preparation and characterization of monobenzone gel ...

Vol 5 | Issue 3 | 2015 | 119-125. e-ISSN 2249 – 7706 print-ISSN 2249– 7714

International Journal of

Advanced Pharmaceutics www.ijapjournal.com

PREPARATION AND CHARACTERIZATION OF MONOBENZONE GEL LOADED SOLID LIPID NANOPARTICLES B. Venkateswara Reddy*, K. Navaneetha Department of Pharmaceutics, St.Pauls College of Pharmacy, Turkayamjal (V), Hayathnagar (M), R.R.Dist-501510, India. ABSTRACT In the present research work, topical gel composed of solid lipid nanoparticles of monobenzone was prepared to produce sustain release of monobenzone to produce whitening effect. Initially solid lipid nanoparticles were prepared by double emulsification solvent evaporation method by using lecithin. PVA and PEG-600 are used as emulsifiers. The prepared solid lipid nanoparticles were evaluated for particle size, shape, drug content, entrapment efficiency, zetapotential and in-vitro drug release. Of all the formulations developed formulation F9 have shown the desired results and is thus selected to prepare the gel. The gel loaded solid lipid nanoparticles were evaluated for pH and viscosity of the gel along with in-vitro drug release. It was found that gel loaded solid lipid nanoparticles were stable and the percentage of drug release was in a sustained manner for more than 24 hours. Keywords: Solid lipid nanoparticles, Monobenzone, Double emulsification solvent evaporation method, Lecithin. INTRODUCTION Colloidal particles ranging in size between 10 and 1000 nm are known as nanoparticles. They are manufactured from synthetic/natural polymers and ideally suited to optimize drug delivery and reduce toxicity [1]. Over the years, they have emerged as a variable substitute to liposomes as drug carriers. The successful implementation of nanoparticles for drug delivery depends on their ability to penetrate through several anatomical barriers, sustained release of their contents and their stability in the nanometer size to overcome these limitations of polymeric nanoparticles, lipids have been put forward as an alternative carrier, particularly for lipophilic pharmaceuticals. These lipid nanoparticles are known as solid lipid nanoparticles (SLNs), which are attracting wide attention of formulators world-wide [2]. SLNs are colloidal carriers developed in the last decade as an alternative system to the existing traditional carriers (emulsions, liposomes and polymeric nanoparticles). They are a new generation of submicron-sized lipid emulsions where the liquid lipid (oil) has been substituted by a solid lipid. SLN offer unique properties such as small size, large surface area, high drug loading and the interaction of phases at the interfaces, and are attractive for their potential to improve

performance of pharmaceuticals, neutraceuticals and other materials [3]. Solid lipid nanoparticles possess a solid lipid core matrix that can solubilize lipophilic molecules. They are made up of solid hydrophobic core having a monolayer of phospholipid coating. The lipid core is stabilized by surfactants (emulsifiers) and contains drug dispersed or dissolved in lipid matrix. They have potential to carry lipophilic or hydrophilic drugs [4]. Types of solid nanoparticles The types of SLNs depend on the chemical nature of the active ingredient and lipid, the solubility of actives in the melted lipid, nature and concentration of surfactants, type of production and the production temperature. Therefore 3 incorporation models have been proposed for study. SLN, Type I or homogenous matrix model The SLN Type I is derived from a solid solution of lipid and active ingredient. A solid solution can be obtained when SLN are produced by the cold homogenation method. A lipid blend can be produced

Corresponding Author:- B.Venkateswara Reddy Email:- [email protected]

