Formulation and Evaluation of Herbal Transdermal Patch in the treatment of Wound Healing

Transdermal drug delivery system involves the topically administered medications in self-contained, discrete dosage forms of patches, which on application to the skin deliver the drug into the systemic circulation at pre-determined and controlled rate over a prolonged time period to increase the therapeutic efficacy and reduce the side effect of the drug. Transdermal patches are a type of drug delivery system that delivers medication through the skin and into the bloodstream. Herbal transdermal patches, in particular, are an emerging area of research as they offer a natural and non invasive way to deliver therapeutic agents to the body. In the case of wound healing, the use of herbal transdermal patches can potentially provide a localized and sustained delivery of therapeutic agents to the site of the wound, promoting healing and reducing inflammation. The formulation of herbal transdermal patches involves selecting appropriate herbs that have wound healing properties and incorporating them into a patch. The herbs can be in the form of extracts, oils, or powders, and are typically combined with a polymer matrix to form the patch. The patch is then applied to the skin over the site of the wound, where it slowly releases the herbal agents into the body. To evaluate the effectiveness of herbal transdermal patches in wound healing, various parameters can be considered. These include the rate of wound healing, reduction in inflammation, pain relief, and overall improvement in the quality of the wound site. In addition, any adverse effects or reactions to the herbal agents should also be evaluated. Overall, the formulation and evaluation of herbal transdermal patches in the treatment of wound healing offers a promising avenue for developing natural and effective therapies for this common condition. However, more research is needed to fully understand the potential benefits and risks of this approach, and to optimize the formulation of herbal transdermal patches for wound healing. Herbal transdermal patches are a form of alternative medicine that delivers herbal remedies through the skin. The patches are applied topically and contain a blend of natural ingredients that are slowly released into the body over a period of time.

 Here are some of the common uses of herbal transdermal patches:

? Pain relief: Herbal patches can be used to alleviate pain and inflammation in the body. Some of the herbs commonly used for this purpose include arnica, ginger, and turmeric.

? Sleep support: Certain herbs like lavender, chamomile, and valerian root are known for their calming properties and can be used in patches to promote relaxation and improve sleep quality.

? Stress relief: Herbal patches containing adaptogenic herbs like ashwagandha, rhodiola, and holy basil can help the body cope with stress and promote a sense of calm and relaxation.

? Energy and focus: Certain herbs like ginseng, guarana, and green tea can help boost energy levels and enhance mental focus, making them useful for those who need to stay alert and focused for extended periods of time.

? Detoxification: Some herbal patches are designed to help support the body's natural detoxification processes, containing herbs like milk thistle, dandelion root, and burdock root.

It has been found that drugs from herbal origin can be utilized with enhanced efficacy by incorporating in transdermal drug patches. We tried to formulate and evaluate, curcuma longa & aloe miller herbal patch in treatment of wound healing.

Advantages of Transdermal Drug delivery System

1. It is a very convenient method for the drug delivery system.

 2. Like intravenous infusion, it also gives a constant plasma level.

 3. If toxicity develops from TDDS, patches can be removed easily.

4. It eliminates the first pass mechanism.

5. It helps to maintain the steady infusion of drugs for a prolonged period of time.

6. It is an alternate dosage form for the patient who can't tolerate oral dosage form .

7. It helps to increase therapeutic value of drugs.

8. Herbal transdermal patches help as an aid in smoking, relief stress, and detoxification.

9. It acts as the best for conventional dosage form.

10. It helps to minimise fluctuations in physiological and pharmacological response.

11. It helps to decrease side effects due to reduced plasma concentration.

12. It is helpful in administering drug having short biological half life and drug with low therapeutic index

13. It helps to administer the drug with low melting point.

14. It helps in easy termination of drug therapy at any time

15. Drugs given orally can be given as a Transdermal patch if the patient is vomiting or having diarrhoea.

16. It is non-invasive and avoids the inconvenience caused by the parenteral route.

17. It provides extended therapy with a single application..

Disadvantage of Transdermal patches

1. Drug with High molecular weight is difficult to penetrate stratum corneum

2. In this delivery system the drug dose is limitation factor

3. If drugs which are metabolised in the liver are given through the Transdermal route then results in low bioavailability.

