Studies on applicability of press-coated tablets using hydroxypropylcellulose (HPC) in the outer shell for timed-release preparations

Fukui, Eiji; Uemura, Katsuji; Kobayashi, Masao

doi:10.1016/s0168-3659(00)00261-3

Cited by 64 publications

(23 citation statements)

References 9 publications

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“…In order to achieve the development of chronopharmaceutical dosage forms, currently, the siteand/or time-controlled release preparation with a designated initial lag time phase without drug release followed by a rapid release phase has been investigated. [5][6]14 These preparations enable us to predict and reproduce the drug absorption at the predetermined time and/or site. For this purpose, various designed dosage forms including the time clock system and sigmoidal release systems have been developed by using various unique techniques and functional polymers or additives.…”

Section: Resultsmentioning

confidence: 99%

“…[3][4] Time-controlled release preparations have been extensively developed to achieve time-and/or site-specific release. [5][6][7] In order to achieve the chronopharmaceutical design for these time-controlled release preparations, currently formulation design to control the lag time is prior to the substantial release of drug. [8][9] Recently, a TIMERx technology with an erosion mechanism was developed to achieve the chronotherapeutic delivery system.…”

Section: Introductionmentioning

confidence: 99%

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Hydrophilic excipients modulate the time lag of time-controlled disintegrating press-coated tablets

Lin

2004

AAPS PharmSciTech

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An oral press-coated tablet was developed by means of direct compression to achieve the time-controlled disintegrating or rupturing function with a distinct predetermined lag time. This press-coated tablet containing sodium diclofenac in the inner core was formulated with an outer shell by different weight ratios of hydrophobic polymer of micronized ethylcellulose (EC) powder and hydrophilic excipients such as spray-dried lactose (SDL) or hydroxypropyl methylcellulose (HPMC). The effect of the formulation of an outer shell comprising both hydrophobic polymer and hydrophilic excipients on the time lag of drug release was investigated. The release profile of the press-coated tablet exhibited a time period without drug release (time lag) followed by a rapid and complete release phase, in which the outer shell ruptured or broke into 2 halves. The lag phase was markedly dependent on the weight ratios of EC/SDL or EC/HPMC in the outer shell. Different time lags of the press-coated tablets from 1.0 to 16.3 hours could be modulated by changing the type and amount of the excipients. A semilogarithmic plot of the time lag of the tablet against the weight ratios of EC/SDL or EC/HPMC in the outer shell demonstrated a good linear relationship, with r = 0.976 and r = 0.982, respectively. The predetermined time lag prior to the drug release from a presscoated tablet prepared by using a micronized EC as a retarding coating shell can be adequately scheduled with the addition of hydrophilic excipients according to the time or site requirements.

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Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Hydrophilic excipients modulate the time lag of time-controlled disintegrating press-coated tablets

Lin

2004

AAPS PharmSciTech

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“…The initial drug release from this system is delayed by the coating of polymeric barriers until the polymeric shell is completely swollen or eroded. The delayed drug release is dependent on the characteristics of the shell, but not influenced by the core composition (Otsuka and Matsuda, 1995;Takenchi et al, 2000;Ishino et al, 1992;Fukui et al, 2000). The coated polymeric barriers may prevent penetration of dissolution media so there is a long lag time of the initial drug release.…”

Section: Current Issues and Challenges Of Multi-layered Tabletsmentioning

confidence: 99%

“…The coated polymeric barriers may prevent penetration of dissolution media so there is a long lag time of the initial drug release. However, once the media penetrates into the core, the core tablet will dissolve and/or swell to break the outer shell resulting in fast drug release (Fukui et al, 2000;Fukui et al, 2001;Lin et al, 2001). According to the dissolution profiles of core tablets and two types of press coated tablets, the press coated tablets showed the lag phase and the drug was released rapidly after the lag time (Fukui et al, 2000).…”

