermal drug delivery systems (TDDS), particularly transdermal patches, represent a significant advancement in pharmaceutical technology, offering non-invasive drug administration through the skin. These systems provide controlled release mechanisms and improved therapeutic outcomes. The evolution of TDDS has effectively addressed various limitations of conventional drug delivery methods, by escaping first-pass metabolism and maintaining steady plasma drug concentrations. Technological innovations have introduced sophisticated materials and formulation strategies, including advanced polymer matrices, smart delivery systems, and novel permeation enhancers. The integration of nanotechnology has expanded the scope of transdermal delivery, enabling the administration of previously unsuitable drug molecules. Current knowledge of skin structure and its barrier function has led to improved transdermal patch designs incorporating microemulsions, nanocarriers, and smart polymers. Advanced technologies such as microneedles, iontophoresis, and sonophoresis have significantly improved drug permeation capabilities. Marketed formulations demonstrate successful implementation of these technologies, while ongoing research continues to optimize characterization methods and delivery mechanisms. The development of more effective and patient-friendly transdermal systems has resulted in improved therapeutic outcomes and enhanced patient compliance, marking a significant advancement in drug delivery technology. Recent innovations suggest a promising future for transdermal delivery systems in addressing complex therapeutic challenges and meeting diverse patient needs.

A transdermal patch is a medicated adhesive patch that is applied to the skin and used to deliver a particular amount of medication into the bloodstream through the skin. It aids in the recovery of an injured bodily part. The transdermal drug delivery system (TDDS) provides an alternative safe means of drug delivery to previous intrusive techniques. In the past, topically applied lotions and ointments were the most commonly utilised systems for dermatological issues. The fact that some of these formulations cause systemic side effects indicates that they are absorbed through the skin. All topically applied medication formulations intended to transport the active ingredient into the general circulation are included in the transdermal delivery system. To overcome the skin's formidable barrier to topical medication administration, several substances have been utilised. Because of their unique qualities, such as improved bioavailability, regulated pharmaceutical release, and improved patient compliance, TDDS have recently gained increased attention. The current review focuses on the various advancements in transdermal drug delivery, as well as the various available methods for preparing transdermal patches, characterization and assessment tools for transdermal patch preparation, patents, transdermal compound clinical trials, and drug approved and future applications of transdermal drug delivery systems. As a result, in recent years, the Transdermal Drug Delivery System has received a lot of attention.

In the last decade, almost one-third of the newly discovered drugs approved by the US FDA were biomolecules and biologics. Effective delivery of therapeutic biomolecules to their target is a challenging issue. Innovations in drug delivery systems have improved the efficiency of many of new biopharmaceuticals. Designing of novel transdermal delivery systems has been one of the most important pharmaceutical innovations, which offers a number of advantages. The cell-penetrating peptides have been increasingly used to mediate delivery of bimolecular cargoes such as small molecules, small interfering RNA nucleotides, drug-loaded nanoparticles, proteins, and peptides, both in vitro and in vivo, without using any receptors and without causing any significant membrane damage. Among several different drug delivery routes, application of cell-penetrating peptides in the topical and transdermal delivery systems has recently garnered tremendous attention in both cosmeceutical and pharmaceutical research and industries. In this review, we discuss history of cell-penetrating peptides, cell-penetrating peptide/cargo complex formation, and their mechanisms of cell and skin transduction.

Transdermal Patches have been contributing important part to the pharmaceutical industry and medical practice by providing advances in delivery of treatment with existing and novel drugs. Transdermal drug delivery system has made great contribution in the medical practices but many researches are undergoing to achieve its full potential. Transdermal drug delivery system was came into existence to overcome difficulties of drug delivery especially oral route. Transdermal drug delivery refers to means of delivering drugs through the surface of the skin for local or systemic treatment. The drug functions after absorption through skin into the systemic circulation via capillary action at certain rate. Transdermal patches are now widely used as topical and transdermal delivery systems. These patches are a significant result of advancements in skin science, technology, and knowledge, which have been created via trial and error, clinical observation, and evidence-based investigations dating back to the earliest human records. A transdermal patch is a medicated adhesive patch that is applied to the skin and used to deliver a precise amount of medicine into the bloodstream via the skin. A benefit of transdermal medication administration over other forms of delivery systems such as oral, topical, intravenous (i.v.), intramuscular (i.m.), and so on is that it is non-invasive. Transdermal patches provide medication to the patient in a regulated manner, either by a porous membrane covering a reservoir of medication or by body heat melting tiny layers of drug contained in the adhesive. This review article covers the basics of transdermal patches, such as the many types of patches, how they're made, and what factors influence them, among other things.
 Keyword: Skin Delivery, Transdermal Drug Delivery System, Transdermal Excipients, Pulmonary Arterial Hypertension, Sildenafil Citrate.