4. The drug irritation locally or systemically are not suitable for Transdermal Drug delivery system

5. Only potent drugs can be incorporated into transdermal patches due to the natural limit of drug entry through the skin.

Mechanism of Transdermal patches Transdermal permeation of drug moiety involves the following step

1. Sorption by stratum corneum

2. Permeation of drug through viable epidermis

3. Uptake of drugs moiety by the capillary network in the dermal papillary layer

4. The drug must possess some physicochemical properties to reach target site via systematically through stratum corneum The rate of permeation of drug moiety across the skin is governed by following equation: dQ/dT = ps( Cd-Cr)

Where, Cd = concentration of penetrate in the donor phase ( On the surface of skin)

Cr = concentration of penetrate in the receptor phase (body); and

Ps = overall permeability coefficient of the skin which is defined as

Ps = Ks Dss/hs

Where K = Partition coefficient of the penetrant

DSS= Apparent diffusivity of penetrant

hs = Thickness of the skin

Components of Transdermal patches

Polymer matrix or matrices: This mainly has to release the drug from Transdermal patches dependent on or controlled by the polymer as it increases the concentration of the polymer then it forms a very dense Matrix which results in slow release rate of drug. Polymer form the backbone of transferable drug delivery system the drug diffusion across the polymer Matrix and release rate of drug depends on the concentration and various physical chemical properties of drug as well as polymer:

Ideal properties of polymer Matrix

? It should be inert and should not react with drugs.

? It must not decompose in the presence of drugs and excipients.

? It is should do not interfere in stability of drug

? It Should be easily available

? It should be in expensive

? It must not read to any type of antagonistic effect

? Itshould not result in any type of hypersensitivity reaction

Examples: Gelatin, Hydroxypropyl methyl cellulose, polyvinyl alcohol, polyvinyl chloride,.starch, PVP, polyethylene etc.

Active Ingredients: Drug reservoir is the most important component of transformer patches. It should be selected with very much intense care. Drugs that rapidly or not are the suitable agents for formulating transformal patches because ionised drug molecules have poor skin permission and penetration.

Ideal Properties of Active Ingredients:

? It should be non edited to human skin

? It should have short biological half life

? It should be potent to import the required pharmacological action

? It should not show any type of hypersensitivity reaction when administered

? It should not be toxic in nature, the drug should have the affinity towards the lipophilic and hydrophilic phases.

Penetration Enhancers: these are the substances which enhance the skin permeability by enhancing properties of skin of drug polar, nonpolar and polar, non polar are three pathways for drug penetration through skin. Penetration is enhanced by altering one of these pathways. Polar pathway can be altered by causing protein conformational changes; non polar pathway can be altered by altering the rigidity of the lipids.

Ideal Properties of Penetration Enhancer:

? It should not damage the layer of skin permanently.

? It should be pharmacologically inert

? It should be not toxic

? It should be non allergic

? It should be action specific

? It should be non irritating.

Plasticisers: they are used to reduce or minimise the brittleness of polymer film they provide or give flexibility and elasticity to the polymeric film if plasticizers are used in high concentration then they make the film sticky and damp.

Ideal Properties of Plasticizer:

? It should be easy to handle

? It should be non reactive and non irritant

? It should be pharmacologically inert

? It should not affect the stability of drug

? It should be cost effective

? It should be easily and radley available.

Examples: Glycerol, Propylene glycol, Dibutyl phthalates, polyethylene glycol.

1. Drug reservoirs: this is a component that contains one polymer or the combination of polymers in various different concentrations and ratios.

