Development and evaluation of a controlled drug delivery wound dressing based on polymeric porous microspheres

Abstract

The aim of the present work was to develop and evaluate a controlled drug delivery wound dressing based on polymeric porous microspheres, which are also termed as microsponge drug delivery system. For this purpose, turmeric (drug)-based polymeric porous microspheres formulations were developed by quasi-emulsion solvent diffusion method. The production yields, actual drug content, drug entrapment efficiency, particle size, formulation of the material, and in vitro release were studied. On the basis of maximum drug released, a formulation was selected to incorporate into wound dressings with the help of a binder by spraying technique. Finally, the selected formulation and samples of wound dressings containing microsponges were subjected to scanning electron microscopy and drug release analyses. The result of in vitro release shows that microsponge drug delivery system is a versatile tool that has a potential to convert any wound dressing into a controlled drug delivery wound dressing.

Keywords

Controlled drug delivery wound dressing polymeric porous microspheres microsponges

Introduction

A wound dressing can use textile structure (woven, knitted, nonwoven, braided, composites) to cover and protect the wound from infection and microorganism [1]. A wound dressing plays an effective role to provide moist wound environment, protect the wound from the environmental microorganisms, and facilitate the wound healing process by introducing a drug [2]. Wound dressings can be classified into three groups based on their function (debridement, antibacterial, occlusive, absorbent, and adherence), material type (e.g., hydrocolloid, alginate, and collagen), and physical form (ointment, film, foam, gel). Broadly, they are classified as traditional dressings, moist wound management/modern dressings, medicated or drug delivery dressings, and controlled drug delivery (CDD) dressings [1,3]. A CDD dressing delivers the drug to wound sites in a consistent and sustained manner over a long period of time without involving any frequent change. Mostly it could be applied to a wound site in the form of polymers films or polymeric porous structures such as scaffolds [3].

A controlled release drug delivery system is a system that delivers the drug systematically at a predetermined rate for a specified period of time to its site of action [4]. There are many CDD systems used in pharmaceutics, medical, and health care sector that are incorporated into textile structure [5] such as cyclodextrins [6 –8], aza-crown ethers, fullerenes [9,10], fibers (electro spun biodegradable solid and core spun hollow fibers) [11 –20], and particulate (micro and nano) system [21 –23]. A polymeric porous microsphere (PPM) is a new and versatile controlled delivery tool that consists of porous microspheres [24 –26]. This system provides outstanding properties such as controlled drug release, site-specific action, and high drug load capacity along with thermal-, chemical-, and physical stability. They are also nontoxic, nonmutagenic, nonallergic, nonirritating, cost-effective in addition to the ease with which they can be developed [26 –28]. Its outstanding properties make it an effective tool to entrap a number of active agents for topical treatment (sunscreen, antiacne, anti-inflammatory, antifungal, antidandruff, antipruritics, skin depigmenting, and rubefacients agents) [29 –40], oral administration (fluribiprofen, paracitmol, etc) [41 –45], vascular wall reconstruction, cardiovascular engineering, biopharmaceuticals, bone substitution, and diagnoses of diseases [46 –49]. The microsponges release their active ingredients on a time mode and also in response to other stimuli such as rubbing, temperature, and pH etc [50 –52].

The aim of the present work was to develop a CDD dressing using polymeric porous particulate system or microsponge drug delivery system (MDS). For this purpose, the turmeric-based microsponge formulations were developed by quasi-emulsion solvent diffusion (ESD) method and incorporated into cotton (CN) (traditional) and calcium alginate (AN) moist management dressing by spraying technique. In microsponge formulations, turmeric was chosen as a drug that contains a variety of chemically rich compounds (curcumonoids). It also has many biological, pharmacological, and wound healing properties [53 –59]. To the best of our knowledge, PPM or MDS-based CDD dressing is being developed and evaluated for the first time.

