Delivery Of Theophylline Microcapsules To The Colon Biology Essay al. , “ Time and pH dependent colon particular, pulsatile bringing of Elixophyllin for nocturnal asthma. ” The present survey demonstrated a modified chronopharmaceutical preparation based on clip and pH for the bringing of Elixophyllin microcapsules to the colon. The formulated system consisted of an indissoluble difficult gelatin capsule organic structure which was filled with Elixophyllin microcapsules and sealed with a hydrogel stopper like cluster bean gum, HPMC and Na alginate. For get the better ofing the variableness in stomachic voidance clip, the full device was coated with an enteral polymer.

Andrea al. , “ Oral pulsatile bringing systems based on swellable hydrophilic polymers ” In this survey, the assorted hydrophilic polymers used in the different pulsatile release preparations like reservoir, capsular and osmotic preparations were studied. The H2O swellable polymers particularly polysaccharidic compounds have been exploited to the greatest extend in the delayed release preparations. These hydrophilic polymers have shown to successfully supply a lag stage required, by undergoing swelling, disintegration or eroding procedure and therefore enabling its usage in chronotherapeutic attacks.

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Mohammad al. , “ Propranolol hydrochloride osmotic capsule with controlled oncoming of release ” Propranolol hydrochloride osmotic capsule was formulated and evaluated. The system consisted of an difficult gelatin capsule coated with ethyl cellulose with or without castor oil and was filled with propranolol hydrochloride along with sorbitol which functioned as an osmotic agent. Beeswax stopper was used for sealing the capsule organic structure. The assorted factors like membrane thickness, stopper thickness, concentration of cellulose ethanoate and Castor oil was besides studied and the system was found to be utile for chronotherapeutic intents.

Sindhu al. , “ Development of modified pulsincap drug bringing system of Flagyl for drug targeting ” The formulated design consisted of a methanal treated hard gelatin capsule incorporating the metronidazole pellets and plugged with polymers like cluster bean gum, HPMC-10K, carboxymethylcellulose Na and Na alginate at different concentrations. The prepared capsules were farther coated with an enteral polymer and a lag clip of approximately 5 hour was obtained.

Usha Yogendra al. , “ Chronotherapeutic drug bringing for early forenoon rush in blood force per unit area: A programmable bringing system ” The survey involved the preparation of a system which contained a swellable polymer like xanthan gum, Na alginate, L-HPC or poly ethylene oxide along with the drug ( Diovan ) tablet and an erodible tablet of L-HPC or guar gum in a pre coated capsule. The drug release was influenced by the type and sum of polymers and besides the erodible tablet. Everted rat enteric section was used for the disintegration – soaking up survey and it indicated a successful hold in soaking up of the drug.

Hong-Liang al. , “ Release features and in vitro-in vivo correlativity of pulsatile form for a pulsatile drug bringing system activated by membrane rupture via osmotic force per unit area and swelling ” The performed survey demonstrated that for a Pulsatile drug bringing system based on the rule of membrane rupture, the nucleus and the coating preparation influences the release profile. The thickness, hydrophilicity and the osmotic consequence of the semi permeable membrane and the swellability of the excipients determined the lag clip of the system. Besides the add-on of a hydrophilic plasticiser showed a lessening in the slowdown clip.

Akhgari, F. al. , “ Combination of time-dependent and pH-dependent polymethacrylates as a individual coating preparation for colonic bringing of indomethacin pellets ” In this survey a combination of two pH dependent polymers ( Eudragit S100 and Eudragit L100 ) and a clip dependent polymer ( Eudragit RS ) was used for planing a preparation for the bringing of indomethacin pellets to the colon. The lag clip of the system was affected by the surfacing degree and its optimum was found to be 10 % .

T.Y. al. , “ An probe of pulsatile release tablets with ethylcellulose and Eudragit L as movie coating stuffs and cross-linked polyvinylpyrrolidone in the nucleus tablets ” In the present survey, the system formulated for the pulsatile bringing of Cardizem hydrochloride consisted of a coating of ethyl cellulose and Eudragit L and cross linked poly vinyl pyrrolidone was employed as the swelling agent. The PH of above 6 caused Eudragit L to fade out and created pores in the coating through which H2O permeated and caused the enlargement of the swelling agent which resulted in the burst release of the drug. The in vivo survey showed good correlativity with the in vitro informations.

