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There are suspensions that can be either flocculated or deflocculated. The main difference between flocculated and deflocculated suspension is that the rate of sedimentation in a flocculated suspension is rapid whereas the rate of sedimentation in a deflocculated suspension is slow.
Which is desirable suspension?
Desirable properties of suspensions are that they should have good organoleptic properties, suspensions should possess good pourability leading to ease of removal of dose from container, the particle size distribution should be uniform, there should be ease of re dispersion of settled solid particles, they should be Dec 8, 2015
Which type of suspension have relatively greater bioavailability?
h/mL) were significantly greater compared with fasting (p < 0.0001). Conclusions: This study has shown that the new atovaquone oral suspension also has significantly greater bioavailability when administered after food or a nutrition supplement that has a moderate fat content.
What are the disadvantages of suspension?
v) Drug in suspension exhibits a higher rate of bioavailability compared to the same drug of equivalent dose formulated in tablets or capsules. This is due to larger surface area and high dissolution, e.g., antacid suspension. 1. Sedimentation of solids occasionally gives poor form of product.
Why are suspending agents used?
2. SUSPENDING AGENTS Suspending agents also called thickening agents are used to stabilize suspensions are hydrophilic colloid i.e. substances that spontaneously form colloidal dispersions with water because of an affinity between the dispersed particles and the dispersion medium.
What are the differences between flocculated and non flocculated suspension?
The suspension are said to be flocculated ,when the individual particles are in contact with each other and form a network like structure . Whereas in case of non-flocculated suspensions,the individual particles exists as a separate entity. In Non-flocculated suspensions The rate of sedimentation is slow.
What are the advantages of suspension?
The following advantages can be obtained by formulating API as a suspension dosage form.
- Suspensions are a useful drug delivery system for therapeutic agents that have a low solubility.
- Pharmaceutical suspensions may be formulated to mask the unpleasant/ bitter taste of drug.
What are suspending agents?
: a substance (such as carrageenan, xanthan gum, or cellulose ether) that is added to fluids to promote particle suspension or dispersion and reduce sedimentation All these drinks can contain preservatives, and drinks other than juices can contain additives to colour, flavour and sweeten.
Why is flocculated suspension better?
There are suspensions that can be either flocculated or deflocculated. The main difference between flocculated and deflocculated suspension is that the rate of sedimentation in a flocculated suspension is rapid whereas the rate of sedimentation in a deflocculated suspension is slow.
What is the first pass effect and bioavailability?
The first-pass metabolism or the first-pass effect or presystemic metabolism is the phenomenon which occurs whenever the drug is administered orally, enters the liver, and suffers extensive biotransformation to such an extent that the bioavailability is drastically reduced, thus showing subtherapeutic action (Chordiya
Which drug has highest bioavailability?
Drug: Propranolol- ~26% Bioavailability because 75-85 % is metabolized by the liver before it can reach the circulation when taken orally. Drug: Morphine-~30% Bioavailability because 70% is metabolized via 1st pass effect if taken orally.
What is the advantage of independent suspension?
Independent suspension typically offers better ride quality and handling characteristics, due to lower unsprung weight and the ability of each wheel to address the road undisturbed by activities of the other wheel on the vehicle.
What is good quality suspension?
1 It should settle slowly and should be readily re-dispersed on gentle shaking of the container. 2 The particle size of the suspension remains fairly constant throughout its long period of undisturbed standing . 3 The suspension should pour readily and evenly from its container.
How do you make suspension drugs?
Gently shake the bottle to loosen the powder. Open the cap. Carefully add cool boiled water to about half the height of the final marking on the bottle.
Why do Flocculated particles not cake?
Repulsive forces between particles are overcome and a hard cake is formed which is difficult, if not impossible, to redisperse. The sediment is loosely packed and possesses a scaffold-like structure (large volume of final sediment). Particles do not bond tightly to each other and a hard, dense cake does not form.
What does Flocculated mean?
The process by which individual particles of clay aggregate into clotlike masses or precipitate into small lumps. Flocculation occurs as a result of a chemical reaction between the clay particles and another substance, usually salt water.
What do you mean by flocculated suspension?
A flocculated suspension is a suspension in which particles of the suspension has undergone flocculation. Flocculation is the process in which colloids in a suspension can be obtained in an aggregated form.
How Deflocculation is different from flocculation?
The key difference between flocculation and deflocculation is that flocculation is the formation of flocs by the clumping of fine particles, whereas deflocculation is the dispersion of flocs to form a stable colloid. Flocculation refers to the formation of clumps from fine particles in a colloid.
Which form of drug has highest bioavailability?
Thus having the highest bioavailability. Tablets take time to disintegrate. The order of decreasing bioavailability will be, solutions > emulsions > suspensions > capsules > tablets > coated tablets > enteric coated tablets>sustained released products. 4.
What is needed for good bioavailability?
For FDA approval, a generic manufacturer must demonstrate that the 90% confidence interval for the ratio of the mean responses (usually of AUC and the maximum concentration, Cmax) of its product to that of the “brand name drug” is within the limits of 80% to 125%.
What increases drug bioavailability?
The main mechanisms that have been identified through which bioenhancers can improve the bioavailability of drug molecules include alteration of the plasma membrane fluidity to increase passive transcellular drug permeation; modulation of tight junctions to allow for increased paracellular diffusion; and active efflux Jan 16, 2019
What is the disadvantage of suspension bridge?
There is less flexibility with a suspension bridge. This disadvantage causes them to not remain sturdy under high wind conditions unless reinforcements are built into the structure.
How suspension improves the stability of drugs?
There are some useful methods to improve the physical stability of a suspension, such as decreasing the salt concentration, addition of additives to regulate the osmolarity, as well as changes in excipient concentrations, unit operations in the process, origin and synthesis of the drug substance, polymorphic behavior
Is darvan a flocculant?
In ceramics, there are a number of different deflocculants available. Darvan is a liquid deflocculant that is often preferred for use with plaster molds because, unlike some other deflocculants, Darvan does not degrade the plaster.
Is Vinegar a Deflocculant?
Vinegar is often used in ceramic slurries to change the viscosity (thicken it). While there are more effective flocculants (e.g. calcium chloride, epsom salts), vinegar is popular among potters simply because it is so available.
