This document discusses various techniques for enhancing the solubility of drugs, including particle size reduction, hydrotropy, cosolvency, solubilization by surfactants, solid dispersions, pH adjustment, high pressure homogenization, supercritical fluid recrystallization, sonocrystallization, complexation, spray drying, inclusion complex formation, liquisolid technique, microemulsions, and self-emulsifying drug delivery systems. Particle size reduction techniques like micronization and nanosuspensions increase surface area to enhance dissolution rate and solubility. Other techniques utilize excipients like surfactants, cosolvents, and polymers to solubilize drugs.
Introduction
Effect of bonding on solubility
Importance of Solubility
Types of Solutions
Factor affecting Solubility
Phase Solubility Analysis
Need for solubility enhancement
Technique for solubility enhancement
Reference
Dissolution, factors affecting drug dissolution, methods to evaluate dissolution, advantages and disadvantages, recent approaches--these are the topics covered in this presentation.
The presentation provides a concise information regarding various methods or techniques for enhancing solubility of different drugs and will prove useful to students & researchers.
SOLID DISPERSION
Definition: The technology is the science of dispersing one or more active ingredients in an inert matrix in the solid stage.
Need of solid dispersion:
Increases Oral bioavailability of a drug
Increased dissolution rate.
Enhanced release of drugs from ointment.
Improved the solubility & stability.
The concept of solid dispersion was originally proposed by Sekiguchi & obi.
Increasing the dissolution, absorption & therapeutic efficacy of drugs in dosage forms.
Increasing solubility in water.
Improving the oral absorption and bioavailability of BCS Class II drugs.
A co solvent system is one in which a water miscible or partially miscible organic solvent is mixed with water to form a modified aqueous solution. And the phenomenon called Cosolvency
cosolvents have some degree of hydrogen bond donating and or hydrogen bond accepting ability as well as small hydrocarbon regions.
The resulting solution will have physical properties that are intermediate to that of the pure organic solvent and water through the reduction of water–water interaction.
Introduction
Effect of bonding on solubility
Importance of Solubility
Types of Solutions
Factor affecting Solubility
Phase Solubility Analysis
Need for solubility enhancement
Technique for solubility enhancement
Reference
Dissolution, factors affecting drug dissolution, methods to evaluate dissolution, advantages and disadvantages, recent approaches--these are the topics covered in this presentation.
The presentation provides a concise information regarding various methods or techniques for enhancing solubility of different drugs and will prove useful to students & researchers.
SOLID DISPERSION
Definition: The technology is the science of dispersing one or more active ingredients in an inert matrix in the solid stage.
Need of solid dispersion:
Increases Oral bioavailability of a drug
Increased dissolution rate.
Enhanced release of drugs from ointment.
Improved the solubility & stability.
The concept of solid dispersion was originally proposed by Sekiguchi & obi.
Increasing the dissolution, absorption & therapeutic efficacy of drugs in dosage forms.
Increasing solubility in water.
Improving the oral absorption and bioavailability of BCS Class II drugs.
A co solvent system is one in which a water miscible or partially miscible organic solvent is mixed with water to form a modified aqueous solution. And the phenomenon called Cosolvency
cosolvents have some degree of hydrogen bond donating and or hydrogen bond accepting ability as well as small hydrocarbon regions.
The resulting solution will have physical properties that are intermediate to that of the pure organic solvent and water through the reduction of water–water interaction.
Definition of solubility,
What is solubility Enhancement,
techniques which are used to enhance or increase solubility
Methods used to enhance/increase the solubility, physical modification (Particle size Reduction, Nanosuspension, micronization, Polymorphs), chemical modification(change of pH, use of buffer, complexation, salt formation), other modification (Sonocrystalization, Supercritical fluid process, microemulsion, solubilizers, hydrotrophy
solubility enhancement and cosolvency by madhavishaikhazaroddin
“cosolvency and soluility enhancement” Pharmatech 2003, 160-166. They had developed simultaneous determination of sitagliptin phospate monohydrate and metformin by ultra performance liquid chromatographic (uplc)method.