Section: Current Issues and Challenges Of Multi-layered Tabletsmentioning

confidence: 99%

Multi-Layered Matrix Tablets with Various Tablet Designs and Release Profiles

Choi¹,

Jeong²

2011

Journal of Pharmaceutical Investigation

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− Tablet dosage forms have been preferred over other formulations for the oral drug administration due to their low manufacturing costs and ease of administrations, especially controlled-release applications. Controlled-release tablets are oral dosage forms from which the active pharmaceutical ingredient (API) is released over an intended or extended period of time upon ingestion. This may allow a decrease in the dosing frequency and a reduction in peak plasma concentrations and hence improves patient compliance while reducing the risk of undesirable side effects. Conventional singlelayered matrix tablets have been extensively utilized to deliver APIs into the body. However, these conventional single-layered matrix tablets present suboptimal delivery properties, such as non-linear drug delivery profiles which may cause higher side effects. Recently, a multi-layered technology has been developed to overcome or eliminate the limitations of the singlelayered tablet with more flexibility. This technology can give a good opportunity in formulating new products and help pharmaceutical companies enhancing their life cycle management. In this review, a brief overview on the multi-layered tablets is given focusing on the various tablet designs, manufacturing issues and drug release profiles.

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“…These copolymers have been used, for instance, for modulated delivery of antithrombotic 16,18 and thrombolitic agents, 16 as a novel separation carrier in fluorescence immunoassays, 19 and in a glucose-sensitive polymeric composite membrane for modulated permeation of insulin. 20 Diltiazem hydrochloride (DIL.HCl), an antihypertensive drug that has been used recently as a model drug by several authors, 2,[27][28][29][30] was chosen as a model active pharmaceutical material because of its good solubility in water and buffered solutions. The main goal of this contribution was to elucidate the influence of the copolymer composition on the DIL.HCl delivery from cross-linked P[(N-iPAAm)-co-(MAA)] copolymer hydrogels.…”

Section: Introductionmentioning

confidence: 99%

The influence of the copolymer composition on the diltiazem hydrochloride release from a series of pH-sensitive poly[(N-isopropylacrylamide)-co-(methacrylic acid)] hydrogels

Díez-Peña

Frutos

et al. 2004

AAPS PharmSciTech

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A series of poly[(N-isopropylacrylamide)-co-(methacrylic acid)] (P[(N-iPAAm)-co-(MAA)]) hydrogels was investigated to determine the composition that exhibits a better pHmodulated release of diltiazem hydrochloride (DIL.HCl). For this purpose hydrogel slabs were loaded with DIL.HCl by the immersion method, and its release under acidic medium (0.1N HCl, pH 1.2) and in phosphate buffer pH 7.2, using United States Pharmacopeia (USP) 24 Apparatus 1, was investigated. According to the results from the slabs, copolymers with 85% mol N-iPAAm content were selected to prepare tablets with different particle size. The effect of pH and particle size changes on DIL.HCl release from these last hydrogel tablets was investigated by a stepwise pH variation of the dissolution medium. The amount of DIL.HCl released from high N-iPAAm content copolymer slabs under acidic pH medium was not only very low but it was also released at a slow rate. In the 85% N-iPAAm tablets, significant differences between and within release profiles were found as a function of particle size and pH, respectively. A relationship between particle size and release rate has been found. The lower DIL.HCl release at acidic pH from enriched N-iPAAm copolymers is interpreted by a cooperative thermal-and pHcollapse. Although for the whole range of copolymer composition a dependence of the equilibrium of swelling on the pH was found, DIL.HCl release experiments indicated that hydrogels with 85% mol N-iPAAm are the more adequate to be used for modulated drug delivery systems. Additionally, the particle size of the tablet can be used to tailor the release rate.

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Studies on applicability of press-coated tablets using hydroxypropylcellulose (HPC) in the outer shell for timed-release preparations

Cited by 64 publications

References 9 publications

Hydrophilic excipients modulate the time lag of time-controlled disintegrating press-coated tablets

Hydrophilic excipients modulate the time lag of time-controlled disintegrating press-coated tablets

Multi-Layered Matrix Tablets with Various Tablet Designs and Release Profiles

The influence of the copolymer composition on the diltiazem hydrochloride release from a series of pH-sensitive poly[(N-isopropylacrylamide)-co-(methacrylic acid)] hydrogels

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