Brief description of targeted drug delivery system, along with its concept and strategies for drug targeting. Advantages and disadvantages of drug targeting
Need for drug targeting.
‘Targeted drug delivery system is a special form of drug delivery system where the medicament is selectively targeted or delivered only to its site of action or absorption and not to the non-target organs or tissues or cells.’
Brief description of targeted drug delivery system, along with its concept and strategies for drug targeting. Advantages and disadvantages of drug targeting
Need for drug targeting.
‘Targeted drug delivery system is a special form of drug delivery system where the medicament is selectively targeted or delivered only to its site of action or absorption and not to the non-target organs or tissues or cells.’
Nucleic acid based therapeutic drug delivery systemtadisriteja9
Nucleic acid based Drug delivery system is one of the trending research area, which i have taken and made as Powerpoint for easy and quick learning purpose
Nucleic acid based therapeutic drug delivery systemtadisriteja9
Nucleic acid based Drug delivery system is one of the trending research area, which i have taken and made as Powerpoint for easy and quick learning purpose
Buccal drug delivery system is part of mucoadhesive drug delivery system and their principal and formulation ,mechanisam of adhesion to mucosa ,use of polymers in BDDS and permiability enhancers and evaluation parameters of buccal tablets and patchs
Avoid first pass effect,
Brain Targeted Drug Delivery System
Prepared by :
Surbhi
M.Pharmacy II sem
Submitted to :
Dr. Anupama Diwan
MAGIC BULLET : CONCEPT OF PAUL EHRLICH
Brain Targeting: Challenges
Blood brain barrier (BBB): Brain is tightly segregated from the circulating blood by a unique membranous barrier.
The brain and spinal cord are lined with a layer of special endothelial cells that lack fenestrations and are sealed with tight junctions that greatly restrict passage of substances from the bloodstream.
These endothelial cells, together with perivascular elements such as astrocytes and pericytes, constitute the BBB.
Rate-limiting factor in determining permeation.
The factors affecting particular substance to cross BBB
Drug related factors at the BBB
Concentration at the BBB and the size,
Flexibility,
Conformation,
Ionization (nonionized form penetrates BBB)
Lipophilicity of the drug molecule,
Cellular enzyme stability and cellular sequestration,
Affinity for efflux mechanisms (i.e. P-glycoprotein),
Hydrogen bonding potential (i.e. charge),
Affinity for carrier mechanisms, and
Effect on all of the above by the existing pathological conditions
Transport Mechanisms
Several specialized transport mechanisms of solute transfer across endothelial cells and into the brain interstitium are also present within the BBB Carrier system for monosaccharides, monocarboxylic acid, neutral amino acids, basic amino acid, acidic amino acids, amines, purine bases, nucleosides, vitamins and hormones.
The more lipophilic substances that are present in the blood can diffuse passively directly through the lipid of the cell membrane and enter the endothelial cells and brain by this means.
Strategies for Brain Targeting Mechanisms for drug targeting in the brain involve going either "through" or "behind" the BBB.
Neurosurgical or Invasive Strategies
BBB disruption :Disruption of BBB by osmotic means (Hyperosmolar solutions),
Intraventricular drug infusion
Intracerebral Implants: Biodegradable implants,
Physiologic based Strategies
Psuedo nutrients eg L-dopa
Cationic antibodies.These undergo Absorption mediated trancytosis through BBB owing to positive charge.
Chimeric peptides.
Introduction to bipharmaceutics:
Biopharmaceutics: the study of how the
physicochemical properties of drugs, dosage
forms and routes of administeration affect the
rate and extent of the drug absorption.
Thus, biopharmaceutics involves factors that
influence the:
1) protection and stability of the drug within the
product;
2) the rate of drug release from the product;
3) the rate of dissolution of the drug at the
absorption site; and
4) the availability of the drug at its site of action .