2. Backing Laminates: this helps to give and provide support. They should prevent the release of drug surfaces which are not in contact with skin. It should be compatible with drugs and excipients. While selecting the flexibility, strength, and elasticity should be considered. This imparting appearance flexibility, occlusions to the transdermal delivery system. While selecting backing Laminates the excipients compatibility should be considered. The most suitable backing Laminates is the one with High flexibility.

3. Adhesive layer: This layer adheres the transdermal device on the surface of skin at proper site and position.

Ideal Properties of Adhesive Layer:

? It should have the ability to stick with minimum pressure.

? It should not interfere with the release rate of drugs.

? It should not affect the solubility of a drug.

? It should be non- irritant to the skin.

Release linear: These are the protective layers which are removed before the application of Transdermal patches on skin. They are helpful to prevent drug loss during storage and transportation conditions.

Introduction to Wound Healing: Wound is a term which means the damage or tearing of cells and its anatomy and cell function. Which is caused by various physical or thermal trauma. Skin wounds are typically of two types: acute and chronic. Acute wounds are traumatic or surgical wounds that usually heal overtime according to the normal healing process. Acute skin wounds vary from superficial scratches to deep wounds with the loss of tissues, damage to blood vessels. If the wound is large or injury is intense then there is an intensive response from the body to the wound. Acute wound healing is a complex process that is regulated by different types of cells and growth factors.

? Skin is the largest organ in the body and covers the body's entire external surface.

? It is made up of three layers, the epidermis, dermis and hypo-dermis. Skin's structure is made up of an intricate network that serves as thebody's initial barrier against pathogens, UV light and chemicals and mechanical injury and regulatestemperature and the amount of water released into the environment.

         
           
       
Fig No. 1: Overview of the Integumentary System (skin)

? Clean wound - made under sterile conditions where there are no organisms present and the skin is likely to heal without complications.

? Contaminated wound: usually resulting from accidental injury; there are pathogenic organisms and foreign bodies in the wound.

? Infected wound – the wound has pathogenic organisms present and multiplying, exhibiting clinical signs of infection (yellow appearance, soreness, redness, oozing pus).

? Colonized wound – a chronic situation, containing pathogenic organisms, difficult to heal (e.g. bedsore).

A skin wound results from the breakdown of the epidermal layer integrity

? Wound healing mostly means healing of the skin.

? Begins immediately after an injury to the epidermal layer and might take an years

? Dynamic process including highly organised cellular, humororal, and molecular mechanisms. ? It has three overlapping phases which are inflammation, proliferation and remodeling and its disruption leads to abnormal wand healing.

Types of Wound Healing Wound healing is classified as primary, secondary, and tertiary wound healing.

Primary Healing or Primary Intention

? Uncomplicated healing of a non-infected, well-approximated wound is defined as primary healing. e.g. Surgical wounds.

Secondary Healing or Secondary Intention

? If the wound healing course in this wound is disrupted by infection, dehiscence, hypoxia or immune dysfunction, the secondary healing stage begins.

? During secondary healing, granulation tissue formation and epithelization over this new tissue take place. These types of wounds are more susceptible to infections and poor healing.

Tertiary Healing or Third Intention

? It delayed primary wound healing after 4–6 days.

? This occurs when the process of secondary intention is intentionally interrupted and the wound is mechanically closed.

? This usually occurs after granulation tissue has formed.

Wound Healing Stages in Adults

Hemostasis Phase

The process of the wound being closed by clotting

? Happens very quickly.

? Starts when blood leaks out of the body, then blood vessels constrict to restrict the blood flow.

? The platelets aggregate and adhere to the sub-endothelial surface within seconds of the rupture of a blood vessel's epithelial wall.

? After that, the first fibrin strands begin to adhere in about sixty seconds.

? As the fibrin mesh begins, the blood is transformed from liquid to gel through procoagulants and the release of prothrombin.

? The formation of a thrombus or clot keeps the platelets and blood cells trapped in the wound area.

