Explore topic-wise InterviewSolutions in .

Right answer is (a) The TUBE is made up of stainless steel

Easy explanation: The innermost drug reservoir is contained in an IMPERMEABLE POLYESTER bag. The outermost RIGID rate controlling semipermeable MEMBRANE. A rigid polymeric plug is used to form a leak-proof seal between the drug and the semipermeable housing. The tube is made up of stainless steel.

The correct option is (c) The drug is contained a permeable POLYESTER BAG

The BEST I can explain: The pump is MADE of three concentric layers. The innermost reservoir is contained in a collapsible impermeable polyester bag. The OUTERMOST is a rigid, rate controlling semipermeable membrane made from substituted cellulosic polymers.

The correct choice is (a) Nonimmunogenic

Best explanation: In this system, the DRUG is loaded in the body’s own erythrocytes and used to serve as a controlled drug DELIVERY system. These are FULLY biodegradable, nonimmunogenic. They can circulate transvascularly for days and will allow a LARGE number of drugs to be carried.

Right choice is (d) Drugs, peptides, viruses, bacteria

The explanation: A large variety of drugs, peptides or proteins including antibodies and viruses and bacteria can be incorporated into liposomes. Water-SOLUBLE drugs will be TRAPPED in the aqueous COMPARTMENT while the lipophilic ones are incorporated in the LIPID phase of liposomes. They are available in various sizes and have the ability to incorporate both water and lipid soluble drugs.

Correct answer is (c) Lipid bilayer enclosing the drug

Easy explanation: It is defined as the vesicle of lipid bilayers enclosing an aqueous compartment. Most COMMONLY phospholipids, SPHINGOLIPIDS, glycolipids are used to prepare liposomes. Their SIZE ranges from 25 to 5000 nm. A large variety of drugs, peptides or proteins INCLUDING antibodies and VIRUSES and bacteria can be incorporated into liposomes.

The CORRECT OPTION is (d) SIZE range 10-100 nm

For explanation I would say: Nanoparticles are called as nanospheres when the drug is in the polymer matrix and nanocapsules when they are encapsulated. They DIFFER from microspheres to nano size with size 10-1000nm. The polymers used are BIODEGRADABLE ones.

Correct answer is (b) Drug RELEASE can be increased by increasing viscosity

For EXPLANATION: The release of drugs from aqueous solutions can be increased by increasing the viscosity of the VEHICLE by use of MC, CMC, and PVP. By forming a COMPLEX with macromolecules. By forming a complex that controls drug release.

The CORRECT answer is (C) Control drug release by partitioning the drug from the oil

Easiest EXPLANATION: Oil solutions control release by partitioning the drug out of the oil in the surrounding aqueous fluids. Vegetable oils such as arachis oil, cottonseed oil, ETC. can be used for this. The method is used for only drugs which are lipid soluble and have an optimum partition COEFFICIENT.

Correct choice is (a) Free flowing powders

The explanation: Microspheres are free flowing powders consisting of spherical particles of size less than 125 MICRONS which can be suspended on a suitable aqueous vehicle. This SOLUTION can then be injected by 18-20 NUMBERS of injections. Each particle is a MATRIX of drug dispersed.

Right option is (a) Slower

Easy explanation: Larger the PARTICLE size slower the dispersion since the surface area to volume ratio is less. ALTHOUGH large particles have their own disadvantages such as causing irritation at the injection site, poor syringeability and injectability, and RAPID sedimentation. We can use VISCOSITY builder but this also retards drug diffusion.

Right option is (d) Increasing the pH to make it highly basic

Best explanation: Both aqueous and oil solutions can be used for controlled DRUG release. The aqueous solution the release can be controlled by increasing the viscosity of the vehicle by USE of MC, CMC, PVP. BY forming complexes with MACROMOLECULES like MC, CMC, or PVP. By forming complexes that control drug release not by dissociation but by reducing the solubility of the parent drug.

Right option is (b) Consists of PYROGEN

The explanation is: The VEHICLE, polymers, and other substances which are used in parenteral formulations must not CONTAIN any pyrogen, sterile, non-irritating, BIOCOMPATIBLE and biodegradable into nontoxic compounds WITHIN the time preferably close to the duration of drug action.

Right option is (d) Day, WEEK, month EVEN a year

For explanation: The advantages of parenteral admiration is the duration of action can be extended for days, weeks, months or even a year. The major drawback of parenteral administration is once the administration is done, the drug cannot be removed easily if an undesirable action happens. These drugs are administered by subcutaneous, intramuscularly, INTRAVENOUS, intraperitoneal.

Correct choice is (C) Usage of polymers that dissolves only in the alkaline PH of COLON

Explanation: For the drug to be released in colon pH sensitive bio erodible polymers like polymethacrylates are used. These polymers release the MEDICATION only at the alkaline pH of colon. These are used for the treatment of ulcerative colitis. Also can use divinylbenzene polymers which will be CLEAVED by azoreductase.