Ina al. , “ Pulsatile drug release from an indissoluble drug organic structure controlled by an erodible stopper ” The formulated system consists of an impermeable capsule organic structure lodging the drug and an erodible stopper which is prepared by either direct compaction or by the congealing of a disintegrable stopper stuff. With increasing molecular weight of the hydrophilic stopper stuff and diminishing concentration of the filler, the eroding clip increased. Congealable lipid stoppers and wetting agents decreased the eroding clip. The consequence of assorted excipients like sparkling agents on the rapid release of drug was besides demonstrated.

Pedro R. al. , “ Influence of adjuvants on the in vitro disintegration of Microzide from difficult gelatin capsules ” The purpose of the survey was to find the influence of assorted excipients like fillers, lubricators and wetting agents on the disintegration of Microzide from difficult gelatin capsules. The preparations with no wetting agent showed the lowest disintegration profile. The greatest consequence on the disintegration profile was due to lubricators and so by the filler. Hydrophobic lubricators like Mg stearate showed lesser disintegration efficiency than aerosil. Though both micro crystalline cellulose and milk sugar are hydrophobic, because of the H2O incorporation belongings of the micro crystalline cellulose, it showed better disintegration efficiency than milk sugar.

Rebecca L. al. , “ The public-service corporation of cyclodextrins for heightening unwritten bioavailability ” The ability of I?- cyclodextrin to heighten the unwritten bioavailability of drugs was examined in this survey. The complexation of the drug with I?- cyclodextrin improved the bioavailability better than the physical mixture. The disintegration and soaking up of the inclusion composite was found to be related to the physical and chemical belongings of the drug, I?- cyclodextrin and besides the dose signifier. al. , “ Different HPMC viscousness classs as coating agents for an unwritten clip and/or site-controlled bringing system: a survey on procedure parametric quantities and in vitro public presentations ” The survey involved the development and optimisation of a preparation devised to let go of drug after a lag clip or to present the drug to the colon utilizing different classs oh HPMC. MethocelA® E50 was found to be the better hydrophilic polymer as it was least affected by the concentration of the surfacing solution, medium pH and ionic strength.

Julie al. , “ The tolerability of multiple unwritten doses of Pulsincap TM capsules in healthy voluntaries ” The peformed survey was double-blind and had a placebo-controlled analogue group. Twelve healthy topics were involved in the survey of which eight topics were given Pulsincap TM capsules and four topics were given a fiting placebo capsule. The eight topics who received the Pulsincap TM capsules showed no grounds of inauspicious events and the preparation was good tolerated. The consequences of the survey showed that Pulsincap TM capsules can be formulated for the bringing of curative agents.

Howard N.E. al. , “ Evaluation of Pulsincapa„? to supply regional bringing of dofetilide to the human GI piece of land ” The survey was designed to explicate a bringing system to let go of dofetilide, a good absorbed drug following a 5hr hold or to aim its release to the lower GI piece of land. Dofetilide showed a reduced bioavailability when delivered from the Pulsincapa„? preparations. The site of drug release and in vitro in vivo correlativity was determined from the scintigraphic analysis.

T. al. , “ A pulsatile drug bringing system based on rupturable

coated difficult gelatin capsules ” In the present survey, the system formulated consisted of a difficult gelatin capsule which was coated foremost with a swelling bed, and so with an outer indissoluble water-permeable polymer. The lag clip increased with increasing surfacing thickness and decreased on the add-on of a hydrophilic pore former. The swelling caused due to the H2O immersion through the outer polymer resulted in the rupturing of the coating and there by the drug release. The extent of medium consumption was about the same for the different coating degrees. The add-on of the hydrophobic particulate stuff to the coating resulted in a decreased slowdown clip.

Jason T. Mc al. , “ The consequence of wet granulation on the eroding behaviour of an HPMC-lactose tablet, used as rate commanding constituent in a pulsatile drug bringing capsule preparation ” In the survey it was demonstrated that the HPMC tablets prepared by wet granulation showed longer slowdown times compared to those prepared by direct compaction. This was more outstanding at low concentrations of HPMC. Microwave dielectric analysis was used for finding the grade of polymer spreading in the aqueous system. al. , “ Evaluation of the puffiness, hydration and tearing belongingss of the swelling bed of a rupturable pulsatile drug bringing system ” The survey exhibited a additive correlativity between the H2O consumption and the swelling bed. The ionic strength and the pH of the medium was shown to act upon the swelling behaviour of Ac-Di-Solw which was due to the acidic nature of the polymer and the competition for free H2O. The analysis of the clip dependent swelling force informations confirmed that the incursion rate of the medium controlled the diffusion controlled swelling force development.