? The thrombus is generally important in the stages of wound healing but becomes a problem if it detaches from the vessel wall and goes through the circulatory system, possibly causing a stroke, pulmonary embolism or heart attack.

Inflammatory Phase

? Begins right after the injury when the injured blood vessels leak transudate (made of water, salt, and protein) causing localized swelling.

? Inflammation both controls bleeding and prevents infection.

? The fluid engorgement allows healing and repair cells to move to the site of the wound.

? During the inflammatory phase, damaged cells, pathogens, and bacteria are removed from the wound area.

? The white blood cells, growth factors, nutrients and enzymes create the swelling, heat, pain and redness commonly seen during this stage of wound healing.

? Inflammation is a natural part of the wound healing process and is only problematic if prolonged or excessive.

Proliferative Phase When the wound is rebuilt with new tissue made up of collagen and extracellular matrix

? The wound contracts as new tissues are built.

? A new network of blood vessels must be constructed so that the granulation tissue can be healthy and receive sufficient oxygen and nutrients.

? Myofibroblasts cause the wound to contract by gripping the wound edges and pulling them together using a mechanism similar to that of smooth muscle cells.

? In healthy stages of wound healing, granulation tissue is pink or red and uneven in texture. Healthy granulation tissue does not bleed easily.

? Dark granulation tissue can be a sign of infection, ischemia, or poor perfusion.

? Finally epithelial cells resurface the injury.

? Epithelialization happens faster when wounds are kept moist and hydrated.

Maturation Phase (Remodelling Stage)

? Collagen is remodelled from type III to type I and the wound fully closes.

? The cells that had been used to repair the wound but which are no longer needed are removed by apoptosis, or programmed cell death.

? The collagen laid down during the proliferative phase is disorganized and the wound is thick.

? Collagen is remodelled into a more organized structure along lines of stress, thereby increasing the tensile strength of the healing tissues. Fibroblasts secrete matrix metalloproteinases. The enzymes facilitate remodelling of type III collagen to type I collagen.

? Generally, remodelling begins about 21 days after an injury and can continue for a year or more.

? Even with cross-linking, healed wound areas continue to be weaker than uninjured skin, generally only having 80% of the tensile strength of unwounded skin.

       
           
       
  Fig No. 2: The wound healing process involves overlapping stages of bleeding, inflammation, proliferation, and remodeling (epithelialization).

The medicinal plants are widely used by the traditional medicinal practitioners for curing various diseases in their day to-day practice. In the traditional system of medicine, different parts (leaves, stem, flower, root, seeds and even whole plant) of Ocimum sanctum Linn. Have been recommended for the treatment of bronchitis, malaria, diarrhoea, skin disease and so on. The pharmacological studies reported in the present review confirm the therapeutic value of O. sanctum L.

       
           
       
Tulsi is an erect much branched shrub which is 30-60 cm tall with simple opposite green or purple leaves. Tulsi is also known as holy basil because it has pure energy. Tulsi has Ayurveda qualities like warming, clarifying, supporting lung health, supporting flow of life cycle, helps in circulation etc. Tulsi contains vitamin C & A also contains some minerals like calcium, zinc and iron

.

Tulsi also shows antioxidant property which is helpful in wound healing. Leaves of sanctum have anti-inflammatory, analgesic action. Flavonoids present in sanctum shows Anti lipoperoxidant action. Other therapeutic uses of sanctum:

1. Analgesic: It was reported that the oil extracted from tulsi plant possesses analgesic activity by inhibitory effect of acetylcholine, histamine and prostaglandin.

2. Anti-oxidant: it was reported that the leaves of this plant contain hydro alcoholic extract which is responsible for the antioxidant property.

3. Immunomodulatory: it was studied that leaves of O. sanctum increase the RBCs, WBCs, haemoglobin and antibodies production without affecting other biochemical activities when tested in mice.

