INTRODUCTION:

TXA is a synthetic lysine derivative that was discovered in 1962 by Japanese scientists Shosuke and Okamoto¹. It is mainly employed as a fibrinolytic agent, inhibiting the conversion of plasminogen to plasmin, lowering prostaglandin and fibroblast growth factor synthesis, and as a result, decrease melanin synthesis. The effect of TXA in melasma was a serendipitous discovery by Nijo Sadako²in 1979. TXA can be administered orally, topically, intradermally, or by micro-needling³. The current oral dose for melasma is 250mg twice daily, which is much less than the 3900mg daily dose used to treat hemophilia, severe menstrual bleeding, or other hemorrhagic diseases⁴. In multiple studies, TXA has been shown to be effective in patients with melasma^5-7. TXA has a bioavailability of 30% to 50% when used orally. Hence topical delivery system could be a good alternative.

TXA is regarded as a pregnancy category B drug as no mutagenic activity has been detected in In vitro and in-vivo test systems. As it is only minimally excreted in breast milk, breastfeeding may be continued, if required^8.TXA is available in the market as a monotherapy or in a combination with other skin whitening agents in conventional dosage forms but it is not available alone in nano dosage form, hence a novel approach was made to incorporate TXA into nano ultra-deformable vesicles such as TEL to study its stability and effectiveness.

Formulations available^9,10

Tablets: Only TXA-250mg, 500mg; Combination of 250mg TXA with proanthocyanadin.

Injections: 100mg/Ml

Topical creams: (0.05g/50ml) in combination with whitening agents like kojic acid, mulberry extract, arbutin, vitamin E, etc.

A chronic, therapeutically challenging, universally relapsing hyperpigmentation disorder causing the appearance of brown or grey patches on the skin, primarily on the face called Melasma¹¹. It involves mainly the cheeks, chin, nose bridge, forehead, and commonly the upper lip³. Although melasma can occur in both sexes, races, and ethnicities, the overwhelming majority of the patients are women and individuals with Fitzpatrick’s skin types three to five which includes darker white skin, light brown, and brown skin, especially those who live in areas of intense UV radiation, including Hispanics, Asians, and African Americans¹². Melasma seems to be less common in men¹³. Affected individuals had emotional and psychological disruption, according to data from numerous quality-of-life studies¹⁴. Patients often feel irritated, humiliated, worried, and depressed about their skin appearance and suffer from significant emotional impact¹⁴. Etiological factors include intense exposure to sunlight, genetic predisposition, and hormonal imbalances¹⁵. Treatments approaches for melasma include UV protecting agents, topical skin lighteners, some newer oral and topical agents, chemical peeling agents, dermabrasion, and laser therapy¹⁵. All of these conventional creams, gels, and tablets have significant drawbacks, including low bioavailability, unpleasant taste, gastrointestinal side effects, and scarring. To overcome the drawbacks of conventional delivery systems, novel ultra-deformable vesicles (UDV) such as TEL have been developed, which have the advantage of being non-toxic, thermodynamically stable, and used as a tool for the delivery of large proteins and peptides¹⁶. TEL are composed of a phospholipid, ethanol, edge activator, and water. The use of ethanol and edge activators makes them extremely flexible, allowing them to easily cross the stratum corneum (SC). This novel dosage form uses less dose of TXA thus has the potential to have less toxicity and can increase patient compliance due to decreased dosing frequency.

The aim and objective of the present study were to enhance the skin permeation of TXA by incorporating it intoTEL.The developed TEL were optimized by central composite design methodology and evaluated for their characteristics such as Particle size (PS), entrapment efficiency (EE), skin deposition study, In vitro release study, and ex-vivo skin permeation studyinto the systemic circulation for 12 hours. The optimized TEL were incorporated into transdermal patch to improve patient compliance due to ease of application.