Knee anatomy and clinical tests 2024.pdfvimalpl1234
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The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Ve...kevinkariuki227
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
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Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
Explore natural remedies for syphilis treatment in Singapore. Discover alternative therapies, herbal remedies, and lifestyle changes that may complement conventional treatments. Learn about holistic approaches to managing syphilis symptoms and supporting overall health.
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
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Solubility enhancement by using various techniques
1. PRESENTED BY- PRAJAKTA CHAVAN
M.PHARM II nd SEMESTER
MODERN COLLEGE OF PHARMACY(FOR
LADIES),MOSHI ,PUNE
1
SOLUBILITY ENHANCEMENT BY
VARIOUS TECHNIQUES
2. CONTENTS-
2
INTRODUCTION
IMPORTANCE OF SOLUBILITY
NEED OF IMPROVING SOLUBILITY
TECHNIQUES OF SOLUBILITY
ENHANCEMENT
APPLICATIONS
3. INTRODUCTION
3
Solubility :
The term ‘Solubility’ is defined as maximum amount of
solute that can be dissolved in a given amount of solvent to
form a homogenous system at specified temperature.
The solubility of a drug is represented through various
concentration expressions such as parts, percentage,
molarity, molality, volume fraction, mole fraction.
4. Table 1: USP & BP Solubility criteria
4
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
6. NEED FOR SOLUBILITY ENHANCEMENT
6
There are variety of new drugs & their derivatives are available. But
less than 40% of lipophilic drugs candidates fail to reach market due
to poor bioavailability, even though these drugs might exhibit
potential pharmaco-dynamic activities.
The lipophilic drug that reaches market requires a high dose to attain
proper pharmacological action.
The basic aim of the further formulation & development is to make
that drug available at proper site of action within optimum dose.
7. Solubility of drug is largely due to,
1 Polarity of the solvents, that is, to its dipole moment. A polar solvent dissolves
ionic solutes and other polar substances.
2 The ability of solute to form hydrogen bond with solvent.
3 Also depends on the ratio of the polar to non polar groups of the molecule.
As the length of a non-polar chain of an aliphatic alcohol increases, the
solubility of the compound in water decreases.
Straight chain monohydric alcohols, aldehyde, ketones, and acids with more
than four or five carbons cannot enter into the hydrogen bonded structure of water
and hence are only slightly soluble.
7
8. Process of solubilisation
8
1) The separation of the molecule of the solvent to
provide space in the solvent for solute.
2) The breaking of intermolecular ionic bonds in
the solute.
3) The interaction between the solvent and the
solute molecule or ion.
9. When additional polar groups are present in the molecule, as
found in tartaric acid, propylene glycol, glycerin, water solubility
increases greatly.
Branching of the carbon chain reduces the non-polar effect and
leads to increased water solubility.
Tertiary butyl alcohol is miscible in all proportions with water,
where as n-butyl alcohol is slightly dissolved.
9
12. PARTICLE SIZE REDUCTION
The solubility of drug is often intrinsically related to drug particle size as a
particle becomes smaller, the surface area increases,increase in solubility.
TECHNIQUES OF PARTICLE SIZE REDUCTION-
1. Micronization
2. Nanosuspension
Micronization:
Micronization increases the dissolution rate of drugs through increased surface
area; by decreasing particle size, it does not increase equilibrium solubility.
Micronization of drugs is done by milling techniques using jet mill, rotor stator
colloid mills and so forth .
Micronization is not suitable for drugs having a high dose number because it
does not change the saturation solubility of the drug
12
13. 2) Nanosuspension:
This technology is applied to poorly soluble drugs that are insoluble in
both water and oils.
A pharmaceutical nanosuspension is biphasic systems consisting of nano sized drug
particles stabilized by surfactants for either oral and topical use or parenteral and
pulmonary administration.
The particle size distribution of the solid particles in nanosuspensions is usually less
than one micron with an average particle size ranging between 200 and 600 nm.
3)HYDROTROPY:
Hydrotropy is a solubilization phenomenon whereby addition of large
amount of a second solute results in an increase in the aqueous solubility of existing
solute.