Gordon L. al. , “ Pharmacokineticss of an immediate release, a controlled release and a two pulse dose signifier in Canis familiariss ” In the present survey, for each dose form the pharmacokinetic parametric quantities were determined. On comparing the plasma clip curves, it was found that there was a important difference in the drug plasma degrees for each dose signifier. For each dosage between 1 – 1.75 and 2.5 – 3.5 hour, two defined Cmax values were obtained.

Roland al. , “ Floating or pulsatile drug bringing systems based on coated effervescent nucleuss ” In the present survey it was demonstrated that the clip of flotation depended on factors like the concentration of the effervescent agent, the type of filler, hardness of the nucleus tablet and the thickness and composing of the polymer like the type of polymer and plasticiser used. In order to ease a rapid drug release after the slowdown stage, a speedy release nucleus was formulated. The lag clip increased with increasing surfacing degree and nucleus hardness.

Joseph al. , “ Responsive polymeric bringing systems ” In the present survey, the cardinal rules of the ego regulated bringing systems and the externally regulated bringing systems were studied. Harmonizing to the physiological demand these systems are capable of seting the release rate of the drugs. The advantages and disadvantages of the different attacks harmonizing to the different clinical conditions like diabetes were besides evaluated.

Ross al. , “ Chronopharmaceutical drug bringing from a pulsatile capsule device based on programmable eroding ” The present survey involved the development of a pulsatile drug bringing device which consisted of an indissoluble capsule organic structure incorporating the drug preparation ( propranoloI hydrochloride ) and sealed with an erodible tabet. With the increasing concentration of dibasic Ca phosphate ( indissoluble excipient ) and HPMC ( gel-forming excipient ) , the slowdown clip was besides found to increase. The clip release was influenced by the composing and weight of the erodible tablet. The formulated system can be used for the development of a chronopharmaceutical bringing system with a slowdown clip runing from 2-12 hour by pull stringsing the erodible tablet preparation.

Bjorn al. , “ Circadian beat and drug bringing ” The maps of the organic structure are found to follow circadian beat eg. Blood force per unit area, bosom rate, blood flow, pneumonic, hepatic and nephritic maps. Therefore the oncoming of diseases and besides their symptoms show a fluctuation within the 24 hour of a twenty-four hours. The pharmacokinetics and pharmaco-dynamics of the different drugs like anti-asthmatics, H-2 blockers and cardiovascular drugs besides show day-to-day fluctuation. So it can be summarized that while measuring a drug bringing system, the biological beat of the organic structure maps has to be taken into history.

Hermida al. , “ Administration-time-dependent effects of antihypertensive intervention on the circadian form of blood force per unit area ” The survey was performed to develop a methodological analysis for the intervention of high blood pressure taking into history the circadian blood force per unit area form. The difference in the clip of disposal of a drug has shown a difference in its anti-hypertensive action. Nifedipine GI curative system showed better anti-hypertensive action and a important decrease in blood force per unit area when administered at bedtime than when compared to the early forenoon disposal.

Nayak al. , “ Chronotherapeutic drug bringing for early forenoon rush in blood force per unit area: a programmable bringing system ” The aim of the survey was to explicate a pulsatile bringing system for Diovan. . The formulated system contained swellable polymer like L-HPC, polythene oxide, xanthan gum or Na alginate along with the drug tablet and an erodible tablet ( L-HPC or guar gum ) enclosed in a pre-coated capsule. The assorted preparation parametric quantities were investigated. The drug release was influenced by the type and sum of polymers and the erodible tablets. A delayed soaking up of drug was observed from the uninterrupted dissolution-absorption survey performed utilizing everted rat bowel.