MATERIALS AND METHODS:

TXA was obtained as a gift sample from Hunan DongtingPharmaceutical Co. Ltd, China. Phospholipon 90G [Phosphotidylcholine(PC)] was a gift sample from Lipoid Ludwigshafen, Germany. Sodium cholate, Ethanol 99.8%, and Tween 80 were procured fromS.D. Fine chemicals, Mumbai. PEG 400 was obtained from BASF, India. HPMC K 15M was obtained from Chemtech speciality Pvt. Ltd. India. Distilled water used throughout the study was procured from J.K. Laboratories, Thane. All other chemicals and solvents used for the study were of analytical grade.

Preparation of TXA loaded TEL:

TXA-loaded TELs were prepared using the cold method¹⁷. This method is easy to scale up and can be used for both thermolabile and thermostable drugs¹⁸. In conical flask A, phospholipon 90G was dissolved in ethanol with constant stirring at 700rpm on a magnetic stirrer. TXA and Sodium cholate (edge activator) were dissolved in water in conical flask B, both the vessels were maintained at 30℃. Then the aqueous mixture B is added very slowly in ethanolic mixture A in a fine stream with constant stirring at 700rpm in a closed vessel. It was stirred for additional 5 min. The system was kept at 30℃ throughout the process. Size reduction was done by probe sonication (Oscar Ultrasonics, India) for five min at RT.

Optimization Of Txa Loaded Tel:

Experimental design^19,20

TXA-loaded TEL were optimized using Design Expert software, Version 12.0.7.0, Stat-Ease Inc, Minneapolis, MN. The response surface methodology was utilized, and the software created 13 different runs using central composite design, 2-factors, 5-level with five center points. To satisfy the statistical criterion of independent variables and to protect against the impacts of time-related factors, the run order was kept in a randomize mode.Required goals were to obtained the lowest PS and maximum E.E. Analysis of variance (ANOVA) and all statistical analysis were also carried out using the same software. Contour plot and 3-D surface graphs were used to investigate the relationship between different variables individually and in combined form respectively.

Characterization of Tel:

Determination of PS and Zeta potential:

The optimized batch was analyzed for PS by nanoparticle tracking analysis (NTA 3.1) using Nano sight NS500 with automated sample introduction, the computer-controlled motorized stage with CCD camera and red (638nm) laser.It works on the principle of dynamic light scattering through He-Ne laser having scattering angle of 90˚

The electrophoretic light scattering method was used to examine the optimized batch for Zeta potential. A current is applied across a pair of electrodes at either end of a cell containing the particle dispersion to measure the zeta potential. Particles get charged, get attracted to the oppositely charged electrode, and their velocities are measured. Stable formulations have zeta potential values that are not very close to 0 mV. For both PS and zeta potential measurement, approximately 0.2μL sample was diluted with 2mL of distilled water and results were obtained in triplicate^21,22

Microscopic morphology by scanning electron microscopy (SEM):

The Scanning Electron Microscopy (SEM) was used to determine the shape and morphology of the Transethosomes The TEL were directly mounted in SEM aluminum stub, using double-sided sticking tape and scanned in a low vacuum chamber with a focused electron beam at 20kV and magnification of 12,000X. Secondary electrons, emitted from the samples were detected as the image formed²³.

In vitro drug release study²⁴:

In vitro drug release was studied using Franz Diffusion cell. A cellophane dialysis membrane with a molecular weight cut off of 8000-12000 Dalton (Hi media) was hydrated with receptor medium phosphate buffer pH 5.8 overnight before being fastened between the donor and receptor compartments. The soaked membrane was clamped precautiously to the diffusion tube one end of 2 cm diameter (22.7cm²), which served as the donor compartment. Vesicular formulation of 4 ml of the TEL or 2*2cm of the transdermal patch was kept in the donor compartment. The receptor compartment was filled with 13 ml of Phosphate buffer pH 5.8 and stirred with a magnetic bead at 200-300rpm and the temperature of the system was maintained at 37±1℃ to mimic the human skin. The effective permeation area of the Franz diffusion cell was 2.60cm². At predetermined time intervals of 0, 1, 2, 3, 4, 5, 6, 7, and 12 hours, 1ml of aliquot was withdrawn and immediately replaced with an equal volume of fresh buffer. All samples were analyzed for TXA content by UV spectrophotometer at 567nm. The results were obtained in triplicates and the graph was plotted on Microsoft Excel between time and % cumulative release.