Concentrated aqueous hydrotropic solutions of sodium benzoate, sodium salicylate,
urea, nicotinamide, sodium citrate, and sodium acetate have been observed to enhance
the aqueous solubilities of many poorly water-soluble drugs.
13
14. 4)COSOLVENCY:-
The solubility of poorly soluble drugs in water can be increased by mixing
it with some water miscible solvent in which the drug is readily soluble. This
process is known as cosolvency and the solvent used in combination are known
as cosolvent.
Cosolvent system works by reducing the interfacial tension between the
aqueous solution and hydrophobic solute & it is known as solvent blending.
The cosolvents are having hydrogen acceptor or donor groups with a small
hydrocarbon region. The hydrophobic hydrocarbon region usually interferes with
the hydrogen bonding network of water which consequently reduces the
intermolecular attraction of water while the hydrophilic hydrogen bonds ensures
water solubility.
14
15. 5)SOLUBILIZATION BY SURFACTANTS:-
Surfactants are the agents which reduces surface tension and enhance the
dissolution of lipophilic drugs in aqueous medium.
The surfactants are also used to stabilize drug suspensions.
When the concentration of surfactants more than their critical micelle
concentration (CMC, which is in the range of 0.05–0.10% for most
surfactants), micelle formation occurs which entrap the drugs within the
micelles. This is known as micellization and generally results in enhanced
solubility of poorly soluble drugs.
15
16. 6)SOLID DISPERSION:
Solid dispersion as group of solid products consisting of at least two
different components, generally, a hydrophilic matrix, and a hydrophobic drug.
Solid dispersion can also be referred as the dispersion of one or more active
ingredients in an inert matrix at solid state prepared by the melting,
solvent, and melting solvent method.
Hydrophilic carriers used for solid dispersions include polyvinyl pyrrolidone,
polyethylene glycols, Plasdone-S630.
Many times surfactants may also used in the formation of solid dispersion.
Surfactants like Tween- 80, Docusate sodium, Myrj-52, Pluronic-F68 and
Sodium Lauryl Sulphate are used
16
17. TECHNIQUES OF SOLID DISPERSION
The fusion (melt) method:
Accurately weighed amounts of carrier(s) are placed in an aluminum pan on a
hot plate and liquefy, with constant stirring, at a temperature of about 60°C.
An accurately weighed amount of active drug is incorporated into the melted carrier(s) with stirring to
ensure homogeneity. The mixture is heated until a clear homogeneous melt is obtained.
The pan is then removed from the hot plate and allowed to cool at room temp.
The solvent method:
Accurately weighed amounts of active drug and carrier(s) are dissolved in minimum quantities of
chloroform in a round-bottom flask. The solvent is removed using a rotary evaporator.
The obtained solid dispersion is transferred on to the aluminum pan and
allowed to dry at room temperature.
17
18. 7)Dropping method:
A solid dispersion of a melted drug-carrier mixture is pi petted and then
dropped onto a plate, where it solidifies into round particles.
The size and shape of the particles can be influenced by factors such as the
viscosity of the melt and the size of the pipette. Because viscosity is highly
temperature dependent, it is very important to adjust the temperature so that
when the melt is dropped onto the plate it solidifies to a spherical shape.
8)pH ADJUSTMENT:-
To access the solubility of this approach, the buffer capacity and tolerability
of the selected pH are important to consider.
Solubilized excipients that increase environmental pH within the dosage
form to a range higher than pKa of weekly acidic drugs increase the solubility
of that drug, those excipients that act as alkalizing agents may increase the
solubility of weekly basic drugs.
18
19. 9)High-pressure homogenization:-
It has been used to prepare nanosuspension of many poorly water soluble
drugs. In this method, the suspension of a drug and surfactant is forced under
pressure through a nanosized aperture valve of a high pressure homogenizer.
The principle of this method is based on cavitation in the aqueous phase. The
cavitations forces within the particles are sufficiently high to convert
the drug microparticles into nanoparticles.
