Preparation and In-vitro Characterization of Gastroretentive Floating Tablets of Domperidone

The present investigation was design for domperidone floating table preparation and in-vitro characterization. The ultimate target was increasing gastric retention by means of floatability of the tablet. Hydrophilic cellulosic polymers, Methocel K15M and Methocel K100M were used in this experiment for achieving release controlling property. Sodium bicarbonate played the key role of floatation by generating gas. Direct compression was the method of choice for preparing the tablets. The tablets were evaluated for physical parameters, buoyancy study, total floating time determination and dissolution study. Acidic dissolution medium (0.1N HCl), mimicking the environment of the stomach, was used in USP II apparatus for 12 hours to find out the pattern of drug release. The release mechanism was analyzed by exploring the zero order, first order, Higuchi and Korsmeyer equations. All the physical parameters were within acceptable range and Methocel K100M showed more floating lag time and sustained release property than Methocel K15M. All the formulations showed more than 12 hours floating time. Fourier Transform Infrared Spectroscopy (FTIR) study confirmed the compatibility of the drug with the excipients. Bangladesh Pharmaceutical Journal 22(2): 170-175, 2019

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Discovery of Novel Imidazopyridine GSK-3β Inhibitors Supported by Computational Approaches

Molecules ◽

10.3390/molecules25092163 ◽

2020 ◽

Vol 25 (9) ◽

pp. 2163

Author(s):

Rosa Buonfiglio ◽

Federica Prati ◽

Martina Bischetti ◽

Claudia Cavarischia ◽

Guido Furlotti ◽

...

Keyword(s):

Fine Tuning ◽

Inhibition Activity ◽

Design Synthesis ◽

In Vitro Characterization ◽

Gsk 3Β ◽

In Silico Models ◽

Acidic Hydrogen

The interest of research groups and pharmaceutical companies to discover novel GSK-3β inhibitors has increased over the years considering the involvement of this enzyme in many pathophysiological processes and diseases. Along this line, we recently reported on 1H-indazole-3-carboxamide (INDZ) derivatives 1–6, showing good GSK-3β inhibition activity. However, they suffered from generally poor central nervous system (CNS) permeability. Here, we describe the design, synthesis, and in vitro characterization of novel imidazo[1,5-a]pyridine-1-carboxamide (IMID 1) and imidazo[1,5-a]pyridine-3-carboxamide (IMID 2) compounds (7–18) to overcome such liability. In detail, structure-based approaches and fine-tuning of physicochemical properties guided the design of derivatives 7–18 resulting in ameliorated absorption, distribution, metabolism, and excretion (ADME) properties. A crystal structure of 16 in complex with GSK-3β enzyme (PDB entry 6Y9S) confirmed the in silico models. Despite the nanomolar inhibition activity, the new core compounds showed a reduction in potency with respect to INDZ derivatives 1–6. In this context, Molecular Dynamics (MD) and Quantum Mechanics (QM) based approaches along with NMR investigation helped to rationalize the observed structure activity relationship (SAR). With these findings, the key role of the acidic hydrogen of the central core for a tight interaction within the ATP pocket of the enzyme reflecting in good GSK-3β affinity was demonstrated.

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In Vitro Characterization of Peptidoglycan-Associated Lipoprotein (PAL)–Peptidoglycan and PAL–TolB Interactions

Journal of Bacteriology ◽

10.1128/jb.181.20.6306-6311.1999 ◽

1999 ◽

Vol 181 (20) ◽

pp. 6306-6311 ◽

Cited By ~ 67

Author(s):

Emmanuelle Bouveret ◽

Hélène Bénédetti ◽

Alain Rigal ◽

Erwann Loret ◽

Claude Lazdunski

Keyword(s):