The release mechanism of the TXA can be explained through various kinetic models that wereapplied to In vitro release profile of the drug. In the current research, various release models; Korsmeyer Peppas²⁵, Higuchi²⁶, Hixon Crowell²⁷, first order²⁸, and zero order²⁹were applied on the release data of TXA from TEL

Ex-vivo skin permeation study:

Porcineabdomen skin was procured from the local slaughterhouse. The hair and subcutaneous fat adhering to the dermal side of the skin were removed from the upper portion of the skin surface. Because of its similar lipid content and permeability to human skin, porcine abdomen skin was used as a model membrane for skin permeation study. The sample of the was placed between the donor and receptor compartments of the diffusion cell. The dorsal surface of the skin was placed in contact with the donor chamber which was filled with 4 ml of the TEL or 2*2 cm of the transdermal patch. The receptor compartment was filled with 13ml of Phosphate buffer pH 5.8 and stirred with a magnetic bead at 200-300rpm and the temperature of the system was maintained at 37±1℃ to mimic the human skin. The Franz diffusion cell had an effective permeation area of 2.60 cm². 1ml of aliquot was withdrawn at predetermined time intervals of 0, 1, 2, 3, 4, 5, 6, 7, and 12hrs respectively, and was immediately replaced with an equal volume of fresh buffer. All samples were analyzed for TXA content by UV spectrophotometer at 567nm and the %cumulative release of drug was plotted against a function of time.

Permeation data analysis:

The steady state flux (J ug cm^-2 hr^-1 ) was calculated from the slope of linear portion of the plot divided by the skin surface area. The steady state permeability coefficient (Kp) of the drug through porcine skin was calculated by using the following equation:

Kp= J/Co

Where, J is the flux and Co is the concentration of TXA in the TEL formulation.

Skin deposition studies³⁰

The skin's surface was cleansed five times with distilled water at the end of the permeation experiment to eliminate excess TXA from the skin's surface. The skin was then chopped into little pieces and homogenized with distilled water. The resultant solution was then centrifuged at 15,000 rpm for 15 minutes. The supernatant was then separated and the TXA content was determined using a UV spectrophotometer set to 576 nm.

RESULTS AND DISCUSSION:

Experimental design²⁰:

Quality by design is very popular tool in saving time and cost³¹. The central composite design technique was used with 2 factors and 5 different levels. Thirteen runs were generated by Design Expert software based on the selected range of lipoid and surfactant and were further evaluated according to the responses, namely PS and EE. (Table 1) shows different concentrations of independent variables such as phospholipon 90G and sodium cholate, as well as their responses such as PS and EE. Run number 7 was chosen by software based on the goal of having the smallest size of nanoparticles and the highest E.E.

Factor A- Phospholipid concentration

Phospholipid concentration was varied to study the effect of phospholipid concentration on PS and %EE.

Levels of factor A are shown in (Table 2).

Factor B- Surfactant concentration

Surfactant concentration was varied to study the effect of surfactant concentration on PS and %EE.

Levels of factor B are shown in (Table 2).

The optimized batch no 7 gives best results and the formula is depicted in (Table 3).