4. Anti-inflammatory: The presence of fatty acids in the tulsi plant possesses anti-inflammatory activity. The main fatty acid responsible for the anti-inflammatory activity is linoleic acid which is capable of blocking the cyclooxygenase and lipoxygenase pathways

Procedure for preparation of plant extract

Turmeric is an herb plant that grows in India and Central America. Curcumin, the most active component of rhizome of curcuma longa L. has been studied for many years due to its bio-functional properties, especially antioxidant, radical scavenger, antimicrobial and anti-inflammatory activities, which play a crucial role in the wound healing process.

Curcumin has antioxidant, anti-inflammatory, antiviral and antifungal actions. Studies have shown that curcumin is not toxic to humans. Curcumin exerts anti-inflammatory activity by inhibition of a number of different molecules that play an important role in inflammation. Turmeric is effective in reducing post-surgical inflammation. Turmeric is also rich in vitamin C, vitamin B6, & other antioxidants that reduce the risk of serious health conditions like heart disease and diabetes. It is also an excellent source of manganese, iron. Other health benefits of turmeric:

1. Ease arthritis pain: curcumin contains anti-inflammatory properties, making it a potentially effective treatment for inflammatory conditions such as arthritis.

 2. Reduce depression symptoms: depression has been linked with lower levels of brain-derived neurotrophic factor (BDNF), a protein in the brain and spinal cord that regulates communication between nerve cells. Curcumin effectively increased levels of BDNF over the course of 10 days according to past research.

3. Contribute to treating diabetes: it’s also a promising treatment for inflammatory conditions, including diabetes. Curcumin may help prevent type2 diabetes by improving insulin resistance, lowering high blood sugar, and reducing high cholesterol.

4. Support skin health: turmeric is an anti-inflammatory, antimicrobial, and antioxidant rich spice, making it potentially effective for treating skin condition like acne, eczema and psoriasis

Procedure for preparation of curcumin from turmeric

Materials: Turmeric, Ethanol, Distilled water.

Instruments: Round bottom flask, Condenser, Inlet and Outlet of cold water, heating mental.

Filtration: Muslin cloth, Filter paper.

Glasswares: Beaker, Glass rod.

1. Ethanol 95% concentration of water in 100 ml.

2. Prepare turmeric paste by grinding method.

3. Add 10mg turmeric paste in 100 ml ethanol solution and mix.

4. Now pour the solution in a round bottom flask with the help of a funnel and the RBF placed on heating.

5. As the solution is ready for procedure, setup the condenser top of the round bottom flask (inlet at bottom and outlet top of the condenser for cold water).

6. Curcumin is sensitive to light so a sheet of aluminium foil is wrapped around just to keep away from light.

7. Turn on the heating mental and set the temperature 50°C centigrade for 2.5 hours.

8. Now using muslin cloth squeeze the solution then centrifuge the whole solution for 10 minutes at the RPM 3500.

9. Now pour the centrifuged solution into the beaker for filtration.

10. After filtration the solution is standing for 3 days.

11. After 3 days curcumin is extracted from turmeric.

Mechanism of Action

Aloe Vera is a succulent plant species of the genus Aloe. It originates from the Arabian Peninsula, but grows wild in tropical, semi-tropical, and arid climates around the world. It is a less or very short-stemmed plant growing to 60-100 cm (24-39 inches) tall, spreading by offsets. It is cultivated for commercial products, mainly as a topical treatment used over centuries. The leaves contains phytochemicals under study for possible bioactivity, such as lignans, phytosterols, polyphenols, acetylated mannans, polymannans, anthraquinoneC-glycoside, anthrones, and other anthraquinones, such as emodin and various lectins. There are many products containing aloe Vera’s acemannan, including skin lotion, cosmetics, ointments and gels for minor burns and skin abrasions, cold sores, rashes, wounds, frostbite, or dry skin.