Materials and methods

Materials

Eudragit RS 100 (copolymer of ethyl acrylate, methyl methacrylate, and trimethylammonioethyl methacrylate chloride) and turmeric were supplied by LAB ERA Scientific Store, Multan, Pakistan. Polyvinyl alcohol (PVA) 30,000–70,000, sodium hydroxide (NaOH), sodium chloride (NaCl), calcium chloride (CaCl₂), and dialysis tubing (40 kD) were from Sigma Aldrich. Ethanol, methanol, and monobasic potassium phosphate (KH₂PO₄) were from BDH laboratory, Riedel-deHean, and E. Merck, respectively. All chemicals used in this study were analytical grade. The nonwoven calcium alginate wound dressing (Kaltostat) from Convatec and traditional gauze dressing having the specifications plain weave, 15 tex warp, and weft linear density, 19 ends per inch, 15 picks per inch, and 20 gsm weight were purchased from the local medical store. Printofix LTC binder (low temperature curable [LTC]) was supplied by Archroma, Pakistan.

Method for preparation of microsponges

Microsponge formulations containing turmeric with different ratio of drug to polymer were prepared by quasi-ESD method. The drug to polymer ratio and different process variables used in ESD method are given in the Table 1. To prepare inner phase, Eudragit RS 100 and turmeric were dissolved in ethanol. The outer phase was prepared by dissolving PVA in distilled water at 60℃. Then, inner phase was poured into the outer phase under continuous stirring for specific time. Finally, the microsponges were washed, filtered, and dried in electrical oven at 50℃ for 24 h.

Table 1.

Production parameters of quasi-emulsion solvent diffusion method.

Specifications	Values
Turmeric: Eudragit RS 100	0.25:1, 0.50:1, 0.75:1, 1:1, 1.25:1, 1.50–1
Amount of ethanol in inner phase	5 ml
Amount of PVA in outer phase	50 mg
Amount of water for outer phase	100 ml
Temperature of inner phase	35 ℃
Stirrer type	Three bladed
Stirrer rate	1000 r/min
Stirrer time	120 min

Note: PVA: polyvinyl alcohol.

Characterization of microsponges

Determination of production yield

The production yield that is the ratio of weight of microsponges obtained to the initial weight of the raw materials (polymer + drug) expressed in percentage is calculated by using the following equation (1).

ProductionYield (%) = (Practicalmassofmicrosponges / Theoreticalmass) \times 100

(1)

Determination of actual drug content

The weighed samples of drug loaded microsponges (30 mg) were crushed and dissolved in methanol (10 ml). Each sample was then diluted into 10 times. All the samples were filtered and their absorbance values were measured at 424 nm using UV visible spectrometer (Perkin Elmer Model Lambda 25, USA). The actual drug content of these formulations was calculated from the standard calibration curve as shown in the Figure 1.

Figure 1.

Standard calibration curve for turmeric in methanol.

Determination of entrapment efficiency

Encapsulation efficiency was calculated from actual drug content by using equations (2) and (3).

TheoreticalDrugContent (%) = (Weightofdrugadded / Weightofpolymersanddrugadded) \times 100

(2)

EntrapmentEfficiency (%) = (ActualDrugContentinMicrosponges / TheoreticalDrugContent) \times 100

(3)

Particle size analysis

The particle size of the microsponges was measured by using Zeta sizer (ZEN 3600, Malvern Instruments, Worcestershire, UK).

Fourier Transform Infrared (FTIR) analysis

The FTIR Spectra of turmeric, Eudragit RS 100, and turmeric loaded microsponge formulation (FM-1 to FM-6) were measured in potassium bromide disks using a Perkin-Elmer Model 1600 FTIR spectrometer (USA).

In vitro drug release analysis from microsponges

The microsponges of 50 mg were put into 5 ml potassium phosphate buffer solution (PBS) having a pH 7.4, which is usually the condition for a chronic wound. The PBS containing drug-loaded microsponges was introduced in dialyzer tube (40 kD molecular weight cut off [MWCO] membrane). The dialyzer tube was then placed into a 45-ml cylinder also containing potassium phosphate buffer of 7.4 pH. Finally, cylinder containing release media (PBS) was stirred at a speed of 300 r/min by using a small magnetic stirrer bar under constant temperature (37℃).

