“A STUDY TO IMPROVE THE SOLUBILITY OF POORLY SOLUBLE DRUGS BY USING SUITABLE PHARMACEUTICAL TECHNIQUES”

DISSERTATION PROTOCOL

SUBMITTED TO

RAJIV GANDHI UNIVERSITY OF HEALTH SCIENCES

BANGALORE, KARNATAKA.

BY

MOSALI SINDHU REDDY

M.PHARM, PART-I

DEPARTMENT OF PHARMACEUTICS

T.JOHN COLLEGE OF PHARMACY

GOTTIGERE, BANNERGATTA ROAD.

BANGALORE-83

UNDER THE GUIDANCE OF

Dr. SANDHYA K V,

DEPARTMENT OF PHARMACEUTICS,

T.JOHN COLLEGE OF PHARMACY,

GOTTIGERE, BANNERGATTA ROAD,

BANGALORE-83.

RAJIV GANDHI UNIVERSITY OF HEALTH SCIENCES,

BANGALORE, KARNATAKA.

ANNEXURER-II

PROFORMA FOR REGISTRATION OF SUBJECTS FOR DISSERTATION

1. / NAME OF THE CANDIDATE
AND ADDRESS (IN BLOCK LETTERS) / MOSALI SINDHU REDDY
T.JOHN COLLEGE OF PHARMACY, GOTTIGERE, BANNERGHATTA ROAD,
BANGALORE-83,
KARNATAKA.
2. / NAME OF THE INSTITUTION / T.JOHN COLLEGE OF PHARMACY, GOTTIGERE,BANNERGHATTA ROAD,
BANGALORE-83,
KARNATAKA.
3. / COURSE OF STUDY AND SUBJECT / MASTER OF PHARMACY IN PHARMACEUTICS
4. / DATE OF ADMISSION OF COURSE / 06-07-2011
5. / TITLE OF TOPIC / “A STUDY TO IMPROVE THE SOLUBILITY OF POORLY SOLUBLE DRUGS BY USING SUITABLE PHARMACEUTICAL TECHNIQUES”
6. / SIGNATURE OF THE CADIDATE / (Mosali Sindhu Reddy)
7. / REMARKS OF THE GUIDE / RECOMMENDED FOR THE DISSERTATION WORK
8. / NAME AND DESIGNATION (in block letters)
8.1 GUIDE
8.2 SIGNATURE / SANDHYA KV, M. Pharm, Ph.D.
DEPARTMENT OF PHARMACEUTICS
T.JOHN COLLEGE OF PHARMACY.
(Sandhya KV, M. Pharm, Ph.D.)
8.3 HEAD OF THE DEPARTMENT
8.4 SIGNATURE / SANDHYA KV, M. Pharm, Ph.D.
DEPARTMENT OF PHARMACEUTICS
T.JOHN COLLEGE OF PHARMACY.
(Sandhya KV M, Pharm, Ph.D.)
9. / 9.1 REMARKS OF PRINCIPAL
9.2 SIGNATURE / FORWARDED AND RECOMMENDED FOR FAVOURABLE CONSIDERATION.
( Dr.Vineeth Chandy)
10.
11
12 / BRIEF RESUME OF THE INTENDED WORK:
10.1 NEED FOR THE STUDY:
Oral ingestion is the most convenient and commonly employed route of drug delivery due to its ease of administration, high patient compliance, cost-effectiveness, least sterility constraints and flexibility in the design of dosage form.The preferred oral route of administration is limited to those drug molecules that are permeable across the gastric mucosa and are at least sparingly soluble.An increasing number of newly developed drug candidates present poor water-solubility, which is the rate-limiting step to absorption of drugs from the gastrointestinal tract. Approaches to overcome this factor are of great importance in drug formulation Together with membrane permeability, the solubility/dissolution behavior of a drug is a key determinant to its oral bioavailability. At present about 40% of the drugs being in the development pipelines are poorly soluble, even up to 60% of compounds coming directly from synthesis are poorly soluble.
The solubility of a solute is the maximum quantity of solute that can dissolve in certain quantity of solvent or quantity of solution at a specified temperature.
Definition / Parts of solvent required for one part of solute
Very soluble / < 1
Freely soluble / 1 – 10
Soluble / 10 – 30
Sparingly soluble / 30 – 100
Slightly soluble / 100 – 1000
Very slightly soluble / 1000 - 10,000
Insoluble / > 10,000
Various formulation techniques are applied to compensate for their insolubility, slow dissolution rate and consequently poor therapeutic efficacy. These include formulation of the amorphous solid form, nanoparticles, microemulsions, solid dispersions; melt extrusion, salt formation and formation of water soluble complexes.
The Biopharmaceutics Classification System (BCS) is a scientific framework for classifying a drug substance based on its aqueous solubility and intestinal permeability. The BCS takes into account three major factors namely solubility, intestinal permeability, and dissolution rate, all of which govern the rate and extent of oral drug absorption. It classifies drugs into four classes. Class II consists of water-insoluble drugs which, when dissolved, are well absorbed from the gastrointestinal tract.
In this present study we would be working on drugs belonging to class II of BCS classification. The dissolution rate is usually the rate-limiting step in drug absorption. Commonly drugs in this class have variable absorptions due to the numerous formulation effects and in vivo variables that can affect the dissolution profile. Thus the need to improve the solubility of drugs by using various formulation strategies like nanoparticles, microemulsions, solid dispersions; melt extrusion, salt formation and formation of water soluble complexes to enhance their bioavailability, without changing the intrinsic ability of the drug molecules to permeate biomembranes.[1]