Introduction to bipharmaceutics (Cont.):
ADME: is an acronym in pharmacokinetics and
pharmacology for absorption, distribution, metabolism,
and excretion, and describes the disposition of a
pharmaceutical compound within an organism.
Pharmacokinetics: The study and characterization of
the time course (kinetics) of drug absorption, distribution,
metabolism and elimination (ADME)
Absorption: is the process of a substance entering the
body.
Distribution: is the dispersion of substances throughout
the fluids and tissues of the body.
Metabolism: is the irreversible transformation of parent
compounds into daughter metabolites.
Excretion: is the elimination of the substances from the
body.
Bioavailability: The rate and extent of drug absorption.
Bioavailable dose: The fraction of an administered
dose of a particular drug that reaches the systemic
circulation intact.
Acute scrotum is a general term referring to an emergency condition affecting the contents or the wall of the scrotum.
There are a number of conditions that present acutely, predominantly with pain and/or swelling
A careful and detailed history and examination, and in some cases, investigations allow differentiation between these diagnoses. A prompt diagnosis is essential as the patient may require urgent surgical intervention
Testicular torsion refers to twisting of the spermatic cord, causing ischaemia of the testicle.
Testicular torsion results from inadequate fixation of the testis to the tunica vaginalis producing ischemia from reduced arterial inflow and venous outflow obstruction.
The prevalence of testicular torsion in adult patients hospitalized with acute scrotal pain is approximately 25 to 50 percent
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.
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
micro teaching on communication m.sc nursing.pdfAnurag Sharma
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.
Knee anatomy and clinical tests 2024.pdfvimalpl1234
This includes all relevant anatomy and clinical tests compiled from standard textbooks, Campbell,netter etc..It is comprehensive and best suited for orthopaedicians and orthopaedic residents.
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
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
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.
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
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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
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
2 Case Reports of Gastric Ultrasound
3. Content
I. Objectives
II. Introduction
III. Drug Barriers
IV. Physiological Barriers
V. Biochemical Barriers
VI. Chemical and Physicochemical
Barriers
VII. Methods to Overcome Drug Barriers
VIII. Conclusion
IX. Questions
3
4. I. Objectives
By the end of this lecture you will be able to:
1. Realize the impact of drug barriers on the therapeutic
efficacy
2. Identify the main barriers encountered in drug
transport
3. Understand the clinical importance of P-
glycoproteins
4
5. I. Introduction
From many years researchers and scientists are working a lot on the
drug discovery.
Many of the potent drugs have been yet discovered but still the
given drug dose not reach the site of action, especially the drugs
given orally because of barriers
present in body and due to drug properties.
And this problem also persist with biological products like peptides,
proteins etc. 5
6. II. Types of Drug Barriers
6
Barrier
s
PHYSIOLOGICAL
BARRIERS
BIOCHEMICA
L BARRIERS
PHYSICO-
CHEMICAL
PROPERTIES OF
DRUG
CHEMICAL
BARRIERS
7. III. Physiological Barriers
A. Blood Brain Barrier (BBB): is a membrane
that controls the passage of substances from the
blood into the central nervous system.
It is not an absolute barrier but is a site that is less
permeable to more hydrophilic substances than are
most other areas of the body; (98% of small Mwt
drugs and 100% of large Mwt drugs, mainly
peptides and proteins, developed for CNS
pathologies don’t readily cross the BBB).
Excludes ionized substances.
7
8. III. Physiological Barriers
B. Intestinal epithelium: is a single cell layer,
largest and most important barrier against the
external environment.
Weak acids and bases will be absorbed by simple
diffusion to a greater extent in the part of the GI
tract in which they exist in the most lipid-soluble
(non-ionized) form
Hydrophilic substances will be transported to the
liver by the portal vein.
Highly hydrophilic substances may be absorbed
through transporters (xenobiotics with similar 8
9. III. Physiological Barriers
C. Blood Ocular Barrier: is a barrier created by
endothelium of capillaries of the retina and iris.
