Search results for "Dosage form"

Microparticles derived from marine sponge collagen (SCMPs): preparation, characterization and suitability for dermal delivery of all-trans retinol.

2002

Abstract Collagen microparticles were prepared using marine sponge collagen. For this purpose a previous method by Rossler et al. (J. Microencapsul. 12 (1995) 49) of emulsification and cross-linking of native calf collagen was modified. The modified method for sponge collagen microparticles (SCMPs) achieved a yield of 10%. Scanning electromicroscopic photographs showed spherical particles with a diameter of 120–300 nm and photon correlation spectroscopic measurements indicated particle size range from 126 (±2.9) to 2179 (±342) nm. This broad size distribution was caused by some agglomerates that could not be destroyed by ultrasonication. The surface charge was measured as a function of pH. …

Mechanistic Understanding of Food Effects: Water Diffusivity in Gastrointestinal Tract Is an Important Parameter for the Prediction of Disintegration…

2013

Much interest has been expressed in this work on the role of water diffusivity in the release media as a new parameter for predicting drug release. NMR was used to measure water diffusivity in different media varying in their osmolality and viscosity. Water self-diffusion coefficients in sucrose, sodium chloride, and polymeric hydroxypropyl methylcellulose (HPMC) solutions were correlated with water uptake, disintegration, and drug release rates from trospium chloride immediate release tablets. The water diffusivity in sucrose solutions was significantly reduced compared to polymeric HPMC and molecular sodium chloride solutions. Water diffusivity was found to be a function of sucrose concen…

Different Dissolution Media Lead to Different Crystal Structures of Talinolol with Impact on Its Dissolution and Solubility

2003

During the performance of dissolution tests with immediate and controlled-release talinolol tablets it was detected that the type of the buffer used as dissolution medium had a strong influence on the solubility and the dissolution behavior of the drug. It was proven that talinolol appeared in different crystal structures with strongly differing solubilities when pure water, acetate, or phosphate buffers were employed as dissolution media. The resulting crystal structures were characterized by means of light microscopy, differential scanning calorimetry, and X-ray powder diffraction. All methods were adjuvant to detect changes in talinolol crystal structures. The different solubility and di…

A new biodegradable and biocompatible hydrogel with polyaminoacid structure

2007

The preparation and physicochemical and biological characterization of a novel polyaminoacid hydrogel have been reported. The ,-poly(N-2- hydroxyethyl)-dl-aspartamide (PHEA) has been used as a starting polymer for a derivatization reaction with methacrylic anhydride (MA) to give rise to the methacrylate derivative named PHM. Photocrosslinking of PHM has been performed in aqueous solution at 313 nm and in the absence of toxic initiators. PHM-based hydrogel has been characterized by scanning electron microscopy, X-ray diffractometry, swelling measurements in aqueous media; the degradation of PHM-based hydrogel has been evaluated as a function of time in the absence or in the presence of ester…

Nortriptyline for smoking cessation: Release and human skin diffusion from patches

2009

Abstract The objective of this work was to develop a simple and inexpensive transdermal formulation containing Nortriptyline Hydrochloride (NTH) for smoking cessation support therapy. Hydroxypropyl-methyl-cellulose was chosen as polymer and a mixture of transdermal enhancers (selected from previous research) was incorporated. The formulations were characterised in terms of appearance, thickness, uniformity of NTH content, release and skin permeation. Release studies demonstrated controlled release for four formulations. Diffusion studies were performed through human heat separated epidermis (HHSE) using Franz Diffusion Cells (FDC). Patches provided different fluxes varying from 20.39 ± 7.09…

A novel soft robotic pediatric in vitro swallowing device to gain insights into the swallowability of mini-tablets Authors

2022

Photocrosslinking of dextran and polyaspartamide derivatives: a combination suitable for colon-specific drug delivery.

2007

Abstract The aim of this study was to prepare and characterize novel hydrogels with polysaccharide–polyaminoacid structure, able to undergo an enzymatic hydrolysis in the colon and potentially useful for treating inflammatory bowel diseases (IBD). Starting materials were methacrylated dextran (DEX-MA) and methacrylated α,β-poly(N-2-hydroxyethyl)- dl -aspartamide (PHM). These polymers were photocrosslinked by exposure of their aqueous solutions at 313 nm without photoinitiators. Different samples, shaped as microparticles, were obtained as a function of polymer concentration and irradiation time. FT-IR analysis confirmed the occurrence of a co-crosslinking between DEX-MA and PHM in all exper…

Paediatric solid oral dosage forms for combination products: Improving in vitro swallowability of minitablets using binary mixtures with pellets

2023

There is a growing interest in determining and improving the acceptability of solid oral dosage forms (SODF) in paediatric populations. Combination products can be an interesting solution to combine two active pharmaceutical ingredients. This study shows that binary mixture of paediatric SODF could enhance formulation swallowability and palatability. Using the Paediatric Soft Robotic Tongue (PSRT) – an in vitro device inspired by the anatomy and physiology of 2-year-old children – we investigated the oral phase of swallowing of multi-particulate formulations, i.e., pellets (350 and 700 µm particles), minitablets (MTs, 1.8 mm), and their binary mixtures (BM), by measuring the oral swallowing…

Biodegradable microtablets made of low molecular weight polyglycolic acid: Bioabbaubare Mikrotabletten aus niedermolekularer Polyglycolsäure

1991

Research work in developing pharmaceutical dosage forms with biodegradable polymers seldom dealt with polyglycolic acid (PGA)1,2. This because of difficult processing procedures and low solubility of PGA in common organic solvents2,3. The only licensed product of the homoplymer in medical use is the sufgical suture Dexon®4

Viscosimetric investigation of the interaction between sodium dodecylsulfate micelles and a polymer drug carrier

1993

Abstract The viscosities of aqueous sodium dodecyl sulfate solutions with and without α,β-poly( N -hydroxyethyl)- dl -aspartamide (PHEA), at 15, 25 and 35°C are reported. The viscosities of SDS and of PHEA aqueous solutions are discussed in terms of the parameter D [D = ( η η 0 − 1)/φ] describing the non-ideal behavior of SDS micelles and of PHEA macromolecules. The viscosities of SDS plus PHEA aqueous solutions, discussed in terms of the parameter F [ F = η rel ( PHEA ) + η rel ( SDS ) − η rel ( SDS + PHEA )] M , demonstrate the occurrence of interactions between SDS micelles and the PHEA macromolecule. Both D and F are scarcely influenced by temperature variation.