Mechanism of Action

In traditional medicine, aloe Vera had been considered a healing plant acting to accelerate the closure rate of wounds. The mechanism of action of aloe vera on promoting wound healing has been extensively studied on experimental animals. Several hypotheses have been postulated for this crucial role in reducing pain, fighting inflammation, moisturizing the wound, qualitative and quantitative improvement in the collagen composition and increasing the migration of the wound’s neighbouring epithelial cells. The key regulator of the action of aloe Vera in promoting healing is the existence of a mannose-rich polysaccharide; called glucomannan which acts together with gibberellins and growth hormone stimulating fibroblasts to actively proliferate. Upon triggering fibroblast activation and proliferation, the collagen biogenesis significantly increases both quantitatively and qualitatively. The amount of collagen in wound area not only increases, but the transversal connections between bands also increase and other subtypes of collagen are created. Consequently, the wound area decreases and the healing process accelerates significantly.

Procedure for Aloe Vera Extract

1. The scaly leaves of Aloe vera were collected from the plant.

 2. Then washed using clean water.

3. Remove the spins.

4. Remove the top and bottom layer.

5. The covering was removed and the gel -like part was collected separately.

Procedure for formulation of Transdermal Patches

1. Weigh the required ingredients for the formulation.

2. Add 8 ml Chloroform and 4 ml methanol in the beaker and mix them properly using the electric stirrer or Magnetic stirrer.

3. Add 2.5 ml propylene glycol & 2.5 ml polyethylene glycol and again stir it continuously using an electric or magnetic stirrer.

4. Each medicinal plant extract i.e. 5 ml Tulsi extract, 5ml Aloe vera and 0.25 gm curcumin were added with constant stirring for 10-15 minutes.

5. Add 5 gm of HPMC at the time of interval 1 minute with constant stirring.

6. After the time period of 10-15 minutes when formulation becomes viscous then it is added to the glass Petri plate which are coated using the aluminium foil.

7. The Petri plate was placed in a Hot air oven at 50°C for a certain time for the evaporation of solvent.

       
           
       
Fig No. 4: Formulation of Transdermal Patches

Evaluation Test for prepared Transdermal patches

Various tests are performed for the evaluation of prepared Transdermal patches.

1. Organoleptics Characteristics

2. Surface Ph determination

3. Phytochemical Screening of Tulsi

4. Phytochemical Screening of Aloe vera

5. Phytochemical Screening of Curcumin

6. Measurements of thickness of patches % Moisture content

Organoleptics Characteristics: In this the organoleptic properties were studied like colour, odour texture.

? Color : The Colour of patches was evaluated to be Mustard.

? Texture: The texture of the formulated patches was evaluated to be smooth and uniform.

? Odour: The order of the formulated Patches was evaluated to be Herbal plants like.

1. Surface Ph determination: In this evaluation Test the Ph of the surface of Transdermal patches was evaluated using a Ph meter.

2. Phytochemical Screening of Tulsi: In phytochemical Screening of Tulsi extract the Chemical test named as Mayer's test, Ferric chloride test, killer kilani test, Benedict's test, Ninhydrin test were performed.

3. Phytochemical Screening of Aloe vera: In phytochemical Screening of Aloe vera extract the Chemical screening of Aloe vera extract the Chemical tests like Ferric chloride test, Mayer's test, Steroid test, Ninhydrin test were performed.

4. Phytochemical Screening of Curcumin: Mayer's test, Ferric chloride test, killer killani test, Ninhydrin test Benedict's test

5. Measurements of thickness of patches: The thickness of Formulated Transdermal Patches was Evaluated through Vernier Calliper.

6. % Moisture content: The % Moisture content was studied using Desiccator. Initially the individual patches were weighed and then kept in the Desiccator containing activated silica at room temperature for a time of 24 hours. Then afterwards the Patches were reweighed. %Moisture Content= [ initial weight - final weight] / initial weight*100.

RESULTS

Results of organoleptic Tests:

       
           
       
   Fig No. 4: Transdermal Patches

? Results of pH determination: The pH of Formulated Patches was found to be in Range of 5-9.

? Results for phytochemical Screening of Tulsi, Aloe vera and Curcumin.