The drug release in the outer solution as a result of diffusion from membrane was assessed by sampling the solution (PBS) at specific intervals of time. The drug content release from membrane as the results of diffusion was measured at 424 nm wave length by using UV visible spectrometer from the standard calibration curve as shown in the Figure 2.

Figure 2.

Standard calibration curve for turmeric in PBS.

In order to understand the release kinetics of drug, results of the in vitro drug release study were fitted with various kinetic models like zero order (cumulative percent drug released vs. time), first order (log cumulative percent drug retained vs. time), Higuchi (cumulative percent released vs. √time), and Hixson-Crowell’s cube root model ((percentage retained)^1/3 vs. time). The kinetic model that best fits the dissolution data was evaluated by comparing the regression coefficient values obtained in various models.

Incorporation of microspheres into textile dressings

The selection of a formulation to incorporate into wound dressings is based on highest cumulative drug release rate. The selected formulation was incorporated into calcium sodium alginate (AN) and cotton (CN) based wound dressings by spraying technique. The aqueous solution composed of a plurality of microsponges and an LTC binder was sprayed on samples. Finally, these samples were dried at room temperature and curing was carried out at 60℃ for 20 min in order to achieve the fixation of the microspheres.

Characterization of selected microsponge formulation and wound dressing containing microsponges

Surface morphology

The surface morphology of the selected microsponge formulation and wound dressings containing microsponges were studied by scanning electron microscopy (SEM) using a Quanta 250 FEI (USA).

In-vitro drug release analysis

Drug release from these dressings treated with microsponges was measured by placing a piece of 2.5 × 2.5 cm into 20 ml of 7.4 pH PBS solution under constant stirring at 35℃. The 2 ml sample from buffer solution was taken after specific intervals of time and replaced with the fresh buffer solution. The drug releases from dressing were measured at 424 nm wave length using UV visible spectrometer by using standard calibration curve as shown in the Figure 2.

Results and discussion

Characterization of microsponges

The production yield, actual drug content and entrapment efficiency, and mean particle size of turmeric-loaded microsponge formulations (FM1–FM6) are given in Table 2. The production yield, actual drug content, and entrapment efficiency of these formulations were increased by increasing the drug amount as compared to polymer. The FM-1 has low level of drug that causes rapid mixing of outer phase into inner phase and faster removal of solvent. It solidifies the polymer before the formation of droplet that decreases the production yield. On the other hand, FM-6 contains maximum level of drug. The maximum drug retards the diffusion of outer phase into inner phase and delays the polymer precipitation. As a result, more time is required for droplet formation that yields the highest production yield. More time for precipitation of polymer enables the microsponges to entrap more drug in its structure and increases the actual drug content and entrapment efficiency by increasing the amount of drug as compared to polymer [31,32,37,41,42,44,60,61].

Table 2.

Optimization of drug: polymer for preparation of turmeric-loaded microsponges.

Sample	Drug: polymer	Yield (% ± SD)	Actual drug content (% ± SD)	Entrapment efficiency (% ± SD)	Mean particle size (µm ± SD)
FM-1	0.25: 1	80.95 ± 2.04	16.65 ± 0.32	83.23 ± 0.72	190.47 ± 2.68
FM-2	0.50: 1	83.24 ± 3.13	28.30 ± 0.21	84.89 ± 0.64	172.68 ± 3.23
FM-3	0.75: 1	86.65 ± 2.78	36.73 ± 0.34	85.71 ± 0.80	155.37 ± 7.83
FM-4	1.00: 1	87.54 ± 2.35	44.02 ± 0.27	88.05 ± 0.54	134.40 ± 5.18
FM-5	1.25: 1	89.87 ± 2.87	50.49 ± 0.14	90.89 ± 0.25	118.29 ± 4.78
FM-6	1.50: 1	93.76 ± 2.45	54.51 ± 0.13	90.94 ± 0.21	82.65 ± 5.45

