QIS College of Pharmacy, Ongole
A naturally developed polyphenol found among Curcuma longa, curcumin has potent anti-inflammatory, antioxidant, antibacterial, and anti-fibrotic qualities. However, because of its high first-pass metabolism, low bio availability, and poor solubility, its therapeutic application is limited. A dual-action, fast-dissolving mucoadhesive oral film was created to get around these restrictions by treating the oral mucosa locally and delivering medication systemically by transmucosal absorption¹.Incorporating curcumin nanoparticulates or complexes into the film, in along with hydroxypropyl methyl cellulose (HPMC) and herbal plasticizers, improved solubility and permeability. A neutral surface pH, suitable tensile strength, homogeneous drug distribution, and quick disintegration within 60 seconds were all shown by physicochemical analyses. Studies on in vitro release verified a 4- to 6-hour sustained release profile, indicating extended therapeutic action².Pilot clinical trials and preclinical pharmacological evaluations shown notable local advantages, such as decreased oral inflammation, quicker wound healing, and symptomatic alleviation in Oral sub-mucous fibrosis (OSMF). Because buccal absorption is effective and avoids hepatic metabolism, systemic effects were also noted, including decreased oxidative stress and inflammatory indicators³.When it comes to treating oral lesions, chronic inflammatory disorders, and systemic conditions where curcumin's clinical efficacy is limited by inadequate bioavailability, this dual-action oral film shows promise. It provides a new, patient-friendly method to enhance the delivery of curcumin, achieving both localized and systemic therapeutic benefits?.
The rhizomes of Curcuma longa, or turmeric, contain a polyphenolic chemical called curcumin, which has been well known for its wide range of pharmacological properties, such as anti-inflammatory, antioxidant, antibacterial, wound-healing, and anticancer properties. Its capacity to alter numerous molecular targets and Signaling pathways gives it pleiotropic therapeutic potential, which makes it a desirable option for the treatment of a range of acute and chronic illnesses. Apart from its conventional applications in Chinese and Ayurvedic medicine, curcumin has drawn a lot of interest in contemporary pharmaceutics as a safe bioactive substance that comes from nature1.
Curcumin's clinical application is limited by its low oral bioavailability, rapid metabolism, and poor water solubility, despite its potential therapeutic profile.
Traditional dose forms frequently struggle to achieve and sustain therapeutic plasma concentrations, necessitating the development of new delivery methods to enhance its solubility, stability, and absorption.
Among these methods, herbal oral films provide a new, patient-friendly way to administer curcumin. Oral films can be directly absorbed via the mouth mucosa without undergoing a significant amount of first-pass metabolism since they are thin, flexible polymeric strips that degrade rapidly when they come into direct contact with saliva.This increases patient compliance in addition to bioavailability, especially in the elderly and pediatric populations².
Fig: 1
By reducing potential toxicity and producing synergistic pharmacological advantages, the addition of natural polymers and herbal excipients to oral film formulation significantly enhances curcumin's medicinal performance.
In diseases including oral submucous fibrosis (OSMF), oral inflammatory disorders, and oxidative stress-related pathologies, where local and systemic curcumin administration may be helpful, such formulations are especially pertinent³.
The objective of this work is to formulate and evaluate curcumin-loaded herbal oral films in order to maximize their physicochemical properties, mechanical strength, disintegration time, and drug release profile.
The produced films will also be evaluated for their capacity to improve curcumin's bioavailability and solubility, thereby resolving its traditional delivery issues?.
The natural polyphenolic chemical curcumin, which is extracted from the turmeric plant Curcuma longa, has a wide range of pharmacological properties, such as anti-inflammatory, anti-microbial, wound-healing, and anticancer properties. Due to its poor water solubility, rapid metabolism, and low oral bioavailability, curcumin's clinical application is limited despite its wide medicinal potential.