Outer Membrane ◽

Cell Envelope ◽

Membrane Integrity ◽

Periplasmic Protein ◽

Multiprotein Complex ◽

In Vitro Characterization ◽

In Vitro Interaction

ABSTRACT The Tol-peptidoglycan-associated lipoprotein (PAL) system ofEscherichia coli is a multiprotein complex of the envelope involved in maintaining outer membrane integrity. PAL and the periplasmic protein TolB, two components of this complex, are interacting with each other, and they have also been reported to interact with OmpA and the major lipoprotein, two proteins interacting with the peptidoglycan. All these interactions suggest a role of the Tol-PAL system in anchoring the outer membrane to the peptidoglycan. Therefore, we were interested in better understanding the interaction between PAL and the peptidoglycan. We designed an in vitro interaction assay based on the property of purified peptidoglycan to be pelleted by ultracentrifugation. Using this assay, we showed that a purified PAL protein interacted in vitro with pure peptidoglycan. A peptide competition experiment further demonstrated that the region from residues 89 to 130 of PAL was sufficient to bind the peptidoglycan. Moreover, the fact that this same region of PAL was also binding to TolB suggested that these two interactions were exclusive. Indeed, the TolB-PAL complex appeared not to be associated with the peptidoglycan. This led us to the conclusion that PAL may exist in two forms in the cell envelope, one bound to TolB and the other bound to the peptidoglycan.

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Characterization of Autonomic Receptors in Isolated Human Parotid Acinar Cells

Journal of Dental Research ◽

10.1177/00220345800590021701 ◽

1980 ◽

Vol 59 (2) ◽

pp. 168-175 ◽

Cited By ~ 11

Author(s):

John A. Mangos

Keyword(s):

Adrenergic Receptors ◽

Acinar Cells ◽

Cellular Systems ◽

Parotid Acinar Cells ◽

In Vitro Characterization ◽

Muscarinic Cholinergic ◽

Autonomic Receptors

Isolated human parotid acinar cells have been used for the in vitro characterization of the muscarinic cholinergic and alpha- and beta-adrenergic receptors of these cells. The agonist-antagonist interactions at the receptor level were studied, and the role of the receptor-activated cellular systems in the process of secretion was characterized.

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Development of Glyceryl Monostearate Based Ciprofloxacin Hydrochloride Sustained Release Matrix Tablet: an In vitro Study

Dhaka University Journal of Pharmaceutical Sciences ◽

10.3329/dujps.v8i1.5340 ◽

1970 ◽

Vol 8 (1) ◽

pp. 81-88

Author(s):

Susmita Laila ◽

Tasnuva Haque ◽

Md Mesbah Uddin Taluker ◽

Ishtiaq Ahmed ◽

Muhammad Rashedul Islam ◽

...

Keyword(s):

Sustained Release ◽

Release Mechanism ◽

Physical Parameters ◽

Matrix Tablet ◽

Glyceryl Monostearate ◽

Ciprofloxacin Hydrochloride ◽

First Order ◽

Release Pattern ◽

First Order Kinetics

In this present study an attempt has been made to evaluate glyceryl monostearate (GMS) as a rateretarding material to sustain the release ciprofloxacin hydrochloride from the matrix tablet. The solubility ofciprofloxacin hydrochloride was studied. The physical parameters of the prepared tablets were also evaluated.Release kinetics of ciprofloxacin hydrochloride from this sustained release matrix was studied in 0.1 N HCl usingUnited States Pharmacopoeia type-II dissolution apparatus (paddle method). The effect of polymer load, drug load,hydroxylpropylmethylcellulose to compensate glyceryl monostearate (GMS) and different release modifiers wereexamined. It was observed that the release rate of drug was retarded with the increasing concentration of GMS. Therelease data were treated in different fashion to identify the release mechanism and it was revealed with fewexception that, when GMS is used as single polymer, release of active drug from the prepared matrix tablet appearedto follow the first order kinetics and showed the tendency to follow Korsmeyer model when HPMC 15 cps was usedalong with GMS. Using release enhancers the release pattern were fitted to first order kinetics. From the f2 values itcan be concluded that the release pattern of P-2, D-1, H-2 and H-3 are similar to P-1, whereas the formula of P-1, D-2and H-1 were same. MDT values were found to be increased with the increasing amount of polymer (GMS).Key words: Glyceryl monostearate; ciprofloxacin HCl; sustained release matrix; dissolution studies.DOI: 10.3329/dujps.v8i1.5340Dhaka Univ. J. Pharm. Sci. 8(1): 81-88, 2009 (June)

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