The particle size of turmeric-loaded microsponges was decreased by increasing the drug amount as compared to polymer. This decrease in particle size depends on the viscosity of organic phase. The viscosity of organic phase decreased due to decrease in polymer amount from FM-1 to FM-6. This decrease in viscosity results in small-sized emulsion droplets and consequently small-sized microsponges achieved [32,60,61].

The FTIR spectra of turmeric, Eudragit RS 100 and turmeric-loaded microsponge formulations (FM-1–6) are given in Figure 3. In FTIR spectra of turmeric, a hydroxyl stretching peak at 3303 cm⁻¹, a CH₃ band at 2950 cm⁻¹, a carbonyl stretching band at 1630 cm⁻¹, a C=C at 1540 cm⁻¹, were seen as reported in literature [61,62]. Eudragit RS 100 also showed a CH₃ band at 2950 cm⁻¹, an ester C=O stretching peak around 1734 cm⁻¹ and a C–O peak at 1150 cm⁻¹as reported [44].

Figure 3.

FTIR spectra of (a) turmeric (b) Eudragit RS 100, (c) FM-1, (d) FM-2, (e) FM-3, (f) FM-4, (g) FM-5, and (h) FM-6.

The turmeric-loaded microsponge formulations (FM-1–6) spectra shows all prominent peaks of polymer and drug at 3320 (phenolic OH), 2950 (alkane CH₃ stretching), 1720 (C=O ketone), 1540 (C=C), 1150 cm⁻¹ (C–O). It shows that drug was simply entrapped in the microspheres without any chemical reaction with the polymer.

In vitro drug release analysis

In vitro drug release study of microsponges was performed in phosphate buffer solution having a pH of 7.4. Figure 4 represents the release behavior of six microsponge formulations. The results show that the drug release from FM-1 is high within 24-h time period as compared to remaining formulations. It means that low drug to polymer ratio formulation, which has low drug content has released the drug quickly as compared to those formulations that have high drug content.

Figure 4.

In vitro drug release of turmeric from microsponge formulations.

Drug release data of all microsponge formulations were fitted into four mathematical models termed as zero order, first order, Higuchi model, and Hixson Crowell model to characterize the mechanism of drug release. The regression coefficients of all formulations are shown in Table 3. The results show that the drug releases from all the formulations follow Higuchi model [60].

Table 3.

Evaluation of release kinetics of turmeric-loaded microsponge formulations.

Model name	Regression coefficient
Model name	FM-1	FM-2	FM-3	FM-4	FM-5	FM-6
Zero order	0.89	0.94	0.93	0.87	0.94	0.85
First order	0.41	0.51	0.55	0.39	0.54	0.43
Higuchi	0.97	0.98	0.99	0.96	0.98	0.95
Hixson-Crowell’s	0.66	0.58	0.60	0.48	0.53	0.51

On the basis of highest cumulative drug release, FM-1 was selected to incorporate into calcium AN and CN-based wound dressings.

Characterization of selected microsponge formulation and wound dressing containing microsponges

Surface morphology study

The surface morphology of turmeric-loaded microsponge formulations (FM-1) prepared by ESD method and wound dressings containing microsponges were investigated by scanning electron microscope as shown in Figure 5(a) to (c). It was observed by SEM analysis that FM-1 formulation has uniform porous spheres [37,44,61] and has successfully incorporated into wound dressing.

Figure 5.

SEM images of (a) FM-1, (b) AN dressing, and (c) CN dressing.