By promoting quick release and absorption through the oral mucosa, curcumin can be added to oral film formulations to improve its solubility, stability, and therapeutic effectiveness. Additionally, there are synergistic benefits to the dual-action herbal oral film idea, which curcumin with another herbal bioactive substance. Curcumin's pharmacological profile can be enhanced by herbal extracts like Glycyrrhiza glabra (licorice) , which is well-known for its anti-ulcer, antibacterial, and calming qualities. In addition to addressing several therapeutic goals at once, this combination improves patient acceptability by offering safe, natural, and efficient therapy alternatives5.
Thus, developing and testing dual herbal oral films based on curcumin offers a fresh way to enhance medication administration, boost bioavailability, and capitalize on the complementary qualities of organic substances. The creation of patient-friendly, quick-acting, and multipurpose therapeutic systems that can be used to treat a range of illnesses appears to be possible using this approach.
MATERIALS AND METHODS :
Title
Formulation and Assessment of Dual-Action Herbal Oral Films Based on Curcumin (Anti-inflammatory + Antimicrobial via Clove Oil)
Actives: (≥95% curcuminoids, HPLC) Curcumin. clove oil (COA-verified; 80–85% w/w eugenol)6.
Polymers & excipients:
(film former) PVA 88% hydrolysed, poly (vinyl alcohol). hydroxypropyl methylcellulose (HPMC E15) (disintegration control/co-film forming). Glycerol (pharm. grade plasticizer). Curcumin is dissolved by hydroxypropyl-β-cyclodextrin (HP-β-CD). Tween-80 (polysorbate-80) is an emulsifier and surfactant. A preservative that is optional, potassium sorbate is 0.1% w/w of dry polymer. It contains food-grade peppermint flavour and optional menthol crystals (≤0.05% w/w of wet cast)7.
Solvents and media:
Purified water and 96% ethanol. pH 6.8 phosphate buffer (saliva-like). If sink conditions for dissolution are necessary, add 0.5% w/v of SLS to the buffer8.
Microbiology: Staphylococcus aureus and Streptococcus mutans (or P. gingivalis if an anaerobic solution is available). Mueller-Hinton broth or agar, with anaerobic additions as necessary. Fresh pig buccal mucosa from an abattoir or commercial buccal membrane (ex vivo) is optional9.
Fig :2
Equipment :
Magnetic stirrer, bath sonicator, and high-shear homogenizer (10–15 krpm). probe sonicator, vacuum desiccator, and hot-air/tray dryer (40–45 °C). An adjustable applicator was used to level the glass and acrylic casting plates (wet gap 300–500 μm). digital micro meter, texture analyser (tensile grips), and pH meter. A UV-Vis spectrophotometer, HPLC-UV (C18). USP Apparatus II is a dissolution tester that works well with small amounts10.
Fig :3 Film prepared
Suitable mixture of solvents to this excipients are added
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Heated upto 60°C and stirred at 1000rpm and forms Solution
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Add polymer and cooled to room temperature and stirred at 1000rgum
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Add API and allowed for evaporation of solvent
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Final Film Solution is defourmed and casted and dried at 60°C
Study design & target product profile (TPP) :
Buccal films that dissolve quickly and provide 10 mg of curcumin per strip together with clove oil, which is equivalent to about 2 mg of eugenol per strip, they disintegrate in less than 60 seconds, have a pH of 6.0 to 7.0 on the surface, taste well, are mechanically sound for handling. and have antibacterial activity against oral infection11.
Fig :4 Health benefits.
Pre formulation:
1. Curcumin solubilization (HP-B-CD inclusion, aqueous)
Dissolve HP-B-CD in water at 55-60°C (10% w/v), Make a stock with 10 mg/ml. of curcumin in ethanol. In HP-B-CD. add curcumin stock dropwise (molar ratio HP-B-CD: curcumin = 2:1), stir for 60 min. Extract ethanol at 40 °C with reduced pressure, then add water to the mixture to get a clear12.
