Biomedical subjects

G Bonacucina

Publications and source records attributed to G Bonacucina.

3 recordsLinked to original sources

PubMed2001

Spray-drying as a method for microparticulate controlled release systems preparation: advantages and limits. I. Water-soluble drugs.

Spray-drying was used for the preparation of paracetamol/eudragit RS or RL or ethylcellulose microspheres to verify the possibility of their use in controlled-release solid-dosage forms formulation and try to determine advantages and limits of the technique of such use. Microspheres were first characterized by scanning electron microscopy, differential scanning calorimetry, x-ray diffractometry, and in vitro dissolution studies and then used for the preparation of tablets. During this step, the compressibility of the spray-dried powders was also evaluated. In vitro dissolution studies were performed also on the tablets and their release control was accessed. Although powders were unable to slow down drug release, tablets obtained from microsphere compression showed a good capability of controlling paracetamol release when eudragit RS or ethylcellulose was used, even at low polymer amounts.

Acetaminophen↗

PubMedDate not supplied

Tabletted polylactide microspheres prepared by a w/o emulsion-spray drying method.

An emulsification-spray drying technique is used to prepare poly(D,L-lactic acid) (PDLLA) microparticles loaded with a water soluble, non-steroidal anti-inflammatory drug (NSAID), sodium naproxen (NaNPX). The method involves the preparation of a w/o emulsion in which the water soluble drug is dissolved in the aqueous dispersed phase, while the polymer is dissolved in the organic continuous phase. As a comparison, microparticles were prepared by spraying a suspension of the drug into an organic solution of the polymer. The spray-dried particles were characterized using SEM, DSC, XRD and in vitro release tests. The spray-dried product was then compressed (direct compression) to obtain controlled release matrix tablets. All microparticles release NaNPX within 30 min. The matrix tablets release the drug in 8-10 h; the matrix tablets characterized by the presence of surfactant (due to the emulsion used to obtain the microparticles) have the highest release rate.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMedDate not supplied

Gastro-resistant microspheres containing ketoprofen.

Ketoprofen gastroresistant microspheres were prepared by spray-drying using common pH dependent polymers, such as Eudragit S and L, CAP, CAT and HPMCP. The long ketoprofen recrystallization time was a serious hindrance to the preparation of microspheres having a drug content higher than 35%. Microspheres were characterized by scanning electron microscopy, differential scanning calorimetry, X-ray diffractometry and in vitro dissolution studies, and used for the preparation of tablets. During this step, the compaction ability of the spray-dried powders was measured. While the compressibility of the microspheres containing the enteric cellulosic derivatives are not acceptable and different from those of the microcrystalline cellulose, the compaction properties of ketoprofen/Eudragit L or S microspheres are comparable to those of the Avicel PH 101. In vitro dissolution studies were performed on the microspheres and the tablets. All microspheres showed a good gastroresistance, but some differences among the five polymers in reducing drug release at low pH values are present. Acrylic polymers (Eudragit L or S) are considerably more effective than the cellulosic derivatives CAP and CAT, while the HPMCP profile is in an intermediate position. These differences are erased by the microspheres compression process. In HCl 0.1 N, the percentage of ketoprofen released from the tablets is always close to zero, independently from the polymer used.

Acrylates↗