The document discusses dissolution modeling and its importance in predicting drug release kinetics. It describes 10 common dissolution models including diffusion layer, Danckwert's, interfacial barrier, zero-order, first-order, Higuchi, Korsmeyer-Peppas, Hixson-Crowell, Baker-Lonsdale, and Weibull models. Each model has a unique equation to characterize drug release based on factors like solubility, surface area, diffusion coefficients and particle size. Understanding these models helps optimize formulations and develop in vitro-in vivo correlations to reduce bioequivalence studies.
UNIT V
Mucoadhesive Delivery Systems:
Mechanism of bioadhesion, mucoadhesive materials, formulation and evaluation of Buccal and Nasal drug delivery systems.
UNIT V
Mucoadhesive Delivery Systems:
Mechanism of bioadhesion, mucoadhesive materials, formulation and evaluation of Buccal and Nasal drug delivery systems.
Modeling and comparison of dissolution profiles - Review by Paulo Costa*, Jos...MAHENDRA PRATAP SWAIN
Over recent years, drug release / dissolution from solid pharmaceutical dosage forms has been the subject of intense and profitable scientific developments. Whenever a new solid dosage form is developed or produced, it is necessary to ensure that drug dissolution occurs in an appropriate manner. The pharmaceutical industry and the registration authorities do focus, nowadays, on drug dissolution studies. The quantitative analysis of the values obtained in dissolution / release tests is easier when mathematical formulas that express the dissolution results as a function of some of the dosage forms characteristics are used. In some cases, these mathematics models are derived from the theoretical analysis of the occurring process. In most of the cases the theoretical concept does not exist and some empirical equations have proved to be more appropriate. Drug dissolution from solid dosage forms has been described by kinetic models in which the dissolved amount of drug is a function of the test time. Some analytical definitions of function are commonly used, such as zero order, first order, Hixson–Crowell,Weibull, Higuchi, Baker–Lonsdale, Korsmeyer–Peppas and Hopfenberg models. Other release parameters, such as dissolution time, assay time, dissolution efficacy, difference factor (f1), similarity factor (f2) and Rescigno index can be used to characterize drug dissolution / release profiles.
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
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!
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
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
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.
Anti ulcer drugs and their Advance pharmacology ||
Anti-ulcer drugs are medications used to prevent and treat ulcers in the stomach and upper part of the small intestine (duodenal ulcers). These ulcers are often caused by an imbalance between stomach acid and the mucosal lining, which protects the stomach lining.
||Scope: Overview of various classes of anti-ulcer drugs, their mechanisms of action, indications, side effects, and clinical considerations.
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
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
HOT NEW PRODUCT! BIG SALES FAST SHIPPING NOW FROM CHINA!! EU KU DB BK substit...GL Anaacs
Contact us if you are interested:
Email / Skype : kefaya1771@gmail.com
Threema: PXHY5PDH
New BATCH Ku !!! MUCH IN DEMAND FAST SALE EVERY BATCH HAPPY GOOD EFFECT BIG BATCH !
Contact me on Threema or skype to start big business!!
Hot-sale products:
NEW HOT EUTYLONE WHITE CRYSTAL!!
5cl-adba precursor (semi finished )
5cl-adba raw materials
ADBB precursor (semi finished )
ADBB raw materials
APVP powder
5fadb/4f-adb
Jwh018 / Jwh210
Eutylone crystal
Protonitazene (hydrochloride) CAS: 119276-01-6
Flubrotizolam CAS: 57801-95-3
Metonitazene CAS: 14680-51-4
Payment terms: Western Union,MoneyGram,Bitcoin or USDT.
Deliver Time: Usually 7-15days
Shipping method: FedEx, TNT, DHL,UPS etc.Our deliveries are 100% safe, fast, reliable and discreet.
Samples will be sent for your evaluation!If you are interested in, please contact me, let's talk details.
We specializes in exporting high quality Research chemical, medical intermediate, Pharmaceutical chemicals and so on. Products are exported to USA, Canada, France, Korea, Japan,Russia, Southeast Asia and other countries.
HOT NEW PRODUCT! BIG SALES FAST SHIPPING NOW FROM CHINA!! EU KU DB BK substit...
disso models ppt
1.
2. 2
Objectives:
Dissolution science is not just a quality control tool.
Apart from that in present era dissolution data act as
surrogate marker for in-vivo bioavailability .
Along with wide versatility of application to
pharmaceutical scientist it also form basis for setting
specification to allow the release of batch to market.
Present seminar try’s to give a bird eye view of
various dissolution model’s which will be helpful in
predicting the drug release kinetics ( dissolution
kinetics.)
3. DISSOLUTION
Dissolution is a process in which a solid substance
solubilizes in a given solvent i.e. mass transfer from
the solid surface to the liquid phase
Rate of dissolution is the amount of drug substance
that goes in solution per unit time under standardized
conditions of liquid/solid interface, temperature and
solvent composition
3
4. Why dissolution studies?
1. To show that the release of drug from the
tablet is close to 100%.