Table 1: Design matrix and responses

Std	Run	Factor 1 A: Amt of Phospholipid	Factor 2 B: Amt of surfactant	Response 1 Avg Particle size	Response 2 Entrapment efficiency
12	1	600	60	152	83
10	2	600	40	94	84
3	3	400	80	63	58
13	4	600	60	152	83
7	5	600	31.71	312	65
8	6	600	88.28	78	76
11	7	600	40	72	94
5	8	317.15	60	59	59
2	9	800	40	574	79
1	10	400	40	52	69
9	11	600	60	101	89
6	12	800	60	210	90
4	13	800	80	225	85

Table 2: Variables selected for optimization

variables	Low (-1)	Medium (0)	High (1)
Amount of Phospholipid	400 mg	600 mg	800 mg
Amount of Surfactant	40 mg	60 mg	80 mg

Table 3:Formula for optimized batch of TEL (Batch no 7)

Ingredients	Quantity
Tranexamic acid	250 mg
Phospholipon 90G	600 mg
Sodium cholate	40 mg
Ethanol	30%
Water	Upto 20 ml

Statistical significance of PS:

In the 3-D response surface plot (Fig.1a) and contour plot (Fig. 1b), the particle size of all thirteen formulations is represented. PS reduces at first with lower lipid concentrations and subsequently increases with increasing concentrations. The optimal amount of surfactant, 40mg, and lipoid, 600mg, produces the optimal PS. PS can fluctuate as the concentration of lipoid and surfactant increased or decreased. Comparable trends were reported of similar pattern²⁰.

Fig 1a: Response Surface plot for PS

Fig 1b: Contour plot for PS

Statistical significance of EE:

The EE of each of the thirteen formulations is depicted in a 3-D response surface plot (Fig.2a) and a contour plot (Fig. 2b). Initially, there is an increase in EE with increasing lipid content up to an optimum level, which could be attributable to an increase in vesicle size due to increased drug incorporation. Increased surfactant levels cause a drop in E.E, which could be attributed to pore development on the phospholipid bilayer. Sodium cholate solubilizes and holds the drug in the lipid bilayer, thus increasing E.E. Comparable trends were reported of similar pattern³².

Fig 2a: Response surface plots for EE

Fig 2b: contour plot for E.E

Characterization Of Tel

PS and Zeta potential:

The average particle size was found to be 72nm as shown in (Fig 3a). The zeta potential of the optimized batch shown in (Fig 3b) was found to be -16.4mV which was in good agreement in literature due to the net charge of the lipid composition in the formulation. Under experimental condition pH 5.8, Phospholipon carried a net negative charge. The edge activators used were anionic in nature. Therefore a net negative charge in all formulation was observed. Also, the negatively charged liposome formulation strongly improved skin permeation of drugs in Transdermal delivery³³. The skin also has a slight negative charge. Therefore, the negative zeta potential of the optimized TEL containing TXA might cause little influence in improved drugpermeation through porcine skin due to electrostatic repulsion between the same charge of the skin surface and the TEL^34,35.

Fig 3a: Particle size of optimized batch (Batch no 7)

Fig 3b : Zeta potential of optimized batch(Batch no 7)

Scanning electron microscopy (SEM):

SEM was used to provide information on the morphology and sizes of the particles. It also confirmed the formation of lipid vesicles. (Figure 3c) depicts a spherical and uniform particle distribution with no aggregates. The size of all particles is similar, indicating that the system is well dispersed. The nanoparticles ranged in size from 0 to 100nm.

Fig 3c: SEM images of optimized batch of TEL (Batch no 7)

In vitro drug release study^36,37

The diffusion studies were carried out in non-occlusive conditions at skin pH (Phosphate Buffer pH 5.8) to allow the driving force provided by the osmotic gradient TXA encapsulation in TEL resulted in a significant prolongation in TXA release across the artificial membrane. According to the above results, TEL dispersion and patch release more drug than conventional formulation. High permeation of TEL may be due to a combination of both ethanol and edge activators. The release profile of the patch indicates slow release as compared to TEL dispersion. This is explained by the fact that drug diffusion from the TEL carrier was followed by diffusion from the patch matrix, resulting in sustained release effects. The lower cumulative release of the plain drug solution can be attributed to its lower solubility. Different models were applied like KorsmeyerPeppas²⁵, Higuchi²⁶, Hixon Crowell²⁷, first order²⁸, and zero order²⁹to know the mechanism of drug release from nanoparticles. The best fit model was found to be KorsmeyerPeppas model having R²value 0.9756.Observed sustained release effect was in the order of TEL patch > TEL dispersion > Marketed formulation > Plain drug solution as shown in (Fig 4a).The improved release of TEL formulation in comparison to plain drug solution can be conventionally attributed to drug: lipid ratio¹⁷.The release from the TEL patch, TEL dispersion, Marketed formulation, and plain drug was found to be 85.81%, 78.65 %, 72.54%, and 53.54% respectively.