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Vol 5 | Issue 3 | 2015 | 119-125. containing the active ingredient in a molecularly dispersed form. After solidification of this blend, it is ground in its solid state to avoid or minimize the enrichment of active molecules in different parts of the lipid nanoparticles. SLN, Type II or drug enriched shell model It is achieved when SLN are produced by the hot technique and the active ingredient concentration in the melted lipid is low during the cooling process of the hot o/w nanoemulsion the lipid will precipitate first, leading to a steadily increasing concentration of active molecules in the remaining melt, an outer shell will solidify containing both active ingredient and lipid. The enrichment of the outer area of the particles causes burst release. The percentage of active ingredient localized in the outer shell can be adjusted in a controlled shell model is the incorporation of coenzyme Q10. SLN, Type III or drug enriched core model Core model can take place when the active ingredient concentration in the lipid melt is high & relatively close to its saturation solubility. Cooling down of the hot oil droplets will in most cases reduce the solubility of the active ingredient in the melt. When the saturation solubility exceeds, active molecules precipitate leading to the formation of a drug enriched core [5]. Particulate systems like nanoparticles have been used as a physical approach to alter and improve the pharmacokinetic and pharmacodynamics properties of various types of drug molecules. Looking for drug carrier formulations increasing the bioavailability and consisting of well tolerated excipients, the solid lipid nanoparticles (SLN) are alterative drug carrier systems. Topical application of SLN gel offers a potential advantage of delivering the drug directly to the site of action, which will produce higher tissue concentrations [6]. Monobenzone is the monobenzyl ether of hydroquinone used medically for depigmentation. The topical application of monobenzone in animals increases the excretion of melanin from the melanocytes. The same action is thought to be responsible for the depigmenting effect of the drug in humans. Monobenzone may cause destruction of melanocytes and permanent depigmentation. The monobenzone topical application can produce uneven depigmentation effect, the problem is solved by uniform and sustain release of monobenzone form lipid matrix and there by maintain uniform whitening effect of skin. The gel formulation can have significant effect as cosmetic purpose [7, 8]. In the present investigation, solid lipid nanoparticles are prepared by using lecithine. MATERIALS AND METHODS Materials Monobenzone was obtained from Sigma aldrich, germany. Lecithine, Polyvinylalcohol and Poly ethylene glycol – 6000 were purchased from Yarrow chemicals pvt limited, Ahmadabad. Ethanol and Dimethyl sulphoxide

were purchased from Finar chemicals products, Mumbai. Methods Solubility of pure Monobenzone About 10 mg of pure monobenzone was dissolved in 10 ml of solvent like water, 0.1 N HCL, methanol, ethanol, Dichloro methane and phosphate buffer (pH 7.4). The solubility was observed by sedimentation of particles. Method of Preparation of Solid Lipid Nanoparticles Double Emulsification Solvent Evaporation Method [9]. Solid lipid nanoparticles of Monobenzone were prepared by w/o/w type double emulsification-solvent evaporation technique. Required quantity of drug (200mg of monobenzone) was dissolved in suitable organic solvent (Ethanol). Required quantity of lipid lecithin as mentioned in table-1 was dissolved in dichloromethane. The drug solution was added slowly to the lipid mixture and then homogenized for 15 mins in ultra probe sonicator. The resultant primary emulsion was poured into 1% PVA (or) 1% PEG-6000 solutions and homogenized for an additional 10 mins until formation of w/o/w emulsion. The solvent was removed by evaporating in a Rota vapor. The emulsion was freeze-dried at -20 ºC to get dried solid lipid nanoparticles. Evaluation of Solid Lipid Nanoparticles Morphology of Solid Lipid Nanoparticles Morphology of solid lipid nanoparticles was observed by Scanning Electron Microscope. A small amount of nanoparticle samples was spread on a metal stub. The stub was then coated with conductive gold by Hitachi 1010 ion sputter and was examined under Hitachi 3000N scanning electron microscope chamber. The image was photographed at an acceleration voltage of 20 kV with a chamber pressure of 0.6 mmHg [10]. Nanoparticles size Nanoparticles size was determined by using a Zetasizer 300 HS. Samples were diluted with distilled water and measurement was done at 25ºC. The diameter was calculated from the autocorrelation function of intensity of light scattered from nanoparticles. Zeta potential The charge of the nanoparticles was determined by measuring the zeta potential by laser dropper anemometry using Zetasizer 3000HS. Nanoparticles were diluted with distilled water and the samples were placed in the electrophoretic cell where the potential of 150 mV was established [11]. In-vitro release studies In-vitro drug release from SLN was determined by using Franz diffusion cell. The cell has 200 ml receptor volume. The area of diffusion was 5 cm². The cell was placed in between the cell stirrer and the water bath where

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Vol 5 | Issue 3 | 2015 | 119-125. the temperature was maintained at 32 ± 0.5°C. Cellophane membrane (molecular weight cut-off: 6000-8000) previously soaked in receptor medium was clamped in between the donor and the receptor chamber of diffusion cell. A suitable aliquot of the formulation (100mg of nanoparticles equivalent to 10 mg drug) was added to the donor chamber of the diffusion cell which was occluded with a paraffin film. The receptor medium (6.4 phosphate buffer) was stirred by magnetic bar. 5 ml sample was withdrawn from the receptor compartment at the following time intervals: 0.5,1, 2, 4, 6, 8, 12, 18 and 24 h and replaced by equal volume of the fresh receptor fluid. The samples withdrawn were centrifuged (20,000rpm, for 30 minutes, at cool temperature). Then drug content of supernatant was estimated by using U.V method [12].