2. To show that the rate of drug release is
uniform batch to batch.
3. And to show that release is equivalent to
those batches proven to be bioavailable
and clinically effective.
4
5. Factors affecting Drug Dissolution
Factors relating to the physicochemical
properties of drug.
i. Solubility
ii. Particle size and
effective surface area
of the drug
iii. Polymorphism and
amorphism
iv. Salt form of the drug-
Factors relating to the dosage forms.
i. Pharmaceutical excipients –
Diluents
Lubricants
Binders
Surfactants
Colorants
Disintegranting Agents
ii. Method of granulation –
Wet granulation
Direct compression
Agglomerative phase of
communication (APOC)
5
6. DISSOLUTION MODEL’s & IT’s NEED
Dissolution Profile- It is graphical representation [in
terms of concentration vs. time] of complete release of
A.P.I. from a dosage form in an appropriate selected
dissolution medium.
i.e. in short it is the measure of the release of A.P.I
from a dosage form with respect to time.
IT’s NEED
To Develop invitro-invivo correlation which can
help to reduced costs, speed-up product
development and reduced the need of perform costly
bioavailability human volunteer studies.
To stabilize final dissolution specification for
the pharmacological dosage form
6
7. TYPES OF DISSOLUTION MODELS
1 • Diffusion layer model
2 • Danckwert’s MODEL
3 • Interfacial barrier model
4 • Zero-order model
5 • First-order model
6 • Higuchi model
7 • Korsmeyer-Peppas model
8 • Hixson-Crowell model
9 • Baker-Lonsdale model
10 • Weibull model 7
8. 1. DIFFUSION LAYER MODEL
Formation of a thin film at the interface, called as stagnant
layer.
2 steps are involved:
i. Interaction of solvent with drug surface to form a saturated
drug layer , called stagnant layer.
ii. Diffusion of drug molecules from stagnant layer into bulk of
the system.
9. 1. DIFFUSION LAYER MODEL (contd…)
Using Fick’s law, Noyes-Whitney equation for DIFFUSION LAYER
MODEL is as follows
Where,
dC/dt = dissolution rate of the drug.
D = diffusion coefficient of the drug.
A = surface area of the dissolving solid
Kw/o = water/oil partition coefficient of drug
V = volume of dissolution medium
h = thickness of stagnant layer
Cs–Cb = concentration gradient of diffusion of drug
9
10. 2. DANCKWERT’s MODEL
The Danckwert’s model is expressed by following equation:
Where,
• m=mass of solid dissolved
• ү = rate of surface renewal.
Danckwert’s model assumes that turbulence in the dissolution
medium exists at solid –liquid interface.
The agitated fluid consists of macroscopic masses of
eddies(packets of solvent molecules)which keep continuously
moving in arandom fashion and touch the surface of solid
particle.
The solid-liquid contact (interface) results in diffusion of drug
into packets wherein drug loaded packets move into the bulk of
solution.
10
11. 2. DANCKWERT’s MODEL (contd…)
In agitated fluid drug loaded packets are continuously replaced by
fresh packets due to which drug conc at solid liquid interface
never reaches saturation concentration.
Since the solvent packets continuously replace the surface of the
solid , it is called as SATURATION RENEWAL THEORY
11
12. 3. INTERFACIAL BARRIER MODEL
Interfacial barrier model considers drug dissolution as crystal
dissolution wherein solids get hydrated initially and is not
instantaneous
The reaction at solid surface and its diffusion across the interface
is slower than diffusion across liquid film
Therefore the rate of solubility of solid in liquid film becomes the
rate limiting than the diffusion of dissolved molecules
When considering the dissolution of the crystal will have a different
interfacial barrier given by following equation,
G = ki (Cs – Cb)
Where,
G = dissolution per unit area
Ki = effective interfacial transport constant
12
13. 4. Zero-order model
Drug dissolution from dosage forms that do not disaggregate and
release the drug slowly can be represented by the equation:
Q0-Qt = K0t
Rearrangement of equation yields:
Qt = Q0 + K0t
where ,
Qt is the amount of drug dissolved in time t,
Q0 is the initial amount of drug in the solution (most times, Q0 =
0) and K0 is the zero order release constant expressed in units of
concentration/time.
The release rate
is independent
of concentration
13
14. 5. First-order model
This model is used to describe absorption and/or elimination of
some drugs. The release of the drug which followed first order
kinetics can be expressed by the equation:
LOG CUM.%DRUG
REMAINING
dC/dt = -Kc
TIME
The plot between Time (hrs) vs log cumulative % of drug remaining
to be release gives straight line.
14
15. 6. HIGUCHI MODEL
Higuchi developed models to study the release of water
soluble and low soluble drugs incorporated in semisolid
and solid matrices.