(Barrier to MOST molecules EXCEPT lipophilic
molecules)
N.B. Passage of molecules results in inflammation &
injury
Example of drugs that can penetrate barrier:
• Antibiotics: Ciprofloxacin – chloramphenicol
• NSAID – SAID
Example of drugs that can NOT penetrate barrier:
• Fluorescine dye (So, it is used to test integrity of
retinal circulation)
• Drugs that bound to plasma proteins
9
10. III. Physiological Barriers
D. Skin: The physical barrier is mainly
located in the stratum corneum and
consists of protein-enriched cells and lipid
enriched intercellular domains.
10
11. IV. Biochemical Barriers
A. Metabolizing enzymes: In the lumen of stomach, a mixture of
hydrochloric acid and proteolytic pepsins is the first metabolic barrier
and the enzymes of the upper small intestine act as second barrier.
B. Transporter and efflux pump: Substrate can be transported
through the brush border membrane in a carrier-mediated and pH-
dependent manner. P-glycoprotein (P-gp) is a known MRP(multi
resistance protein) that serves as an efflux pump.
11
12. IV. Biochemical Barriers
P-glycoprotein
Multidrug resistance protein 1 (MDR1)
Transport various molecules, including xenobiotic, across cell
membrane
Extensively distributed and expressed throughout the body
12
13. IV. Biochemical Barriers
13
Site of Transportation Function
Liver – Bile Elimination
Kidney - Urine Excretion
Placenta – Maternal blood Protect fetal from drug exposure
Intestine – Intestinal lumen Reduce drug absorption into the
blood
Brain – Blood Monitor drug access to the brain
Function of P-glycoprotein
14. IV. Biochemical Barriers
Role of P-gp is significant in tumor cells.
Expression of P-gp in tumor cells reduces the accessibility of
cytotoxic drugs by eliminating them in various pathways. Hence, P-gp
may act as a major barrier to effective drug treatments.
Over expression of P-gp limits the treatment for cancer, AIDS,
Alzheimer’s and epilepsy.
14
Clinical Importance of P-glycoprotein
17. V. Chemical Barriers
Hydrogen Bonding Potential
A hydrogen bond is the attractive force between the hydrogen
attached to an
electronegative atom of one molecule and an electronegative atom of
a different molecule.
Hydrogen bonding is a key contributor to the specificity of
intramolecular and
intermolecular interactions in biological system. 17
18. VI. Physicochemical Properties of Drugs
Physicochemical properties of drug are also important determinants
in the passage of drugs via the para-cellular path.
The physicochemical properties such as solubility, ionization,
lipophilicity, permeability, etc. are important for determination of
drug action.
18
19. VII. Methods to Overcome Drug Barriers
1.PHYSICAL METHODS
External stimuli are applied to open the barrier it includes
ultrasound, iontophoresis, stripping etc.
Ultrasound, microwave or electromagnetic fields that can be used to
open the blood brain barrier.
Microwave irradiation facilitated central effects of domperidone by
altering the permeability of blood brain barrier and enhancing the
entry of drug into the CNS.
19
20. VII. Methods to Overcome Drug Barriers
1.PHYSICAL METHODS
Stripping is a technique used to remove stratum corneum by
application of adhesive tape or cyanoacrylate Glue.
Iontophoresis and electroporation require electrical forces for drug
delivery across stratum corneum.
20
21. VII. Methods to Overcome Drug Barriers
2. CHEMICAL METHOD
Chemical method involves the use of chemicals to increase the permeability
of the barrier.
A large number of absorption enhancers have been studied, such as fatty
acids, bile salts, enamine derivatives of phenylglycine, esters, ethers,
salicylates.
Mostly used blood brain barrier opening practice is via arterial injection of
hyperosmolar solution (e.g. mannitol, arabinose).
Chemical enhancers for skin include the compounds that interact with the
lipid matrix of the stratum corneum to alter its nanostructure and thereby 21
22. VII. Methods to Overcome Drug Barriers
2. CHEMICAL METHOD
The most common chemical enhancer is water, which leads to
hydration of the stratum corneum.