10.2 REVIEW OF LITERATURE :
Extensive literature review was made by referring various National and International Journals, various databases and other web resources along with general books for pharmaceutical scientists.
DANDAGI PM et al (2011), worked on nanocrystallization in enhancing dissolution property of poorly soluble drugs such as griseofulvin by emulsion solvent diffusion method using acetone and ethanol as solvents for drug. The formulations made of acetone were of smaller size and possessed better dissolution velocity compared to ethanol, thus concluding that formulating poorly water soluble drugs in the form of nanocrystallization would be a promising approach in delivery of class II drugs by oral route in much efficacious way to enhance their bioavailability[1].
MUKHERJEE S et al (2012), reviewed on solubility enhancement techniques for the improvement of effective absorption and bioavailability [2].
SHUKLA M et al (2010), workedon the effect of solubility of glipizide by using different solubilization techniques such as solid dispersion, hydrotropy and micellar solubilization. The drug glipizide showed improvement in solubility which was found to decrease in order of hydrotropic solubilization > solid dispersion technique > micellar solubilization, concluding that the best solubility results were obtained from hydrotropic solubilization method[3].
VARSHNEY S et al (2012), reviewed on employing different methods for solubility enhancement of norflaxacin including solid dispersions, complexation (in presence of acidic solubilizing additives; by EDTA and sodium caprate; and metal ion interaction), hydrotropic solubilization, crystal modification resulting in improved dissolution and bioavailability of drug leading to better therapeutic profile of drug[4].
BANSAL K et al (2011), worked onmicronization technique for improving the dissolution of Norethindrone where particle size reduction was achieved by air jet milling resulting in micronized Norethindrone showing higher dissolution rate. This suggests that micronization technique can be used for the preparation of rapidly dissolving formulations of Norethindrone, and could potentially lead to improvement in the in-vivo bioavailability of oral Norethindrone Tablets[5].
GRACE FX et al (2012), worked on comparing the solubilising efficiency of five different surfactants represented by Sodium Lauryl Sulphate, Tween 80,Polyethylene Glycol 6000, Cremophor RH40, Poloxamer 407 on class II (low solubility, high permeability) antidiabetic drugs such as Pioglitazone Hydrochloride and Glimepiride used in the treatment of type II Diabetes mellitus (NIDDM) resulting that among the five surfactants used, Poloxamer 407 showed better dissolution and resulted in a stable dosage form[6].
HARTI JE, et al (2012), worked on to increase the apparent water solubility of josamycin, an antibiotic belonging to the family of macrolide, by inclusion complexation with γ- cyclodextrin (γ-CD). The phase-solubility profile and the stability constant of the complex showed an improvement of the aqueous solubility of Josamycin propionate[7].
NAYAK AK et al (2012), worked oncomparing the cosolvency using three different cosolvents, namely PEG 400, PG, and glycerin on the aqueous solubility enhancement of a poorly aqueous soluble drug etoricoxib. The less-polar solvents were found to increase the aqueous solubility by greater extent, thus accentuating hydrophobic interaction mechanism and among the various solvent-cosolvent blends investigated, water-PEG 400 was an acceptable cosolvent in terms of side-effect profile and most efficient solubilizing cosolvent useful in the development of liquid dosage forms containing etoricoxib[8].
HUH KM et al (2005), worked on hydrotropic polymer micelles, consisting of a hydrophilic PEG shell and a hydrophobic core that contains a significant amount of hydrotropic moieties for solubilization of poorly soluble drugs such as paclitaxel where the hydrotropic polymer micelles exhibited a high drug loading capacity with enhanced long-term stability presenting an alternative and promising approach in formulation of poorly soluble drugs [9].
MUDIT D et al (2011), worked on preparation of freeze dried crystals of poorly soluble drug, indomethacin by freeze drying technique using solvent composition of isopropyl alcohol (10ml): water mixtures in ratio of 50:50. This resulted in decreased crystallinity and improved micromeritic properties which lead to improved dissolution and solubility compared to the commercial sample. Thus this method was useful in the formulation of indomethacin tablets by direct compression method[10].