Q = [Dε / τ (2 A - εCs) Cst] ½ Where, Q = Amount of drug released at time‘t’. D = Diffusion coefficient of the drug in the matrix. A = Total amount of drug in unit volume of matrix. Cs = the solubility of the drug in the matrix. ε = Porosity of the matrix. τ = Tortuosity. t = Time (hrs) at which ‘q’ amount of drug is released. Above equation may be simplified if one assumes that ‘D’, ‘Cs’, and ‘A’, are constant. Then equation becomes: Q = Kt1/2 When the data is plotted according to equation i.e. cumulative drug release versus square root of time yields a straight line, indicating that the drug was released by diffusion mechanism. The slope is equal to ‘K’.

Release kinetics The results of in-vitro release profile obtained for all the formulations were plotted in various kinetic models as follows, 1. Zero order kinetic model – Cumulative % drug released versus T. 2. First order kinetic model – Log cumulative percent drug remaining versus T. 3. Higuchi’s model – Cumulative percent drug released versus square root of T. 4. Korsmeyer equation / Peppa’s model – Log cumulative percent drug released versus log T [13].

Korsmeyer equation / Peppa’s model To study the mechanism of drug release from the the prepared solid lipid nanoparticles, the release data were also fitted to the well-known exponential equation (Korsmeyer equation / Peppa’s law equation), which is often used to describe the drug release behavior from polymeric systems. Mt / Mα = Ktn Where, Mt / Mα = the fraction of drug released at time‘t’. K = Constant incorporating the structural and geometrical characteristics of the drug / polymer system. N = Diffusion exponent related to the mechanism of the release. Above equation can be simplified by applying log on both sides, and we get: Log Mt / Mα = Log K + n Log t When the data is plotted as log of drug released versus log time, yields a straight line with a slope equal to ‘n’ and the ‘K’ can be obtained from y–intercept. For ‘n’ = 0.5 Fickian diffusion 0.5 < n > 1.0 Anomalous (non – Fickian) transport i.e. both diffusion and erosion. n = 1 or more indicates case-2 relaxation or super case -2 transport i.e. by erosion of polymeric chain.

Zero order kinetics Zero order release would be predicted by the following equation:At = A 0 – K 0 t Where, At = Drug release at Time‘t’. A0 = Initial drug concentration K0 = Zero – order rate constant (hr-1). When the data is plotted as cumulative percent drug release versus time, if the plot is linear then the data obeys Zero – order release kinetics, with a slope equal to K0. First Order Kinetics First – order release would be predicted by the following equation:Log C = log C0 – Kt / 2.303 Where, C = Amount of drug remained at time‘t’. C0 = Initial amount of drug. K = First order rate constant (hr-1). When the data is plotted as log cumulative percent drug remaining versus time yields a straight line, indicating that the release follow first order kinetics. The constant ‘K’ can be obtained by multiplying 2.303 with the slope values. Higuchi’s model Drug release from the matrix devices by diffusion has been described by following Higuchi’s classical diffusion equation.

Formulation and characterization of SLN loaded gel The polymer HPMC K100 was initially soaked in water for 12 hrs and dispersed by agitation at 600rpm by using magnetic stirrer to get smooth dispersion of gel. The previously prepared optimized solid lipid nanoparticles suspension was added to HPMC K100 gel [14]. The ingredients and the amount taken are mentioned in the table-2. PH and Viscosity of gel loaded SLN Solid lipid nanoparticles formulations containing monobenzone were characterized for pH using Digital pH meter. The viscosities of different solid lipid nanoparticle formulations were determined using cone and plate viscometer with spindle 61.