Solvents, such as ethanol, methanol, chloroform and acetone, as well
as detergents increases the permeability of stratum corneum.
22
23. VII. Methods to Overcome Drug Barriers
3. BIOCHEMICAL METHOD
Biochemical method involves the biological molecule as permeability
enhancer.
A 45 kDa biological molecule zonula occludens toxin (Zot), an active tight
junction modulator at the blood brain barrier.
It also permits an enhanced transport of the therapeutic agents doxorubicin
and paclitaxel.
Magainin, a naturally occurring pore-forming peptide increase skin
permeability by direct interaction with and disruption of stratum corneum 23
24. VII. Methods to Overcome Drug Barriers
4. DRUG DELIVERY BY FORMULATIONS
COLLODIAL DRUG CARRIERS: include micelles, emulsions, liposomes
and nanoparticles.
BIODEGREDABLE NANOPARTICLES: formulated from poly (D,L-
lactide-co-glycolide) (PLGA) are used for sustained and targeted
delivery of different agents including plasmid DNA, proteins and
peptides and low weight molecules.
24
25. VII. Methods to Overcome Drug Barriers
4. DRUG DELIVERY BY FORMULATIONS
LIPOSOMES: Liposomes are small vesicles that are composed of
unilamellar or multilamellar phospholipids bilayers surrounded by
aqueous compartments.
PRODRUG: The prodrug are used to overcome various barriers which
can hinder drug delivery, including solubility.
25
26. VIII. Conclusions
26
The absorption of an orally administered drug depends on its passage
through several barriers to deliver drug. The drug can pass either between or
through the cells, depending on its physicochemical properties.
Overcoming these barriers help in the development of improved drug
delivery systems to treat different diseases conditions.
Although many challenges exist in transporting the drug from different
barriers, that’s why pharmaceutical scientists and medicinal chemists are
overcoming them with new drug delivery system that enhance drug delivery.
28. 1. With respect to the BBB, Which of the following is/or true ?
a. Limits the passage of approx. 100% of large molecular weight molecules
b. Excludes ionized substances
c. Active transport is considered
d. All of the above
2. A Method (s) used to overcome the BBB?
a. Ultrasound
b. Microwave irradiation
c. Both a and b
d. Stripping
28
29. 3. For a drug to be passively transported through the GI tract, it requires to be
a. Ionized and hydrophobic
b. Non-ionized and hydrophilic
c. Non-ionized and hydrophobic
d. None of the above
4. All of the following are true about the blood ocular barrier Except,
a. Barrier to most molecules except hydrophilic molecules
b. Barrier to most molecules except lipophilic molecules
c. NSAIDs can penetrate
d. Drugs bound to plasma proteins can not penetrate
29
30. 5. For transdermal drug delivery, which of the following is/are regarded as the major
barrier (s)?
a. Epidermis
b. Stratum corneum
c. Dermis
d. None of the ab
6. A naturally occurring pore-forming peptide increase skin permeability by direct
interaction with and disruption of stratum corneum lipids?
a. Magainin
b. Zonula occludens toxin (Zot)
c. All of the above
d. None of the above
30
31. 7. Mostly used blood brain barrier opening practice is
a. Arterial injection of hyperosmolar solution
b. Injection of mannitol
c. Injection of arabinose
d. All of the above
8. The permeability of skin barrier could be chemically enhanced using
a. Iontophoresis
b. Absorption enhancers such as bile salts
c. Stripping
d. None of the above
31
32. 9. Regarding P-glycoprotein, which of the following is/are correct?
a. Regarded as a Biochemical barrier
b. Known as multidrug resistance protein 1
c. Overexpressed in tumor cells and
d. All of the above
10. Drug delivery barriers could be overcome using advanced formulations such as
a. Prodrugs
b. Colloidal systems
c. Nanoparticles
d. All of the above
32