Ishino R et al. , developed a dry-coated tablet with a pulsatile drug release profile to accomplish a time-controlled and site specific bringing of the drug to the GI piece of land. The formulated bringing system consisted of a permeableness controlled outer shell with a swellable nucleus tablet. The drug was released quickly after a certain period of slowdown clip because of the time-controlled decomposition mechanism. Water incursion rate was tested with different theoretical account discs of outer shell, which consisted of hydrogenated Castor oil and poly ethene ethanediol 6000. The survey consequences showed that the lag clip of the system could be controlled by altering the thickness and composing of the outer shell. On comparing the different disintegrants, carboxy methyl cellulose Ca was found to be the better disintegrant which can be used for the nucleus tablet. Assorted pulsatile release tablets with different slowdown times were designed for the drug isoniazide based on the cardinal surveies and the in vitro disintegration survey showed a typical pulsatile drug release.

Teruo Okano et al. , has discussed the different types of drug bringing systems using hydrogels which posses pulsatile drug bringing features. It has been observed that many critical maps of the human organic structure is regulated by the transient or pulsed release of bioactive substances so it is of import to present certain drugs a pulsed mode so as to mime the maps of the organic structure and minimise side effects. The present survey has chiefly focused on the thermally antiphonal poly ( N-isopropylacrylamide ) and its hydrogel derived functions. The article besides describes about the modified alginate gel beads development which has a characteristic pulsatile bringing.

Bin Li, JiaBi Zhu et al. , developed a pulsatile drug bringing system which delivers drug three times daily. The tablets in capsule system consisted of an impermeable capsule organic structure with two multi-layered tablets and a water-soluble cap. Hydroxy-propyl methyl cellulose and Na alginate was used as the modulating barrier stuff. The weight and the type of stuff of the modulating barrier significantly affected the slowdown clip. The slowdown clip was controlled between two pulsatile releases by seting the ratio of milk sugar and Na alginate. The ratio and slowdown clip showed a additive relationship. The survey besides demonstrated that by the add-on of a dividing bed between the 3rd and the modulating barrier bed, the release rate of the 2nd pulsatile dosage can be improved. It was besides found that the usage of milk sugar as bulking agent improved the drug release rate.

Bin Li, JiaBi Zhu et al. , developed a pulsatile drug bringing system which delivers drug three times daily. The tablets in capsule system consisted of an impermeable capsule organic structure with two multi-layered tablets and a water-soluble cap. Hydroxy-propyl methyl cellulose and Na alginate was used as the modulating barrier stuff. The weight and the type of stuff of the modulating barrier significantly affected the slowdown clip. The slowdown clip was controlled between two pulsatile releases by seting the ratio of milk sugar and Na alginate. The ratio and slowdown clip showed a additive relationship. The survey besides demonstrated that by the add-on of a dividing bed between the 3rd and the modulating barrier bed, the release rate of the 2nd pulsatile dosage can be improved. It was besides found that the usage of milk sugar as bulking agent improved the drug release rate.

Viral Shah et al. , developed a multiple unit based pulsatile bringing system for the intervention of asthma based on chronopharmaceutics utilizing the drug salbutamol sulfate which besides exhibits advantages like less side effects and first base on balls metamorphosis. The system consisted of an immediate release bed and a pulsatile release bed. The drug was loaded on to the non-pareil seeds utilizing PVP-K-30 ( 2 % ) as the binder in a conventional coating pan. It was coated with different concentrations of surfacing agent that is cellulose acetate phthalate and a changeless concentration of ethyl cellulose. The survey showed that the concentration of 4 % CAP and 2 % ethyl cellulose showed a successful pulsatile release.

Srikanth MV et al. , has discussed the different types and attacks involved in the development of pulsatile bringing system. Pulsatile bringing system has been classified into different type chiefly based on the mechanism involved. The different systems discussed are clip dependent systems, stimuli induced systems, external stimulation induced systems and pulsatile release systems for vaccinums and endocrines. In the clip controlled systems the drug release is controlled by the bringing system, in stimulation induced pulsatile system the release is controlled by different stimulations such as pH, enzymes present in the enteric piece of land or the bringing system and external stimulations like magnetic attraction, ultrasound, electrical consequence or irradiation.




Chemical name: 6-Chloro-3,4-dihydro-2H-1,2,4- benzothiadiazine-7-sulfonamide 1,1-dioxide

Molecular expression: C7H8ClN3O4S2

Molecular weight: 297.73

Description: white or about white, crystalline pulverization, odourless

Solubility: soluble in propanone ; meagerly soluble in ethyl alcohol ( 95 % ) ; really somewhat soluble in H2O. Dissolves in dilute solutions of alkali hydrated oxide.