2. Clove oil nano emulsion (cold emulsification)
Combine Tween-80 and clove oil (oil: surfactant 1:1.5 w/w). Add premix to warm water (45 °C) to 1-2% w/w oil in the pre-emulsion while under high shear (12,000 rpm, 5 min). Use an ice bath to probe-sonicate at 30% amplitude for 2×60 s at 60-second intervals13.
Film formulation (solvent casting):
3. Polymer base
PVA and HPMC E15 should be dissolved in water to give the total polymer 4% w/w at a 60:40 (PVA:HPMC, w/w) ratio. Stir until completely hydrated (overnight, ambient). Include glycerol at 25% w/w of the total polymer, 0.05 w/w of xylitol (wet basis), 0.25% w/w of citric acid (wet), and, if applicable, 0.1% of potassium sorbate of the dry polymer. For 20 minutes, mix without foaming14.
4. Drug loading & final mix
To reach the desired dosage, add curcumin-1C to the polymer base (see to the Dose Calculator below), rinse the stock beaker to reduce loss. Slowly add the clove oil nanoemulsion while stirring, and keep going for another 20 minutes. To release trapped air, degas under a light vacuurn or leave it for 30 minutes.
5. Casting, drying, and conditioning
Level the casting plate; to achieve a dry thickness of approximately 100-130 µm, set the applicator to 300-400 µm wet gap. Cast a known mass per unit area; let it cure for 8-12 hours (or at room temperature for 24-36 hours) until it is not sticky; shield it from the sun. Peel the films and place them in a desiccator for 24 hours at 25 °C-60% relative humidity15.
6. Cutting & packaging
Cut strips to the specified size, or 2 x 3 cm (6 cm²). Stow the desiccant in heat-sealed sachets that are protected from light.
7. Physicochemical characterization :
Appearance and uniformity: Visual examination for air bubbles, phase separation, and clarity under white or UV light ..Digital micrometre (n 10 at various locations) for thickness.. Weight homogeneity: 20 individual strips, give mean SD. Folding endurance: Folding by hand until it ruptures (n=10)16.
8. Disintegration & in-vitro dissolution
In-mouth disintegration model: 10 ml. of pH 6.8 buffer, 370.5 °C, mild stirring; breakup time (n=6) 500 ml. of pH 6.8 buffer at 37 °C and 50 rpm is the drug release method (USP-II); if necessary, use 0.5% SLS. Take a sample with media substitution at 2, 5, 10, 15, 20, and 30 minutes. To stop film from floating, secure it to a glass slide17.
Fig :5
Assay:
Curcumin: HPLC-UV (C18, 425 nm) or UV-Vis at 425 nm (check specificity with placebo extract); mobile phase: acetonitrile: water (60:40) with 0.1% acid, 1.0 ml./min..
Clove oil (eugenol): GC-FID or HPLC-UV 280 nm, if available.
9. Content uniformity
Single strips for assay (n=10). Acceptance: RSD ≤6%; 85-115% of label claim18.
10. Mucoadhesion & residence (recommended):
Porcine buccal mucosa on a texture analyzer probe: mucoadhesive strength; record detachment force (g or N) (n=6).Mucosa placed in a 50 ml. pH 6.8 beaker at 37 °C for the duration of the in-vitro residence period is allowed to detach with light agitation.
11. Permeation (optional)
Bacal mucosa in Franz cells. Receptor: PBS pH 7.4+0.5% SLS, 37 "C: donor: hydrated strip. Curcumin is analyzed by HPLC to meaure flux (J) and permeability (Papp) in samples 0-6 hours19.
12. Antimicrobial activity (endpoint of dual action)
One-strip equivalent should be dissolved in a minimum ethanol:water (1:9) solution for agar diffusion. Put dises or wells onto Mueller-Hinton agar that has been infected. For 24 hours, incubate at 37 °C (anaerobic for P. gingivalis, aerobic for S. mutans/S. aureus). Measure the inhibitory zones in millimeters.