Right option is (d) Use of enteric coating

To explain: A drug to make it release only in the intestine are enteric coated. The reason of such drugs to PREVENT GASTRIC IRRITATION, prevent destabilisation in gastric PH. Selective release of the drugs to Peyer’s patch of intestine prevents them from getting destroyed by the intestinal enzymes.

Correct CHOICE is (b) False

The best EXPLANATION: Drugs are poorly absorbed through the colon but can be delivered to the colon. It is used for the treatment of ulcerative colitis, systemic absorption of insulin and vasopressin LIKE peptides. ALSO can USE divinylbenzene polymers which will be cleaved by azoreductase.

Right answer is (c) Usage of bio adhesive polymer

Best explanation: Bio adhesive polymers when they are used as a CROSS linked polyacrilic acid and are INCORPORATED in a tablet, it allows it to adhere to the gastric mucosa or epithelium. Such a system continuously releases a fraction of drug into the INTESTINE over prolonged PERIOD of TIME increasing the pharmaco therapeutic time.

Correct CHOICE is (d) Use of HIGH or LOW density pellets

Easiest explanation: The GI transit TIME is less than 24 hrs. Thus the density of the drugs changes such that the frequency of dosing can be REDUCED. The use of altered density approach use either high or low density pellets. These are hydrodynamically balanced systems. Titanium dioxide, barium sulphate can be used to increase the density.

The correct choice is (b) Granule drug with hydro gel

To explain: Floating of buoyant capsules are FORMULATED by granulating a drug with 20-80% of hydrogel. On contact with the GI FLUIDS these tablets swells and forms a diffusible gel that lowers the density of the system allowing it to float. Or a gas filled floatation chamber can be ATTACHED to a MEMBRANE coated tablet for making it buoyant.

Right answer is (c) Hydrodynamic pressure controlled system

The explanation is: Hydrodynamic controlled SYSTEMS are generated by swelling of a hydrophilic gum which will be further used to activate the delivery of drugs. The device comprises of a rigid, shape retaining hosing enclosing a collapsible COMPARTMENT CONTAINING the drug. Such systems are ALSO known as push-pull osmotic pumps.

Right choice is (a) Oral osmotic pump

Explanation: An oral osmotic pump works on the PRINCIPLE of osmotic pressure to release drug at a constant zero order rate. The CORE comprises of the drug and osmotically ACTIVE substances such as potassium chloride or mannitol. This is again SURROUNDED by a rigid semi permeable membrane coating such as cellulose ester.

The correct CHOICE is (b) Reservoir device

The explanation: Reservoir devices are hollow containing an INNER core of drug which will be SURROUNDED in a water insoluble polymer membrane. The polymer can be applied by coating or microencapsulation techniques. The drug release mechanism across the membrane involves its partitioning into the membrane with subsequent release INT o the surrounding fluid by DIFFUSION.

Correct choice is (d) Swellable matrix

The best I can explain: Swellable matrix SYSTEMS are popular for sustaining the RELEASE of HIGHLY water soluble drugs. The materials for such matrices are generally hydrophilic gums such as GUAR gum, polyacrylamide etc. The drug and gum are granulated TOGETHER with a solvent and then are compressed into tablets.

Correct CHOICE is (c) Rigid matrix

The best EXPLANATION: Rigid matrix are made up of PLASTICS such as PVC or fatty acids such as STEARIC acid or bees wax. The drug is generally kneaded with the SOLUTION in an organic solvent and then granulated. Waxy matrix are prepared and then compressed into tablets.

The correct ANSWER is (b) Encapsulated system

Explanation: The drug PARTICLES are encapsulated with slowly dissolving particles such as cellulose, PEG, waxes etc. The resulting pellets MAY be filled in hard gelatin capsules or compressed into tablets. The DISSOLUTION RATE of the coat depends upon the solubility and thickness of the coating.

Right answer is (c) Generated by SWELLING hydrophilic hum

For explanation: In hydrodynamic pressure controlled systems we USE the hydrodynamic pressure generated by swelling a hydrophilic gum. The FORMULATION comprises of rigid, shape-retaining HOUSE enclosing a collapsible, impermeable compartment containing the liquid drug. The systems are also called push-pull osmotic pumps.

Right option is (B) False

Best explanation: Osmotic pressure controlled systems are formulated such that they RELEASE the drug constantly at a zero order rate. The CORE comprises of the drug and an osmotically active substance such as POTASSIUM chloride or mannitol which will be SURROUNDED by a rigid semipermeable membrane coating such as ester or cellulose ester.

Right option is (b) Releases the drug at a zero-ORDER kinetics

To explain I would say: Osmotic pressure-controlled systems works on the PRINCIPLE of osmotic pressure to release the drug at a constant zero order RATE. The core of the system comprises of the drug and osmotically active SUBSTANCE which will be surrounded by a rigid semipermeable membrane coating.