In vitro drug release analysis from wound dressings containing microsponges

The in vitro release studies were performed in phosphate buffer solution having a pH 7.4. The cumulative drug releases from two samples are shown in Figure 6. The results show that the drug release from both samples was 85% up to 8-h time period. Drug release data from both samples fitted into four mathematical models named as zero order, first order, Higuchi model, and Hixson Crowell models. The regression coefficient of calcium alginate dressing is 0.99 and CN dressing is 0.98 showing that the drug releases from these samples follow zero order.

Figure 6.

In vitro drug release of turmeric from microsponge treated dressings.

Conclusion

In this study, turmeric-based micro porous spheres (microsponges) were developed, characterized, and incorporated into wound dressings. The micro porous particulates were developed by ESD method. The effect of drug to polymer ratio on yield, drug content, entrapment efficiency, particles size, and drug release was studied. It was found that drug content and entrapment efficiency were increased by increasing the drug amount as compared to polymer. Then, FM-1 formulation was incorporated into calcium alginate and cotton-based wound dressings by spraying technique. The surface morphology of the FM-1 formulation and wound dressing containing microsponges and drug release from these wound dressing were also studied. The results show that the drug release from both samples was more than 85% within 8 h. The study shows that microsponge drug delivery system (MDS) is a versatile tool. It has a potential to convert a traditional or a modern wound dressing into a CDD wound dressing. This system also has greater stability (physical, chemical, and thermal), ease in production, and much fever in cost as compared to cyclodextrins-based drug delivery system.

Footnotes

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

References

Gupta

Agarwal

Alam

. Textile-based smart wound dressings. Ind J Fibre Text Res 2010; 35: 174–187.

Rajendran

. Advanced textiles for wound care, New Delhi: Woodhead Publishing Limited, 2009.

Boateng

Mathews

Stevens

HNE

. Wound healing dressings and drug delivery systems: A review. J Pharm Sci 2008; 97: 2892–2923.

Chien

Lin

. Drug delivery: Controlled release. Encycl Pharm Technol 2007; 1: 1082–1103.

Nierstrasz

. Textile slow release systems with medical applications. Autex 2002; 2: 175–189.

Grigoriu

Popescu

. Applications of cyclodextrines in textiles—a review. Polit Iaşi 2011; 11: 47–65.

Voncina B. Application of cyclodextrins in textile dyeing. Textile Dyeing, www.intechopen.com, 2011, pp. 373–392 (accessed February 2014).

Vyas

Saraf

. Cyclodextrin based novel drug delivery systems. J Incl Phenom Macrocycl Chem 2008; 62: 23–42.

Bakry

Vallant

Haq

. Medicinal applications of fullerenes. Int J Nanomed 2007; 2: 639–649.

10.

Nagda

Rathore

Bharkatiya

. Bucky balls: A novel drug delivery system. J Chem Pharm Res 2010; 2: 240–248.

11.

Elahi

Guoping

. Core-shell fibers for biomedical applications—a review. Bioeng Biomed Sci 2013; 3: 1–14.

12.

Polacco

Cascone

Lazzeri

. Biodegradable hollow fibres containing drug-loaded nanoparticles as controlled release systems. Polym Int 2002; 51: 1464–1472.

13.

Zamani

Prabhakaran

Ramakrishna

. Advances in drug delivery via electrospun and electrosprayed nanomaterials. Int J Nanomed 2013; 8: 2997–3017.

14.

Cui

Zhu

. Investigation of drug release and matrix degradation of electrospun poly (DL-lactide) fibers with paracetanol inoculation. Biomacromolecules 2006; 7: 1623–1629.

15.

Cui

Zhou

Chang

. Electrospun nanofibrous materials for tissue engineering and drug delivery. Sci Technol Adv Mater 2010; 11: 1–11.

16.

Elakkiya

Malarvizhi

Rajiv

. Curcumin loaded electrospun Bombyx mori silk nanofibers for drug delivery. Polym Int 2014; 63: 100–105.

17.

Goldberg

Langer

Jia

. Nanostructured materials for applications in drug delivery and tissue engineering. J Biomater Sci Polym 2011; 18: 1–26.