The concern with this method is the need for small sample particles before
loading and the fact that many cycles of homogenization are required.
10)SUPERCRITICAL FLUID RECRYSTALLIZATION(SCF):-
19
20. Those fluids are referred to as supercritical fluids which are having temperature and
pressure greater than its critical temperature and critical pressure so as they are acquire
properties of both gas and liquid.e.g-carbon dioxide.
As the drug gets solubilized within SCF they can be recrystallized with reduced particle
size of drug.
11)SONOCRYSTALLISATION:-
The novel approach for particle size reduction on the basis of crystallization by
using ultrasound is Sonocrystallisation.
Sonocrystallisation utilizes ultrasound power characterized by a frequency
range of 20–100 kHz for inducing crystallization.
It’s not only enhances the nucleation rate but also an effective means of size
reduction and controlling size distribution of the active pharmaceutical
ingredients.
Most applications use ultrasound in the range 20 kHz-5 MHz
20
21. 12)COMPLEXATION:-
Complexation of drugs with cyclodextrins has been used to enhance
aqueous solubility and drug stability.
Cyclodextrins of pharmaceutical relevance contain 6, 7 or 8 dextrose
molecules (α, β, γ-cyclodextrin) bound in a 1,4-configuration to form rings of
various diameters.
The ring has a hydrophilic exterior and lipophilic core in which
appropriately sized organic molecules can form noncovalent inclusion
complexes resulting in increased aqueous solubility and chemical stability.
Complexation relies on relatively weak forces such as London forces,
hydrogen bonding and hydrophobic interactions.
TECHNIQUE OF COMPLEXATION
1. Physical Mixture:
Active drug with suitable polymer in different ratios mixed in a mortar for
about one hour with constant trituration. The mixture is passed through sieve
no. 80 21 and stored in dessicator over fused calcium chloride.
22. Kneading Method:
Active drug with suitable polymer in different ratios is added to the mortar and
triturated with small quantity of ethanol to prepare a slurry
Slowly the drug is incorporated into the slurry with constant trituration.,The
prepared slurry is then air dried at 250C for 24hrs.
The resultant product is pulverized and passed through sieve no. 80 and stored
in dessicator over fused calcium chloride
Co-precipitate
Method:
Active drug is dissolved in ethanol at room temperature and
suitable polymer is dissolved in distilled water.
Different molar ratios of active drug and suitable polymers are mixed
respectively.
The mixture is stirred at room temperature for one hour and the
solvent is evaporated. The resultant mass is pulverized
and passed through 22 sieve no. 80 and stored in a desiccators.
23. SPRAY DRYING:
The solvent evaporation of drug and polymer solution in different
ratio is carried out by using spray dryer.
The solutions are prepared by dissolving drug in methanol and polymer
in distilled water and mix both solutions, which produces a clear
solution.
The solvent evaporated by using evaporator.
The spray dried mixture of drug with polymer is obtained in 20–30 min.
23
24. 14)INCLUSION COMPLEX FORMATION-BASED
TECHNIQUES
24
Inclusion complexes are formed by the insertion of the
nonpolar molecule or the nonpolar region of one molecule
(known as guest)into the cavity of another molecule or
group of molecules (known as host).EXA- cyclodextrin
The cavity of host must be large enough to accommodate
the guest and small enough to eliminate water, so that the
total contact betweenthe water and the nonpolar regions of
the host and the guest is reduced
25. TECHNIQUES OF INCLUSION COMPLEX METHOD-Lyophilization/
Freeze-Drying Technique:
In order to get a porous, amorphous powder with high degree of interaction
between drug and CD.
In this technique, the solvent system from the solution is eliminated
through a primary freezing and subsequent drying of the solution containing both
drug and CD at reduced pressure.
Thermolabile substances can be successfully made into complex form by this
method.
limitations –
1. Use of specialized equipment,
2. Time consuming process,
3. Poor flowing powdered product.
Microwave Irradiation Method:
This technique involves the microwave irradiation reaction between drug and
complexing agent using a microwave oven.
