Authors:F. Giordano, A. Rossi, R. Bettini, A. Savioli, A. Gazzaniga, and Cs. Novák
The thermal behavior of binary mixtures of paracetamol and a polymeric excipient (microcrystalline cellulose, hydroxypropylmethylcellulose
and cross-linked poly(vinylpyrrolidone)) was investigated. The physical mixtures, ranging from 50 to 90% by mass of drug,
were submitted to a heating-cooling-heating program in the 35–180C temperature range. Solid-state analysis was performed
by means of differential scanning calorimetry (DSC), hot stage microscopy (HSM), micro-Fourier transformed infrared spectroscopy
(MFTIR), and scanning electron microscopy (SEM).
The polymeric excipients were found to address in a reproducible manner the recrystallization of molten paracetamol within
the binary mixture into Form II or Form III. The degree of crystallinity of paracetamol in the binary mixtures, evaluated
from fusion enthalpies during the first and second heating scans, was influenced by the composition of the mixture, the nature
of the excipient and the thermal history. In particular, DSC on mixtures with cross-linked poly(vinylpyrrolidone) and hydroxypropylmethylcellulose
with drug contents below 65 and75%, respectively, evidenced the presence only of amorphous paracetamol after the cooling phase.
Microcrystalline cellulose was very effective in directing the recrystallization of molten paracetamol as Form II.
during the development of solid dosage forms, large scale development trials are normally preceded by the assessment of possible interactions between a drug and different excipients used in the formulation [ 2 , 3 ]. Although, excipients are required to
Authors:Bogdan Tiţa, Adriana Fuliaş, Zoltan Szabadai, Gerlinde Rusu, Geza Bandur, and Dumitru Tiţa
-degenerative diseases like Alzheimer’s disease could potentially be treated with Cox-2 inhibitors [ 5 ].
Studies of drug–excipient compatibility represent an important phase in the preformulation stage for the development of all dosage forms. In fact potential
Authors:Shravan Singh Thakur, Manik Pavan Kumar Maheswaram, Dhruthiman Reddy Mantheni, Lakshmi Kaza, Indika Perara, David W. Ball, John Moran, and Alan T. Riga
morphologies, as well as many others where the presence of a particular morphology could be detrimental to the formulation.
In previous studies, methods employed to determine the extent of crystallinity of APIs and excipients included the use of
Authors:Satya Girish Avula, Kenneth Alexander, and Alan Riga
preformulation tool in predicting the eutectic compositions of various drugs and excipients at their preliminary stages of formulation.
From the results, provided in the tables, it is clear that a good correlation
In the design of quality drug products, excipients and polymers play an important role. Excipients are the chemical substances which affect the functionality, stability and drug release behaviour. Excipients are
Authors:Nihar Ranjan Pani, Lila Kanta Nath, Sujata Acharya, and Biswanath Bhuniya
Chemical structure of nateglinide
The excipients are generally used in dosage form to ease in administration of drug, to facilitate the formulation of the drug product, to increase the stability of the formulation, for
Authors:Flávia Pires Maximiano, Kátia Monteiro Novack, Maria Terezinha Bahia, Lívia Lira de Sá-Barreto, and Marcílio Sérgio Soares da Cunha-Filho
pharmacokinetic properties, such as relatively short terminal half-life and limited tissue penetration [ 5 – 7 ]. Therefore, studies to determine its polymorphism and excipient compatibility are essential to design the proper pharmaceutical dosage forms of this
Authors:Marco Júnio Peres-Filho, Marilisa Pedroso Nogueira Gaeti, Stela Ramirez de Oliveira, Ricardo Neves Marreto, and Eliana Martins Lima
When developing tablet formulations, during early preformulation studies, it is relevant to evaluate physical and chemical interactions between an active pharmaceutical ingredient (API) and excipients [ 1 – 3
Authors:Z. Aigner, R. Heinrich, E. Sipos, G. Farkas, A. Ciurba, O. Berkesi, and P. Szabó-Révész
Compatibility of an active pharmaceutical ingredient (API) with excipients is one of the key factors influencing the stability of a formulation, because the excipients can interact with the active agent both