18.

Huang

Z-M

Zhang

Y-Z

Kotaki

. A review on polymer nanofibers by electrospinning and their applications in nanocomposites. Compos. Sci. Technol 2003; 63: 2223–2253.

19.

Chen

. Micro and nano-fabrication of biodegradable polymers for drug delivery. Adv Drug Deliv Rev 2004; 56: 1621–1633.

20.

Pham

Sharma

Mikos

. Electrospinning of polymeric nanofibers for tissue engineering applications: A review. Tissue Eng 2006; 12: 1197–1211.

21.

Arora

Agarwal

Murthy

RSR

. Review article latest technology advances in cosmaceuticals. Int J Pharm Sci Drug Res 2012; 4: 168–182.

22.

Wang

Chen

. Aromachology and its application in the textile field. Fibres Text East Eur 2005; 13: 41–44.

23.

Singh

Varun

Behera

. Cosmetotextiles: State of art. Fibres Text East Eur 2011; 19: 27–33.

24.

Shafi

Duraivel

Bhowmik

. Micrrosponge drug delivery system. Ind J Res Pharm Biotechnol 2013; 1: 206–209.

25.

Ravali

Spandana

Shilpa

. A review on microsponges drug delivery system. Int J Pharm Res Rev 2013; 1: 309–335.

26.

Choudhari

Singh

. Microsponge—novel drug delivery system. Int J Med Pharm Sci Res Rev 2013; 1: 26–52.

27.

Gandhi

Jana

Sen

. Tailoring effect of microsponge for targeted drug delivery. J Sci Innov Res 2013; 2: 1073–1082.

28.

Jadhav

Patel

Mungekar

. Microsponge delivery system: An updated review, current status and future prospects. J Sci Innov Res 2013; 2: 1097–1110.

29.

Yadev

Nanda

. Development and evaluation of some microsponge loaded medicated topical formulations of Acyclovir. Int J Pharm Sci Res 2014; 5: 1395–1410.

30.

Ravi

. Standarization of process parameters involved erythormycin microsponges by Quassi emulsion solvent diffusion method. Int J Pharm Dev Technol 2013; 3: 28–34.

31.

Mayur

Ramesh

Nitin

. Ethyl cellulose based microsponges delivery system for anti-fungal vaginal gels of tioconazole. J Drug Deliv Ther 2013; 3: 14–20.

32.

Mohan

Veena

Manjula

. Formulation and evaluation of microsponges for topical drug delivery of mupirocin. Int J PharmTech Res 2013; 5: 1434–1440.

33.

Yasmeen

Chakravarthi

. Preperation and evaluation of microsponge loaded controlled release topical gel of Acylovir sodium. Int J Biopharm J 2012; 3: 96–102.

34.

Saboji

Manvi

Gadad

. Formulation and evaluation of ketoconazole microsponge gel by Quassi emulsion solvent diffusion. J Cell Tissue Res 2011; 11: 2691–2696.

35.

Ray

. Development and evaluation of xanthan gum-facilitated ethyl cellulose microsponges for controlled percutaneous delivery of diclofenac sodium. Acta Pharm 2011; 61: 257–270.

36.

Rekha

Manjula

. Formulation and evaluation of microsponges for topical delivery system of mometasone furoate. Int J Pharm Pharm Sci 2011; 3: 1–5.

37.

Amrutiya

Bajaj

Madan

. Development of microsponges for topical delivery of mupirocin. Am Assoc Pharm Sci 2009; 10: 402–409.

38.

John

. Topical anti-inflammatory gels of fluocinolone acetonide entrapped in eudragit based microsponge delivery system. Res J Pharm Tech 2008; 1: 502–506.

39.

Nokhodchi

Jelvehgari

Siahi

. Factors affecting the morphology of benzoyl peroxide microsponges. Micron 2007; 38: 834–840.

40.