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Vol 5 | Issue 3 | 2015 | 119-125. In-vitro release studies The gel loaded solid lipid nanoparticle formulation equivalent to 10mg of monobenzone was placed in a glass tube. It was previously covered with soaked osmosis cellulose membrane, which acts as a donor compartment. The glass tube was placed in a beaker containing 100ml of phosphate buffer pH 6.4, which acts as receptor compartment. The whole assembly was fixed in such a way that the lower end of the tube containing suspension was just touched (1-2mm deep) the surface of diffusion medium. The temperature of receptor medium maintained at 37±20C and the medium was agitated at 600rpm speed using magnetic stirrer. Aliquots of 5ml sample were withdrawn periodically and after each withdrawal same volume of medium was replaced. The collected samples were analyzed at 270 nm in Double beam UV-VIS spectrophotometer using Phosphate buffer (pH 6.4) as blank. RESULTS AND DISCUSSION Preformulation Studies of Pure Drug Solubility study Solubility of monobenzone was performed in various solvents like water, 0.1 N HCL, methanol, ethanol, Dichloro methane and phosphate buffer (pH 7.4) and the results are represented in table-3. From the above solvents monobenzone was freely soluble in ethanol, whereas remaining solvents shows insoluble particle sediment in the bottom of test tube. The solubility study was found to be helpful in the development of analytical methods of drug and the selection of diffusion medium. Determination of melting point The melting point of Monobenzone was found to be 118ºC which complied with the BP standards. Evaluation of monobenzone solid lipid nanoparticles Morphology studies The morphology and surface character of monobenzone nanoparticles were observed by SEM and is shown in figure-1. The morphology of monobenzone nanoparticles prepared by Lecithin showed spherical shape with smooth surface. Particle size The particle size of prepared monbenzone solid lipid nanoparticles was analyzed by Malvern particle size analyzer. In the all the formulations size range was in between 296 nm to 516 nm and results are given in table-4. These sizes of nanoparticles were only used to improve the bioavailability of monobenzone drug. The lowest particle size contained formulation is F-9 (296 nm) and F-10 (316 nm). Drug Content The drug content of monobenzone solid lipid nanoparticles was determined by calculating the drug

present in centrifugation process and results are given in table-4. The drug content of F-1 to F-10 was in the range of 44 to 72%. The highest drug content contained formulations were F-9 (69.41%) and F-10 (72.70%). Drug entrapment efficiency The entrapment efficiency of monobenzone solid lipid nanoparticles was determined by calculating the unentrapped drug present in centrifugation process and results are given in table-4. The entrapment efficiency of F-1 to F-10 was in the range of 52.62 to 82.14%.The highest entrapment efficiency was observed in formulations F-9 (82.14%) and F-10 (78.12%). Zeta potential Zeta potential is a key factor to evaluate the stability of colloidal dispersion. In general, particle could be dispersed stabilized when value of zeta potential was in the range of -5 to + 20 mV which are due to electrical repulsion between particles. The average zeta potential obtained for formulations F-1 to F-10 nanoparticles was about -18 to -32 mV. It was concluded that the monobenzone solid lipid nanoparticles obtained in this study was a dynamic stable system. Results are given in table-4. In-vitro drug release solid lipid nanoparticle The in-vitro release of monobenzone from different biodegradable solid lipid nanoparticle was determined and the quantity of drug release in the formulations F-1 to F-10 of solid lipid nanoparticle was very low ie., in the range of 60-80% and is represented in table-5. From this, it is obvious that the decreased percentage of drug release was due to the more compact wall around the drug by the biodegradable polymer and it signifies that they possess a sustained drug release for a prolonged period of time in all the formulations. At the end of 24 h, limited percentage of drug was released. Finally the % CDR of best formulation is F-9 (61.5%) and F-10 (63.27%). In-vitro release kinetics The in-vitro release data was fitted into various kinetic equations i.e., zero order, first order, higuchi, korsemeyer. The release constant was calculated from the slope of appropriate plot and the regression [R2] was calculated and results are mentioned in the table-6. In the monobenzone solid lipid nanoparticles preparations of all formulations (F-1 to F-10), the invitro release kinetic was best fitted by zero order equation and the plots showed the high linearity [R2= 0.839 to 0.969] followed by first order [R2= 0.944 to 0.985] and higuchi equation [R 2= 0.972 to 0.991]. Hence the drug release kinetics demonstrated that the drug release was nearly independent of drug concentration. Korsemeyer- peppas equation has showed good linearity [R2= 0.890]. The release exponent n= 0.20.