25
26. LIQUISOLID TECHNIQUE:-
where a liquid may be transformed into a free flowing, readily
compressible and apparently dry powder by simple physical
blending with selected carrier and coating material.
The liquid portion, which can be a liquid drug, a drug suspension
or a drug solution in suitable non-volatile liquid vehicles, is
incorporated into the porous carrier material.
Once the carrier is saturated with liquid, a liquid layer is formed
on the particle surface which is instantly adsorbed by the fine
coating particles.
Thus, an apparently dry, free flowing, and compressible powder
is obtained.
26
27. MICRO-EMULSION:-
A micro emulsion is an optically clear pre-concentrate, isotropic, thermo
dynamically stable transparent (or translucent) system, containing a mixture of
oil, hydrophilic surfactant and hydrophilic solvent which dissolves a poorly
water soluble drug.
Micro-emulsions have been employed to increase the solubility of many
drugs that are practically insoluble in water, along with incorporation of
proteins for oral, parenteral, as well as percutaneous /transdermal use.
SELF-EMULSIFYING DRUG DELIVERY SYSTEMS:
It use the concept of in situ formation of emulsion in the gastrointestinal
tract.
The mixture of oil, surfactant, co-surfactant, one or more hydrophilic
solvents and cosolvent forms a transparent isotropic solution that is known as
the self-emulsifying drug delivery system (SEDDS).
The poorly soluble drug can be dissolved in a mixture of surfactant and oil
27which is widely known as preconcentrate.
28. Self-emulsifying drug delivery systems (SEDDS) and selfmicroemulsifying
drug delivery systems (SMEDDS) are isotropic solutions of oil and surfactant
which form oil-in-water microemulsions on mild agitation in the presence of water.
NEUTRALLIZATION-Drug
is added in alkaline solution like sodium hydroxide, ammonium
hydroxide.
A solution of β- Cyclodextrin is then added to dissolve the joined
drug. The clear solution obtained after few seconds under agitation is
neutralized using HCl solution until reaching the equivalence point.
At this moment, the appearance of a white precipitate could be
appreciated, corresponding to the formation of the inclusion compound.
The precipitate is then filtered and dried
28
29. CRYOGENIC METHOD:
It is developed to enhance the dissolution rate of drugs by creating
nanostructured amorphous drug particles with high degree of porosity at very
low-temperature conditions.
Cryogenic inventions can be defined by the type of injection device (capillary,
rotary, pneumatic, and ultrasonic nozzle), location of nozzle (above or under the
liquid level), and the composition of cryogenic liquid (hydrofluoroalkanes, N2,
Ar, O2, and organic solvents).
POLYMERIC ALTERATION:
Different crystalline forms of a drug that may have different properties are
known as Polymorphs.
Polymorphs may differ in physicochemical properties such as physical and
chemical stability, shelf-life, melting point, vapor pressure, intrinsic solubility,
dissolution rate, morphology, density and biological activities as well as
bioavailability.
metastable crystalline polymorphs, metastable forms are associated with
higher energy with increased surface area, subsequently solubility,
29bioavailability and efficacy.
30. SALT FORMATION:
Dissolution rate of particular salt is usually different from that of
parent compound.
Sodium and potassium salt of week acid dissolve more rapidly than that of
pure salt.
Limitation of salt formation-
epigastric distress due to high alkalinity,
reactivity with atmospheric water and carbon dioxide leads to precipitation,
patientcompliance and commercilation
30
31. APPLICATION OF SOLUBILITY
31
Solubility is represents a fundamental concept in fields of
research such as chemistry , physics, food science,
pharmaceutical, and biological sciences.
The solubility of a substance becomes specially important in the
pharmaceutical field because it often represents a major factor
that controls the bioavailability of a drug substance
Solubility is commonly used to describe the substance, to
indicate a substance's polarity ,to help to distinguish it from other
substances, and as a guide to applications of the substance.
32. Solubility of a substance is useful when separating mixtures.
Moreover, solubility and solubility-related properties can also provide
important information regarding the structure of drug substances, and in their
range of possible intermolecular interactions.
32