Grimes

Pearl

. A microsponge formulation of the treatment of melasma and postinflammatory hyperpigmentation. Ther Clin 2004; 74: 362–368.

41.

Mishra

Shikhri

Sharma

. Optimization, formulation development and characterization of Eudragit RS 100 loaded microsponges and subsequent colonic delivery. Int J DRUG Discov Herb Res 2011; 1: 8–13.

42.

Jain

Singh

. Dicyclomine-loaded Eudragit®-based microsponge with potential for colonic delivery: Preparation and characterization. Trop J Pharm Res 2010; 9: 67–72.

43.

Deore

Mahajan

Deore

. Development and characterization of sustained release microspheres by quasi emulsion solvent diffusion method. Int J ChemTech Res 2009; 1: 634–642.

44.

Orlu

Cevher

Araman

. Design and evaluation of colon specific drug delivery system containing flurbiprofen microsponges. Int J Pharm 2006; 318: 103–117.

45.

Gade

Aparna

Keerthi

. Design and development of hydroxyzine hydrochloride controlled release tablets. Caribb J Sci Technol 2013; 1: 172–184.

46.

Patel

Oswal

. Nanosponge and micro sponges: A novel drug delivery system. Int J Res Pharm Chem 2012; 2: 237–244.

47.

Patil

Kemkar

Patil

. Microsponge drug delivery system: A novel dosage form. Am J PharmTech Res 2012; 2: 2249–3387.

48.

Saroj

. Microsponge as the versatile tool for drug delivery system. Int J Res Pharm Chem 2011; 1: 243–258.

49.

Kirti

Sushilkumar

. Solid porous microsphere: Emerging trend in pharmaceutical technology. Int J Pharma Bio Sci Rev 2011; 2: 364–377.

50.

Jain

Sharma

Banik

. Recent advances on microsponge delivery system. Int J Pharm Sci Rev Res 2011; 8: 13–23.

51.

Shaha

Jain

Krishna

. Microsponge drug delivery: A review. Int J Res Pharm 2010; 1: 212–218.

52.

Wasnik

Parmar

. The design of colon specific drug delivery system and different approches to treat colon disease. Int J Pharm Sci Rev Res 2011; 6: 167–177.

53.

Gul

Mujhahid

Jehan

. Studies on the antibacterial effect of different fractions of Curcuma Longa against urinary tract infection isolates. Pakistan J Biol Sci 2004; 7: 2055–2060.

54.

Han

Yang

. Antimicrobial activity of wool fabric treated with curcumin. Dye Pigment 2005; 64: 157–161.

55.

Joshi

Ali

Purwar

. Ecofriendly antimicrobial finishing of textiles using bioactive agents based on natural products. Indian J Fibre Text Res 2009; 34: 295–304.

56.

Kumar

Chomwal

Kumar

. Anti inflammatory and wound healing activity of Curcuma aromatica salisb extract and its formulation. J Chem Pharm Res 2009; 1: 304–310.

57.

Maheshwari

Singh

Gaddipati

. Multiple biological activities of curcumin: A short review. Life Sci 2006; 78: 2081–2087.

58.

Purohit

Solanki

Mathur

. Evaluation of wound healing activity of ethanolic extract of Curcuma longa rhizomes in male albino rats. Asian J Pharm Res 2013; 3: 79–81.

59.

Shimatsu

Kakeya

Imaizumi

. Clinical application of ‘curcumin’, a multi-functional substance. Anti-Aging Med 2012; 9: 43–51.

60.

Baykara

. Preparation and invitro evaluation of modified release ketoprofen microsponges. Farm 2003; 58: 101–106.

61.

Arya

Pathak

. Assessing the viability of microsponges as gastro retentive drug delivery system of curcumin: Optimization and pharmacokinetics. Int J Pharm 2014; 460: 1–12.

62.

Haiyee

Saim

Said

. Characterization of cyclodextrin complexes with turmeric oleoresin. Food Chem 2009; 114: 459–465.