Fig 4a: In vitro drug release from [A] TXA patch [B] TEL dispersion [C] Marketed formulation [D] Plain drug

Ex-vivo skin permeation study³⁸:

The ex-vivo skin permeation studies provide information about the product behavior pattern in-vivo since they indicate the amount of drug available for absorption. The plain drug solution showed minimum skin permeability having a flux 7.25μg/ cm² /h while TXA patch, TEL dispersion and marketed formulation showed flux of 35.14 μg/cm² /h, 32.85 μg/ cm² /h, and 19.54μg/ cm² /h respectively. The % cumulative release in 12 hrs was found to be 87.53%, 80.1%, 73.81%, 62.54% for TXA patch, TEL dispersion, 5% Akira marketed cream and plain drug solution respectively as shown in (Fig 4b). Ethanol provides the flexibility to phospholipid vesicles as well as fluidized the SC lipids, allow the vesicles to squeeze themselves from the stratum corneum and hence enhance the penetration of the drug. Both in vitro and Ex vivo release patterns were almost similar.

Fig 4b : Ex vivo drug release from [A] TXA patch [B] TEL dispersion [C] Marketed formulation [D] Plain drug sol.

Skin permeation analysis:

The permeability coefficient of the TEL patch was found to be 3 fold and that of TEL dispersion was found to be 2 fold as compared to the marketed formulation as shown in (Table 4).

Table 4: Skin permeation data

Formulations	Flux [μg/cm² /h]	Permeability coefficient (x10^-3)[cm hr-1]
TEL patch	35.14	8.95
TEL dispersion	32.85	7.42
Marketed formulation	19.54	3.158
Plain drug solution	7.25	0.327

Skin deposition study:

TXA skin deposition from various formulations is depicted in (Fig 4). The amount of TXA retained from the TEL patch and TEL dispersion was found to be 11% and 9.2 %, respectively, which was much higher than the marketed formulation and plain drug solution, which were 7% and 2.5%, respectively. The combined effect of phospholipid, ethanol, and edge activator resulted in increased skin deposition and improved dispersion of the TEL patch.

Fig 4: Skin deposition study of TXA from various formulations

CONCLUSION:

TEL loaded with TXA were successfully developed and incorporated into the transdermal patch. Permeation enhancers and edge activators were used to improve transdermal drug delivery. The successful identification of critical parameters important for PS and EE was accomplished through the design of expert software. Release, permeation,and skin deposition studies concluded the accomplishment of the transdermal patch to efficiently and significantly transport the nano-carrier into the systemic circulation. This concludes that TEL can be a potential carrier for the delivery of TXA and other similar drugs.

CONFLICT OF INTEREST:

There is no conflict to declare.

REFERENCES:

1. Grimes PE, et al. New oral and topical approaches for the treatment of melasma. International Journal of Women's Dermatology. 2018 Nov 20;5(1):30-36.doi:10.1016/j.ijwd.2018.09.004.

2. George A. Tranexamic acid: An emerging depigmenting agent. Pigment Int 2016;3(2): 66–71.doi: 10.4103/2349-5847.196295.

3. Taraz M, et al. Tranexamic acid in treatment of melasma: A comprehensive review of clinical studies. Dermatol Ther 2017;30(3): e12465.doi:10.1111/dth.12465

4. Cai J, et al. The many roles of tranexamic acid: An overview of the clinical indications for TXA in medical and surgical patients. European journal of haematology 2020; 104(2): 79-87.doi:10.1111/ejh.13348.