RAI VK et al (2010), studied the role of various hydrophilic binders for enhancement of dissolution of a poorly soluble drug, raloxifene hydrochloride (RLX-HCl), using solid oral dosage form. Hydrophilic binders such as polyvinyl pyrrolidone, hydroxy propyl methyl Cellulose, hydroxy propyl cellulose were investigated. The formulation using hydrophobic binder ethyl cellulose showed significant improvement in dissolution behavior of drug [11].
PATEL ND et al (2011), reviewed on lipid based formulations with particular emphasis on self emulsifying drug delivery system (SEDDS), to improve the oral bioavailability of lipophilic drugs. It was observed that in SEDDS, the lipid matrix interacts readily with water, forming a fine particulate oil-in-water (o/w) emulsion and the emulsion droplets delivered the drug to the gastrointestinal mucosa in the dissolved state, readily accessible for absorption with increase in AUC.[12].
MAHESHWARI RK et al (2010), worked on a poorly water-soluble drug, frusemide.The drug was solubilized using hydrotropic blend containing 5 M urea, 1 M sodium acetate and 0.4 M sodium citrate for the spectrophotometric analysis precluding the use of organic solvents concluding that the proposed method is new, simple, accurate, cost-effective, safe, economic, precise and can be successfully employed in the routine analysis of frusemide in bulk and tablets[13].
PATEL A et al (2011), prepared solid dispersion of furosemide to increase the solubility by using different concentration of polyethylene glycol 4000. Formulation containing Furosemide/PEG 4000 (1:5) showed 92.4% increase in dissolution after 30 minutes in 0.1 N HCl compared with pure drug resulting as a promising approach for enhancing solubility and dissolution rate due to an increase in wetting properties and surface of drug available for dissolution[14].
KINI AG et al (2011), prepared microspheres of Piroxicam to improve the solubility and dissolution using two gradeS of chitosan with different drug polymer ratio by spray‐drying technique. This resulted in decreased crystallinity and improved the solubility and dissolution compared with pure piroxicam. Thus this method could be used for formulation of tablets of piroxicam by direct compression with directly compressible tablet excipients[15].
10.3OBJECTIVES OF THE STUDY:
  • The present study is planned with the following objectives:
Preformulation studies of the drugs and polymers and drug-polymer interaction studies by IR, DSC (Differential scanning calorimetry), X-ray diffraction, etc.
Develop suitable method(s) of estimation of the drug(s).
Enhancing the solubility and permeability of the selected drugs using the following methods:
a) Chemical modification by salt formation.
b) Physical modification by micronisation technique.
c) Alteration of solvent composition by using co-solvents, and surfactants.
d)Carrier systems such as cyclodextrins, micelles, and liposomes.
Evaluation of the solubility and permeability profile of the drug
Formulation into suitable dosage form(s) and evaluation
The best formulations in each category would be subjected to stability tests as per ICH guidelines.
MATERIALS AND METHODS:
Materials:
a)Surfactants (Polyoxyethylene stearate , Deoxycholic acid, Tweens and Spans , Sodium lauryl sulphate , Tween 80, PEG 6000 , Poloxamer 407 , Cremophor RH40).
b) Co-solvents(propylene glycol, ethanol, glycerine, and polyethylene glycol).
c)Polymers (Polyvinylpyrrolidone, PEG-4000, PEG-6000, Carboxymethyl cellulose, Hydroxypropyl cellulose, Guar gum, Xanthan gum, Sodium alginate, Methyl cellulose, HPMC, Dextrin, Cyclodextrins, Galactomannan).
d) Cyclo dextrins(methyl, hydroxypropyl,sulfoalkylated and sulfated derivatives of natural cyclodextrins).
Drug:
Class II drugs in BCS classification (Mebendazole, Griseofulvin etc)
Method:
1)Micronization:
Micronization is reduction of particle size up to micron level. In order to get better dissolution, there is a need to increase solubility and micronization.It is used as one of the solubilising tool to increase solubility. By micronization we get uniform and narrow particle size distribution which is essential for developing uniform dosage form.The following methods which can be used for achieving micronization are jet milling , solid solution & eutectic mixtures, microprecipitation & microcrystalization, controlled crystallization, supercritical fluid technology, spray freezing into liquid and spray freeze dry (SFD).