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Vol 5 | Issue 3 | 2015 | 119-125. PH and Viscosity of gel loaded solid lipid nanoparticle formulation The gel was found to have smooth appearance and texture. The pH of gel was found to be in the normal pH range of skin 4.0 to 7.3. Hence the preparation was non-irritant in

nature. The viscosities of optimized formulation F 9 was found to be 5420 cP. The drug content value of given formulation was found to be 75.4% and in-vitro drug release was found to be 50.86% and the release profile is given in table-7.

Table 1. Composition of different formulations of Solid Lipid Nanoparticles Formulations Drug Lecithine PVA (%) PEG-6000 (%) (mg) (mg) (gm/ml) gm/ml F-1 200 200 1 _ F-2 200 300 1 _ F-3 200 400 1 _ F-4 200 500 1 _ F-5 200 200 _ 1 F-6 200 300 _ 1 F-7 200 400 _ 1 F-8 200 500 _ 1 F-9 200 300 1 _ F-10 200 400 _ 1

Ethanol (ml) 5 5 5 5 5 5 5 5 5 5

Table 2. Formulation of Solid Lipid Nanoparticles Loaded Gel Ingredients Formulated monobenzone SLN particles HPMCK100 Distilled water Table 3. solubility of drug in different solvents Solvent Water Ethanol Methanol 0.1 N Hcl 7.4 phosphate buffer

Water (ml) 5 5 5 5 5 5 5 5 5 5

DMSO (ml) _ _ _ _ _ _ _ _ 1 1

Quantity Q.S 150 ml 10 ml

Solubility (mg/ml) Insoluble 2mg/ml 0.2mg/ml 0.32mg/ml 1.12mg/ml

Table 4. Physical evaluation of monobenzone Solid Lipid Nanoparticles Formulation Particle size Drug content (%) code (nm) F1 394 51.23 F2 432 56.34 F3 480 44.45 F4 496 59.30 F5 408 44.01 F6 452 52.8 F7 490 57.52 F8 516 52.61 F9 296 69.41 F10 316 72.70

Entrapment efficiency (%) 54.24 63.10 65.10 69.72 52.62 59.2 64.16 71.04 82.14 78.12

Zeta potential (mV) - 32.26 - 29.3 - 25.4 - 23.1 - 34.92 - 30.72 - 28.12 - 25.4 - 19.02 - 18.24

Table 5. In-vitro release profile Solid Lipid Nanoparticle Time(hrs) 0.5 1 2 4

F1 12.72 20.41 23.69 31.13

F2 13.35 20.73 23.70 30.81

F3 16.22 23.61 29.77 37.23

Cumulative % drug release F4 F5 F6 F7 14.84 13.71 13.71 15.90 19.23 21.40 23.69 24.88 26.03 25.70 29.90 35.18 34.78 33.06 37.67 42.35

F8 18.29 26.00 34.51 40.01

F9 12.45 18.28 25.07 32.85

F10 14.48 18.74 25.31 32.29

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39.86 51.51 58.12 64.13

37.96 51.18 60.02 66.04

43.77 56.07 65.25 70.03

41.65 48.27 66.51 74.98

44.28 50.97 59.60 65.23

43.95 56.36 65.02 70.67

Table 6. Release kinetics data of the formulations F1 to F10 Formulation code Zero order R2 First order R2 F1 0.932 0.976 F2 0.952 0.971 F3 0.929 0.979 F4 0.969 0.985 F5 0.922 0.973 F6 0.916 0.974 F7 0.879 0.963 F8 0.937 0.983 F9 0.888 0.944 F10 0.909 0.957

52.73 61.26 69.20 74.62

51.64 61.04 68.19 80.72

Higuchi’s R2 0.991 0.986 0.989 0.986 0.991 0.983 0.972 0.990 0.976 0.982

Table 7. In-vitro release of gel loaded Solid Lipid Nanoparticle formulation S.No. Time (hr) 1 0.5 2 1 3 2 4 4 5 6 6 8 7 10 8 12 9 24