5. Sheu SL. Treatment of melasma using tranexamic acid: what's known and what's next. Cutis 2018;101(2):E7–E8.

6. Xu Y, et al. Efficacy of functional microarray of microneedles combined with topical tranexamic acid for melasma: A randomized, self-controlled, split-face study. Medicine (Baltimore) 2017; 96(19): e6897.doi:10.1097%2FMD.0000000000006897

7. Del Rosario, et al. Randomized, placebo-controlled, double-blind study of oral tranexamic acid in the treatment of moderate-to-severe melasma. Journal of the American Academy of Dermatology 2018; 78(2): 363-369.doi:10.1016/j.jaad.2017.09.053

8. Kaur A, et al. Tranexamic acid in melasma: a review. Pigment Int 2020;7(1):12-25.doi: 10.4103/Pigmentinternational.Pigmentinternational_

9. Tan AWM, et al. Oral tranexamic acid lightens refractory melasma. Australas J Dermatol 2017;58(3):e105-e108.doi:10.1111/ajd.12474.

10. Zhang L, et al. Tranexamic acid for adults with melasma: a systematic review and meta-analysis. BioMed research international 2018; doi:10.1155/2018/1683414.

11. Grimes PE., et al. New oral and topical approaches for the treatment of melasma. International Journal of Women’s Dermatology 2018; 5(1): 30–36.doi:10.1016/j.ijwd.2018.09.004.

12. Rodrigues M, Pandya A. Melasma: Clinical diagnosis and management options. Australas J Dermatol 2015;56(3):151–63.doi:10.1111/ajd.12290.

13. Sarkar R., et al. Melasma in men: A review of clinical, etiological, and management issues. The Journal of clinical and aesthetic dermatology 2018 11(2), p.53-59.

14. Ikino JK, et al. Melasma and assessment of the quality of life in Brazilian women. An Bras Dermatol 2015;90(2):196–200.doi:10.1590/abd1806-4841.20152771

15. Aishwarya K, et al. Current concepts in melasma - A review article. J Skin Sex Transm Dis 2020;2(1):13-17.doi: 10.25259/JSSTD_34_2019

16. Sandeep Gupta, Dheeraj Ahirwar, Neeraj K Sharma, DeenanathJhade. Proniosomal Gel as a Carrier for Improved Transdermal Delivery of Griseofulvin: Preparation and In vitro Characterization. Research J. Pharma. Dosage Forms and Tech. 2009; 1(1): 33-37.

17. Pawar P et als. Different Techniques for Preparation of Nanosuspension with Reference to its Characterisation and various Applications - A Review. Asian J. Res. Pharm. Sci. 2018; 8(4): 210-216. doi: 10.5958/2231-5659.2018.00035.8

18. Bajaj KJ, et al. Nano-transethosomes: A Novel Tool for Drug Delivery through Skin. Indian J of Pharmaceutical Education and Research 2021;55 Suppl 1:1-10.doi: 10.5530/ijper.55.1s.33.

19. Gondkar SB, et al. Formulation Development and Characterization of Etodolac Loaded Transethosomes for Transdermal Delivery. Research J. Pharm. And Tech. 2017; 10(9):3049-3057. doi:10.5958/0974-360X2017.00541.8.

20. Phatak Atul A., Chaudhari Praveen D. Development and Evaluation of Nanogel as a Carrier for Transdermal Delivery of Aceclofenac. Asian J. Pharm. Tech, 2012; 2(4): 125-132.

21. Kumara Swamy S, Ramesh Alli. Preparation, Characterization and Optimization of Irbesartan Loaded Solid Lipid Nanoparticles for Oral Delivery. Asian Journal of Pharmacy and Technology. 2021; 11(2):97-4. doi: 10.52711/2231-5713.2021.00016

22. Honary S, Zahir F. Effect of zeta potential on the properties of nano-drug delivery systems-a review (Part 1). Trop J Pharm Res. 2013;12(2):255-64.doi:10.4314/tjpr.v12i2.19.