2)Use of co-solvents:
Co-solvent formulations of poorly soluble drugs can be prepared orally and parenterally. The most frequently used low toxicity cosolvents for parenteral use are propylene glycol, ethanol, glycerine, and polyethylene glycol. Dimethylsulfoxide(DMSO) and dimethylacetoamide (DMA) have been widely used as cosolvents because of their large solubilization capacity for poorly soluble drugs and their relatively low toxicity.Co-solvents may be combined with other solubilization techniques and pH adjustment to further increasesolubility of poorly soluble compounds.
11.1. Source of Data
1) Review of literature from:
a. Journals: such as
-Indian Journal of Pharmaceutical Science
-International Journal of Pharmaceutical.
-Biomaterials.
-Pharmaceutical Research.
-European Journal of Pharmaceutical Sciences.
-Drug Development and Industrial Pharmacy.
b. Internet browsing.
c. Helinet,rguhs.ac.in
2) e-Library: T.John college of pharmacy.
.
11.2. Method of Collection Of Data
•Laboratory studies which include, preformulation studies, formulation and evaluation studies such as amount of drug released rate kinetics &stability studies etc.
•Data of physiochemical properties of the drug and polymers used such as solubility in various solvents, pH will be collected through literature search.
11.3. Does the study require any investigation or intervention to be conducted on patients or other humans or animals? If so, please mention briefly.
-NO-
11.4. Has ethical clearance been obtained from your institution in case of 11.3?
- NOT APPLICABLE-
LIST OF REFERENCES:
1.Phanchaxari M, Kaushik S, Telsang S,Enhancement of Solubility and Dissolution property of Griseofulvin by Nanocrystallization, Int J. Drug Dev. & Res., 3(2) P 180-191 (2011) .
2.Mukherjee S, Patel P, Patel A, Patel H, Patel P,A Review on Solubility Enhancement Techniques, International Journal Of Pharmaceutical Research And Bioscience, volume1 (1)(2012).
3. Shukla M, Rathore P, Jain A, Nayak S ,Enhanced Solubility study of Glipizide using different Solubilization techniques,Int J Pharm Pharm Sci ,vol 2, issue2, (2010).
4.Varshney S, Tiwari A, Negi D, Khulbe P, Singhal P,Solubility Enhancement of Norfloxacin: a Review, Journal of Sciences, 02(01),(2012).
5.Bansal K, Pant P, Rao P, Padhee K, Sathapathy A and Kochhar P ,Micronization and Dissolution Enhancement of Norethindrone, International Journal Of Research In Pharmacy And Chemistry, , 1(3), (2011).
6. Grace X, Latha S, Shanthi S, Reddy C,Comparative study of Different Surfactants for Solubility Enhancement of Two class ii drugs for Type ii Diabetes mellitus, ,Int J Pharm Pharm Sci , 2(4), (2012).
7.Harti J, Cherrah Y, and Bouklouze A,Improvement of Water Solubility of Josamycin by Inclusion complex with γ-Cyclodextrin, International Scholarly Research Network,Isrn Analytical Chemistry,Volume (2012).
8.Nayak A and Panigrahi P, Solubility Enhancement of Etoricoxib by Cosolvency approach , International Scholarly Research Network, Isrn Physical Chemistry,Volume (2012).
9. Huh K, Lee S, Cho Y, Lee J, Jeong J, Park K, Hydrotropic Polymer Micelle system for Delivery of Paclitaxel, J Control Release ,101 P 59–68 (2005).
10. Mudit D, Keshavarao K, Vamsi Krishna N, Lavanya D, Anil G, Enhancing Solubility and Dissolution of Indomethacin by Freeze Drying, International Research Journal Of Pharmacy,(2011).
11.Rai V. k., Rajput BS, Sharma M, Agarwal A, GuptaA and Singh N, Solubility Enhancement of Poorly water-soluble drug (Raloxifene hydrochloride) by using Different Hydrophilic binders in Solid dosage form, Pharmacie Globale International Journal Of Comprehensive Pharmacy,(2010).
12. Patel ND , Patel KV, Panchal LA, Shukla AK, Shelat PK.,An Emerging technique for Poorly Soluble Drugs: Self Emulsifying Drug Delivery System,International Journal Of Pharmaceutical & Biological Archives, 2(2) P 621-629, (2011).
13. Maheshwari RK, Juneja C and Juneja N, Application of Mixed-Hydrotropic Solubilization concept in Spectrophotometric analysis of Frusemide in Tablet dosage form” , The Pharma Research (T. Ph. Res.), 3 P 243-248 (2010).
14.Patel A, Prajapati P, Boghra R, Shah D, Solubility Enhancement of Poorly Aqueous Soluble Furosemide using PEG-4000 by Solid Dispersion,Asian J Pharm Clin Res (ajpscr) issue 2, vol. 1 P 1-9. (2011).
15.Kini A, Dixit M and Kulkarni PK, Enhancement of Solubility and Dissolution rate of Poorly Water Soluble drug by Spray Drying using different grade of Chitosan” , Int J Pharm Pharm Sci, vol 3,2 ,(2011).

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