To study the dissolution from a planar system having a
homogeneous matrix the relation obtained was;
A = [D (2C – Cs)Cs × t]1/2
Where,
A is the amount of drug released in time ‘t’ per unit
area,
D is the diffusivity of drug molecules in the matrix
substance
C is the initial drug concentration,
Cs is the drug solubility in the matrix media
15
16. 6. HIGUCHI MODEL (contd…)
Applications:
Higuchi describes the drug release as a diffusion process based
on Ficks law, square root time dependent .
This model is useful for studying the release of water soluble and
poorly soluble drugs from variety of matrices ,including solids
and semi solids.
16
17. 7. Hixson-Crowell model
Hixon-Crowell recognized that the particle regular area is
proportional to the cubic root of its volume, and hence desired
an equation as
1/3- M1/3 = K × t
Mo
where, Mo = original mass of particles
K = cube-root dissolution rate constant
M = mass of the A.P.I at the time ‘t’
APPLICATIONS:
To evaluate the drug release with changes in the surface area
and the diameter of the particles /tablets
The rate of dissolution depends on the surface of solvent - the
larger is area the faster is dissolution.
It describes the drug releases by dissolution, with the changes
in surface area and diameter of the particles or tablets.
17
18. 7. Hixson-Crowell model (contd…)
The plotted graph will be linear if the following conditions
are fulfilled:-
The equilibrium conditions are not reached and
The geometrical shape of the pharmaceutical dosage form
diminishes proportionally over time.
18
19. 8. Korsmeyer-Peppas model
The KORSEMEYAR AND PEPPAS empirical expression relates the
function of time for diffusion controlled mechanism.
It is given by the equation :
Mt / Ma = Ktn
where,
Mt / Ma is fraction of drug released
t = time
K=constant includes structural and geometrical characteristics
of the dosage form
n= release component which is indicative of drug release
mechanism
where , n is diffusion exponent.
i. If n= 1 , the release is zero order .
ii. n = 0.5 the release is best described by the Fickian diffusion
iii. 0.5 < n < 1 then release is through Anomalous diffusion
19
20. 10.Korsmeyer-Peppas model (contd…)
Application:
This equation has been used to the linearization of release data
from several formulations of microcapsules or microspheres
Use to analyze the release of p’ceutical polymeric dosage form.
When the release mechanism is not known or when more than
one type of release phenomena could be involved.
20
21. 9.Baker-Lonsdale model
This model was developed by Baker and Lonsdale (1974) from the
Higuchi model and described the drug release from spherical
matrices according to the equation
F= 3/2 [1-(1-At/A∞)2/3]-At/A∞
= (3DmCms) / (r02C0) X t
Where,
At is the amount of drug released at time’t’
A∞ is the amount of drug released at an infinite time,
Dm is the diffusion coefficient,
Cms is the drug solubility in the matrix,
ro is the radius of the spherical matrix
Co is the initial concentration of the drug in the matrix
21
22. 10. Weibull model
Weibull model is generally applied to drug dissolution or
release from pharmaceutical dosage forms. The accumulated
fraction of the drug M in solution at time t is given by Weibull
equation:
M = M0[1-e-(t-T/a)b]
Where,
m = % dissolved at time ‘t’
a = scale parameter which defines time scale of the
dissolution process
T1 = location parameters which represents lag period
before the actual onset of dissolution process (in most of
the cases T1 = 0)
b = shape parameter which quantitatively defines the curve
Application:
The Weibull model is more useful for comparing the release
profiles of matrix type drug delivery
22
23. 1) Remington's “The science and practice of pharmacy” 21st
edition page no 672-685.
2) “A Text book of Applied Bio pharmaceutics and
pharmacokinetics”, by Leon Shargel,andrew , 4 th edition
,page no 131-195.
3) “Text book of Bio pharmaceutics and pharmacokinetics”
,by V.Venkateshwarlu page no.32-55.
4) “Text book of Bio pharmaceutics and pharmacokinetics”,
by Brahmankar.page no.15-48.
5) European Journal of Pharmaceutical sciences 13 (2001)
page no.123 – 133.
6) Mathematical models of dissolution- Master’s thesis by
Jakub ˘ Cupera May 4, 2009 Masarykova Univerzita
7) Vinod P. Shah The role of dissolution testing in the
regulation of pharmaceuticals: The FDA perspective,
Taylor and Francis Group 2005 page no.81-95.
23
References
24. CONCLUSION
The Quantitative interpretation of the values
obtained n dissolution assays is easier using
mathematical equations which describe the release
profile in function of some parameters related with
the pharmaceutical dosage forms.
The release models with the major appliance and
the best describing drug release phenomena.
The Higuchi model has a larger application in
polymeric systems, the zero order model becomes
ideal to describe coated dosage forms or membrane
controlled dosage forms.
24