23. Jessy Shaji, Monika Kumbhar. Linezolid Loaded Biodegradable Polymeric Nanoparticles Formulation and Characterization. Res. J. Pharm. Dosage Form. & Tech. 2018; 10(4): 272-278. doi: 10.5958/0975-4377.2018.00040.X

24. Varshosaz, J, et al. Lipid Nanocapsule-Based Gels for Enhancement of transdermal Delivery of Ketorolac Tromethamine. J. Drug Deliv. 2011,2011, 1-7.doi: 10.1155/2011/571272.

25. Wu IY, et al. Interpreting non-linear drug diffusion data: Utilizing Korsmeyer-Peppas model to study drug release from liposomes. Eur J Pharm Sci. 2019 October 1;138: 105026.doi: 10.1016/j.ejps.2019.105026.

26. D.R. Paul. Elaborations on the Higuchi model for drug delivery. Int J Pharm. 2011;418:13-17. doi:10.1016/j.ijpharm.2010.10.037.

27. Rehman Q, et al. Role of Kinetic Models in Drug Stability. In: Akash M.S.H., Rehman K. (eds).Drug Stability and Chemical Kinetics. Springer, Singapore.2020 Nov 02;155-165.doi:10.1007/978-981-15-6426-0_11.

28. Singhvi G, Singh M. In vitro drug release characterization models. Int J Pharm Stud Res. 2011;2:77-84.

29. Yang Z, et al. Design of a zero-order sustained release PLGA microspheres for palonosetron hydrochloride with high encapsulation efficiency. Int. J. Pharm. 2020:119006. doi:10.1016/j.ijpharm.2019.119006.

30. Shaji J, Garude S. Transethosomes and Ethosomes for Enhanced Transdermal Delivery of Ketorolac Tromethamine : A Comparative Assessment. International Journal of Current Pharmaceutical Research. 2014;6(4):88 - 93.

31. Vinod K.R., Sandhya S. Factorial Designing for Pharmaceutical Product and Process Development. Research J. Pharma. Dosage Forms and Tech. 2011; 3(5): 199-202.

32. Tipre DN, Vavia PR. Formulation optimization and stability study of transdermal therapeutic system of nicorandil. Pharm. Dev. Technol. 2002;7:325–32.doi:10.1081/PDT-120005729.

33. Sinico, C, et al. Liposomes as carriers for dermal delivery of tretinoin: in vitro evaluation of drug permeation and vesicle–skin interaction. Journal of Controlled Release 2005;103(1):123–136.doi:10.1016/j.jconrel.2004.11.020.

34. K.Vijaya S et al. Formulation and Evaluation of Rutin Loaded Nanosponges. Asian J. Res. Pharm. Sci. 2018; 8(1):21-24. doi: 10.5958/2231-5659.2018.00005.X

35. Shaji, J., and S. Garude. “Transethosomes and Ethosomes FOR enhanced Transdermal Delivery of Ketorolac Tromethamine: A Comparative Assessment”. International Journal of Current Pharmaceutical Research 2014;6(4):88-93.

36. Talib S, et al. Chitosan-chondroitin based artemether loaded nanoparticles for transdermal drug delivery system. Journal of Drug Delivery Science and Technology 2021; 61: p.102281.doi:10.1016/j.jddst.2020.102281.

37. Saraswathi B et al. Formulation and Characterization of Tramadol HCl Transdermal Patch. Asian J. Pharm. Tech. 2018; 8 (1):23-28 . doi: 10.5958/2231-5713.2018.00004.1

38. Salve P et al. Formulation and Evaluation of Solid Lipid Nanoparticle Based Transdermal Drug Delivery System for Alzheimer’s Disease. Res. J. Pharm. Dosage Form. and Tech. 2016; 8(2):73-80. doi: 10.5958/0975-4377.2016.00011.2

Received on 01.07.2021 Modified on 24.03.2022

Research J. Pharm. and Tech 2023; 16(4):1549-1555.

DOI: 10.52711/0974-360X.2023.00253