Correct answer is (a) BUFFERING agents that adjust pH to the desired value

For EXPLANATION I would say: pH INDEPENDENT formulations are designed such that they can eliminate any changes in the drug property by the CHANGING GI pH. This is done by formulating them with sufficient amount of buffering agents such as phosphoric ACID, tartaric acid, citric acids. These formulations adjust the pH to the desired value.

The correct answer is (d) Formation of complexes between the drug and anion/cation EXCHANGE resins

Easiest explanation: Ionisable acidic and basic DRUGS are complexed with insoluble anion or cation exchange resins. The drug is released slowly by diffusion through the resin PARTICLE. Thus the controlled released of the drug is MAINTAINED. Drugs such as noscapine have been utilized by such METHODS.

Right option is (C) Hollow systems containing drug SURROUNDED by a polymer membrane

The explanation: These systems are hollow which CONTAINS an inner core of drug surrounded in a water-insoluble polymer membrane. The drug release MECHANISM involves partitioning into the membrane with subsequent release into the surrounding fluid by diffusion.

Right choice is (b) Drug DISPERSE in an insoluble MATRIX of rigid HYDROPHOBIC materials

The best I can explain: In this system, the drug is dispersed into an insoluble matrix of a rigid nonswellable hydrophobic material or swellable hydrophilic material. Materials such as insoluble plastic PVC and FATTY ACIDS are used as rigid matrix. The drug is generally kneaded with the plastic material.

Correct answer is (a) Microencapsulation using slowly dissolving materials

Best explanation: When drugs are encapsulated with slowly dissolving materials such as that of CELLULOSE, PEG, waxes, ETC. The pellets may be filled up in hard gelatin capsules and then compresses to FORM into tablets. The dissolution rate of the coat depends upon the SOLUBILITY and THICKNESS of the coat.

Correct answer is (B) Diffusion of the dissolved drug

For explanation: The rate controlling step is the diffusion of the dissolved drug through a polymeric barrier. The drug release rate is never 0. The diffusional path length increases with TIME as the insoluble MATRIX gradually depletes from the drug. Two types of diffusion-controlled SYSTEMS are matrix systems and reservoir systems.

The correct option is (d) Employ waxes to control the rate of dissolution

Easy explanation: MATRIX drugs are homogenous drugs since they are dispersed throughout the drug in a rate CONTROLLING medium. They employ wax such as beeswax, hydrogenated CASTOR oil, ETC. the drug is OFTEN first order from such matrixes. The wax embedded drug is prepared by dispersing the drug in molten wax and granulating it.

The correct option is (d) Very slow dissolution rate

To explain: Dissolution controlled RELEASE system is easiest to DESIGN. The drug of such system may be inherently slow dissolution, such drugs ACT as natural prolonged release products. These drugs form slow DISSOLVING forms when it comes in contact with GI fluids. These drugs have HIGH aqueous solubility.

Right option is (c) Release only at a SPECIFIC DRUG

To EXPLAIN: The design of delayed release systems involves the release of the drug only at a specific site in the GIT. The drugs which are included in such system are destroyed in the stomach or by intestinal ENZYMES. These drugs are known to gastric distress and absorbed from a specific intestinal site.

Correct option is (B) Prolonged their residence in the GIT and release

For EXPLANATION: Delayed TRANSIT and CONTINUOUS release systems are designed to prolong their residence in the GIT along with the increase of releasing time. Most of the time the dosage form is fabricated to retain in the stomach and HENCE the drug present therein should be stable at gastric pH.

Right OPTION is (b) False

To explain I WOULD say: Continuous release SYSTEMS release the drug for a prolonged period of time. The drug will be releasing components along the whole length of the GIT with normal TRANSIT of the dosage form. It releases the drug especially up to the TERMINAL region of the small intestine.

Right CHOICE is (a) Glatiramer acetate

Explanation: Glatiramir acetate is a KNOWN medicine for multiple sclerosis. Glatiramir acetate is believed to modify the immune process that causes multiple sclerosis. The most important TREATMENT of this disease is to decrease the influence of the immune system so that no more myelin ANTIGENS are produced.

The correct answer is (a) Betaseron

Explanation: Beta 1-b is interferon. Betaseron diminishes the activity of specific WBCs causing disease. Since MS is not curable so all the TREATMENTS are there to slow the PROGRESSION of the disease. This medicine DECREASES the WORKING of the specific WBCs.

Correct choice is (c) Produced by activated NK cells

To explain: Gamma which is immune interferon is produced by certain activated T cells & NK cells. ALPHA which is leukocyte interferon is produced by virus-infected leukocytes. BETA FIBROBLAST interferon is produced by virus-infected fibroblasts or epithelial cells.