This study assessed conditions necessary for at least a 2-year, ambient temperature storage stability of the peptide parathyroid hormone 1-34, or PTH(1-34), coated on a novel transdermal microprojection delivery system, or ZP-PTH. Liquid coating characterization of high concentration PTH(1-34) formulations (>20% w/w) was assessed by viscosity and contact angle measurements along with RP-HPLC and SEC-HPLC. Solid-state coating morphology of PTH(1-34) on microprojection arrays was determined by SEM, and stability on storage was assessed after dissolution and testing with stability indicating assays. Internal vapor analysis was performed to detect and quantify volatile organics released by patch components into the headspace inside the final package. Aggregation and oxidation were the primary degradation mechanisms for solid-state PTH(1-34) in this transdermal delivery system. Although these two degradation pathways can be retarded by appropriate stabilizers and use of foil pouch packaging (nitrogen purged and desiccant), the solid-state drug formulation's compatibility with patch components, particularly the plastic retainer ring, surprisingly dictated PTH(1-34) stability. Internal vapor analysis demonstrated that PTH(1-34) was particularly vulnerable to vapors such as moisture, oxygen, and outgassed formaldehyde, and each of these volatiles played a unique and significant role in PTH(1-34)'s degradation mechanism. Identifying degradation mechanisms of volatile compounds on solid-state PTH(1-34) peptide stability allowed for the rationale for selection of final formulation, system components and packaging conditions. A >2-yr, ambient temperature storage stability was demonstrated for solid-state drug coated on a novel transdermal microprojection delivery system. This system was successfully tested in a Phase 2 clinical trial for the treatment of post-menopausal women with osteoporosis.

In the recent decade, skin delivery (topical and transdermal) has gained an unprecedented popularity, especially due to increased incidences of chronic skin diseases, demand for targeted and patient compliant delivery and interest in life cycle management strategies among pharmaceutical companies. Transdermal drug delivery system was presented to overcome the difficulties of drug delivery especially oral route. Transdermal drug delivery refers to a means of delivering drugs through the surface of the skin for local or systemic treatment. The drug functions after absorption through the skin into the systemic circulation via capillary action at a certain rate. Transdermal patches are now widely used as cosmetic, topical and transdermal delivery systems. These patches represent a key outcome from the growth in skin science, technology and expertise developed through trial and error, clinical observation and evidence-based studies that date back to the first existing human records. A transdermal patch is a medicated adhesive patch that is placed on the skin to deliver a specific dose of medication through skin and into the bloodstream. An advantage of a transdermal drug delivery route over other types of delivery system such as oral, topical, intravenous (i.v.), intramuscular (i.m.), etc. is that the patch provides a controlled release of the medication into the patient, usually through either a porous membrane covering a reservoir of medication or through body heat melting thin layers of medication embedded in the adhesive. The main disadvantage to transdermal delivery systems stems from the fact that the skin composition offers very effective barrier that allow only small molecule based drugs to penetrate the skin and pass through the barrier. Sildenafil citrate (SLD) is a selective cyclic guanosine monophosphate-specific phosphodiesterase type 5 inhibitor used for the oral treatment of erectile dysfunction and more recently, it has been used for the treatment of pulmonary arterial hypertension and the enhancement of uteroplacental perfusion in case of fetal growth retardation. The challenges facing the oral administration of the drug include poor bioavailability and short duration of action that requires frequent administration. The main objective of transdermal drug delivery system is to deliver drugs into systemic circulation through skin at predetermined rate with minimal inter and intrapatient variations. Keyword: Skin delivery, Transdermal drug delivery, Oral rout, Sildenafil citrate, Pulmonary arterial hypertension