MIC/MBC (broth microdilution): serially dilute strip extract; include positive control chlorhexidine or eugenol standard; include placebo film, curcumin-only, and clove-oil-only controls.
13. In-vitro anti-inflammatory proxy
Use strip extracts to stabilize the RBC membrane and/or prevent protein denaturation (egg albumin or BSA); show the percentage of inhibition and ICs in comparison to the curcumin standard.
Fig:6
14. Research on stability
As per ICH QIA(R2), store the strips in moisture-barrier sachets with desiccant at 25 °C/60% RH and 40 °C/75% RH for one and three months, respectively. At 15 minutes, assess the look, thickness, disintegration, content (eugenol/curcumin), and percentage release. Acceptance: assay 90-110%; no significant variation (ANOVA. p>0.05)20.
Fig: 7 Stucture
Experimental design & statistics
A Box-Behnken design with three factors and three levels was used.
Responses:
Disintegration time (DT), tensile strength (TS), 15-min% release (Q15), mucoadhesive detachment force (MDF). Model by multiple regression with interaction terms; desirability function targets DT 60s, Q15 ≥80%, TS 20-40 MPa, MDF adequate for handling. Confirmatory checkpoint batches prepared at predicted optimum. Data as mean SD; group comparisons by one-way ANOVA with Tukey (α=0.05).
Notes for adaptation:
Utilize a different polymer system (such as sodium alginate HPMC or pullulan/HPMC) by adjusting the glycerol to 20-30% of the polymer while maintaining a 3-5% w/w total polymer. Curcumin alone, without cyclodextrin, in a nanoemulsion is acceptable: Curcumin should be dissolved in ethanol:PEG-400 (1:1), then emulsified with Tween-80 or Poloxamer 188 to achieve clarity. I'll turn your goal strip size, per-strip dosages, and plate measurements into a master formula table with batch weights and volumes as well as a one-page SOP if you share them with me21.
Fig :8 oral film.
CONCLUSION:
The current review emphasizes that by addressing issues such poor solubility, limited bioavailability, unpleasant taste, and drug instability, the Development and evaluation of curcumin-based and dual-action herbal oral films offer a promising substitute for traditional dosage forms. Curcumin's synergistic antioxidant, anti-inflammatory, and antibacterial properties are enhanced when combined with complementary herbal extracts, such as Glycyrrhiza glabra and Ocimum sanctum, in oral films. Rapid disintegration, enhanced patient compliance, and site-specific medication release are all guaranteed by the film-based approach, which also lessens the negative side effects of synthetic pharmaceuticals.
Evaluation tests verify that, depending on the intended therapeutic application, optimized formulations exhibit desirable mechanical strength, homogeneity, sustained or immediate release patterns, and satisfactory physicochemical qualities. Apart from improving the solubility and bioavailability of phytochemicals, the dual herbal approach targets multiple therapeutic targets, particularly in the treatment of inflammatory and viral oral disorders.
Curcumin and dual herbal oral films, taken together, offer a new and versatile drug delivery system that may include natural bio actives into efficient, patient-friendly dose forms. Large-scale clinical validation, stability testing, and investigation of sophisticated nanocarrier systems should be the focus of future research in order to increase their therapeutic efficacy and position them as trustworthy substitutes in contemporary pharmacies22.
REFERENCES
Dr. M. Kishore Babu, S. Gowthami, A. Venkata Vineesha, Ch. Anusha, J. Madankumar, A. Vyshnavi, M. Sai Sri Bhavana, Formulaton and Evaluation of Curcustrips and Dual Action of Herbal Oral Film, Int. J. of Pharm. Sci., 2025, Vol 3, Issue 10, 2487-2495. https://doi.org/10.5281/zenodo.17433532
10.5281/zenodo.17433532