44.03 48.27 53.10 61.50

44.64 48.67 53.48 63.27

Korsemeyer’s n 0.403 0.406 0.365 0.380 0.388 0.386 0.408 0.361 0.425 0.378

% CDR 0.89 1.34 2.18 3.36 6.21 10.23 18.28 28.04 50.86

Fig 1. SEM studies solid lipid nanoparticles of F9 formulation

CONCLUSIONS Monobenzone is an oral and topical agent used as a skin whitening agent. The basic idea behind the development of such a system is to maintain a constant level of drug in the blood plasma. Monobenzone is suitable candidate for formulation into sustained dosage form in order to prolong the release of drug.The solid lipid nanoparticles were prepared by using various concentrations of lecithine and permeation enhancer (DMSO). The prepared SLN was evaluated for physicochemically parameters like particle size, entrapment

efficiency, drug content, zeta potential. The values were significantly suitable for stabilization of SLN and penetration capability via skin pores. The in-vitro drug release studies showed sustained action over prolong period of time. The optimized formulation (F-9) was loaded in HPMC K 100 gel and it was evaluated for viscosity, pH, drug content and drug release studies. From the above studies it was concluded that Monobenzone SLN loaded HPMC gel was suitable to provide whitening effect to skin for prolong period.

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Vol 5 | Issue 3 | 2015 | 119-125. REFERENCES 1. Manmode AS, Sarkarkar DM, Mahajan NM. Nanoparticles tremendous therapeutic potemtial: A review. Pharma tech res, 1(4), 2009, 1020-27. 2. Mukherjee S, Ray S, Thakur RS. Solid lipid nanoparticles: A modern formulation approach in drug delivery system. Indian Journal of Pharmaceutical Sciences, 71, 2009, 349-358. 3. Sinha Ranjan Vivek, Srivastava Saurabh, Goel Honey, Jindal Vinay. Solid Lipid Nanoparticles (SLN’S) – Trends and Implications in Drug Targeting. International Journal of Advances in Pharmaceutical Sciences, 1, 2010, 212-238. 4. Biswajit Basu. Solid lipid nanoparticles: A promising tool for drug delivery system. Journal of Pharmacy Research, 3, 2010, 84-92. 5. Rainer H. Muller, Karsten Mader, Sven Gohla. Solid lipid nanoparticles (SLN) for controlled drug delivery- A review of the state of the art. European journal of pharmaceutics and biopharmaceutics, 3(1), 2000, 161-177. 6. Jenning V, Gysler A, Schafer Korting M, Gohla S. Vitamin A loaded solid lipid nanoparticles for topical use: Occlusive properties and drug targeting to the upper skin. Eur J Pharm Biopharm, 49, 2000, 211-8. 7. Nath SK, Majumder PP, Nordlund JJ. Genetic epidemiology of vitiligo: Multilocus recessivity cross-validated. American Journal of Human Genetics, 55(5), 1994, 981–90. 8. Ole martin Rordm, Eric William Lenouvel and Martine Maalo. Successful treatment of extensive vitiligo with monobenzone. Journal of clinical and aesthetic and dermatology, 5(12), 2012, 36-39. 9. Rabinarayan Parhi, Padilama Suresh. Production of Solid Lipid Nanoparticles-Drug Loading and Release Mechanism. Journal of chemical and pharmaceutical research, 2(1), 2012, 211-22. 10. Ekambaram P and Hasan Sathali Abdul. Formulation and evaluation of solid lipid nanoparticles of ramipril. Journal of Young Pharmacist, 3(3), 2011, 216–220. 11. Anand Kumar Kushwaha, Parameswara Rao Vuddanda, Priyanka Karunanidhi, Sanjay Kumar Singh and Sanjay Singh. Development and Evaluation of Solid Lipid Nanoparticles of Raloxifene Hydrochloride for Enhanced Bioavailability. BioMed Research International, 584549, 2013, 1-9. 12. Madhushri M, Thakur R, Kiran K Jadhav, Ronak N. Formulation and evaluation of solid lipid nanoparticles containing clotrimazole. American journal of Pharma tech research, 2(3), 2012, 536-550. 13. Suvakanta Dash, Padala narasimha Murthy, Lilakantha Nath and Prasanta Chowdhury. Kinetic modeling on drug release from controlled drug delivery systems- A review. Acta Poloniae Pharmaceutica- Drug Research, 67(3), 2010, 217-23. 14. Jyotsana R. Madan, Priyanka A Khude, Kamal Dua. Development and evaluation of solid lipid nanoparticles of mometasone furoate for topical delivery. International journal of pharmaceutical investigation, 4(2), 2014, 60-64.

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