Ultraviolet spectrum: 273nm

Class: Diuretic

Dose: 12.5 to 100mg

Dosage signifier: capsules, tablets, unwritten solution


Hydrochlorothiazide, belonging to the thiazide category of water pills, Acts of the Apostless by barricading the resorption of Na and chloride ions, and it thereby increasing the measure of Na tracking through the distal tubule of the uriniferous tubule and therefore increasing the volume of H2O excreted.


The three mechanisms proposed for the acute antihypertensive effects of thiazides are decrease in blood volume and cardiac end product, natriuretic consequence and a direct vasodilatory consequence. The plasma volume returns toward normal with its chronic disposal but peripheral vascular opposition is decreased.


Bioavailability: 65-75 %

Protein binding: 40-60 %

Metamorphosis: does non undergo important metamorphosis

( & gt ; 95 % excreted unchanged in piss )

Elimination: Chiefly excreted unchanged in urine

Half life: 6 to 10 hours / 2.5 A± 0.2 hour

Paths: Oral


Synonym: Cellacefate, Cellulose ethanoate phthalate, cellulose ethanoate H phthalate, Aquacoat cPD

Chemical name: Cellulose acetate 1,2-benzenedicarboxylate

Functional class: Coating agent

Description: White, free-flowing pulverization or colorless flakes ; odourless or with a weak smell of acetic acid ; hygroscopic.

Solubility: Freely soluble in propanone ; soluble in diethylene ethanediol and in dioxan ; practically indissoluble in H2O, in ethyl alcohol ( 95 % ) , in methylbenzene and in chlorinated and non-chlorinated aliphatic hydrocarbons. It dissolves in dilute solutions of base.

Melting point: 192aµ’C

Density ( majority ) : 0.260 g/cm3

Density ( tapped ) : 0.266 g/cm3

Use: used as an enteral movie surfacing stuff or as a matrix binder for tablets and capsules.


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Synomyms: Aquacoat ECD ; Aqualon ; Ashacel ; E462 ; Ethocel ; Ethylcellulosum ; Surelease.

Chemical name: Cellulose ethyl ether

Functional Class: Coating agent ; seasoning agent ; tablet binder ; tablet filler ; Viscosity increasing agent

Description: Ethyl cellulose is a tasteless, free-flowing, white to light sunburns colored pulverization.

Solubility: practically indissoluble in glycerol, propene ethanediol and H2O ; freely soluble in trichloromethane, methyl ethanoate and tetrahydrofuran, and in mixtures of aromatic hydrocarbons with ethyl alcohol ( 95 % ) .

Density ( majority ) : 0.4 g/cm3

Use: Hydrophobic surfacing agent for tablets and granules ; Ethyl cellulose coatings are used to modify the release of a drug, to dissemble an unpleasant gustatory sensation, or to better the stableness of a preparation


Synonym: Bleached wax ; cera alba

Chemical Name: White beeswax

Functional Class: Controlled-release agent ; stabilising agent ; stiffening agent.

Description: Yellow-white pieces or home bases, translucent when thin, with a all right grained, matt, non-crystalline break ; becomes soft and fictile when warmed by manus. Odour, swoon and characteristic.

Solubility: Partially soluble in hot ethyl alcohol ( 90 % ) and in quintessence ; practically indissoluble in H2O ; wholly soluble in volatile and fixed oils.

Melting scope: 60-67aµ’C

Density: 0.95-0.96 g/cm3

Use: Used to increase the consistence of picks and unctions, and to stabilise water-in-oil emulsions. White wax is used to smooth sugar coated tablets and to set the runing point of suppositories.


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Molecular Formula: C56H108O30

Molecular Weight: 3912.39

Description: White to whitish pulverization

Solubility: Swells in cold H2O, indissoluble in hot H2O, soluble in most organic dissolvers.

Melting point: 56.2aµ’C

Density: 1.39 g/cm3

Chemical belongingss: HPMC is cellulose ether, derived from base treated cellulose that is reacted with methyl chloride and propene.

Uses: Used as an enteral movie surfacing stuff or a matrix binder in solid dose signifiers. Used as a viscousness control agent, gelling agent, movie former, stabilizer, dispersant, lubricator, binder, emulsifying agent and suspending agent. End applications include adhesives and gums, agribusiness, edifice stuffs, personal attention merchandises, detergents and wetting agents, pigments, publishing inks and coatings, pharmaceuticals, nutrient merchandises, polymerisation and fabrics.


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