Understanding Poor Milling Behavior of Voriconazole from Crystal Structure and Intermolecular Interactions.

The study investigated the milling behavior of voriconazole (VRZ) subjected to particle size reduction using air jet mill at differential air pressures of 5, 6, 7, and 8 bar for five cycles at each pressure. The crystal structure of VRZ was probed for understanding the fracture behavior from crystal packing and intermolecular interactions using molecular modeling tools of attachment energy (), density functional theory, and energy framework analysis. Upon milling for different cycles, VRZ showed that size reduction from () 20 to 9 μm and 100% particles could not be milled to sizes below 9 μm, with the increase in either the milling intensity or cycle.

The Role of Cocrystallization-Mediated Altered Crystallographic Properties on the Tabletability of Rivaroxaban and Malonic Acid.

The present work aims to understand the crystallographic basis of the mechanical behavior of rivaroxaban-malonic acid cocrystal (RIV-MAL Co) in comparison to its parent constituents, i.e., rivaroxaban (RIV) and malonic acid (MAL).

Elucidating Molecular- and Particle-Level Changes during the Annealing of a Micronized Crystalline Drug.

Micronization of crystalline active pharmaceutical ingredients can lead to formation of a thermodynamically unstable material with surface disorder. This material undergoes structural stabilization and particle-level changes over time that, in turn, alters the surface properties and interparticle interactions of the micronized drug. The unstable nature of the micronized drug can lead to variability in the performance of dry powder inhaler drug products.

Correlations between surface composition and aerosolization of jet-milled dry powder inhaler formulations with pharmaceutical lubricants.

Co-jet-milling drugs and lubricants may enable simultaneous particle size reduction and surface coating to achieve satisfactory aerosolization performance. This study aims to establish the relationship between surface lubricant coverage and aerosolization behavior of a model drug (ciprofloxacin HCl) co-jet-milled with lubricants [magnesium stearate (MgSt) or l-leucine]. The co-jet-milled formulations were characterized for particle size, morphology, cohesion, Carr's index, and aerosolization performance.

Continuous Twin Screw Wet Granulation and Drying-Control Strategy for Drug Product Manufacturing.

The use of continuous manufacturing has been increasing within the pharmaceutical industry over the last few years. Continuous direct compression has been the focus of publications on the topic to date. The use of wet granulation can improve segregation resistance, uniformity, enhance density, and flow properties for improved tabletability, or improve stability of products that cannot be manufactured by using a direction compression process.

Demonstration of pharmaceutical tablet coating process by injection molding technology.

We demonstrate the coating of tablets using an injection molding (IM) process that has advantage of being solvent free and can provide precision coat features. The selected core tablets comprising 10% w/w griseofulvin were prepared by an integrated hot melt extrusion-injection molding (HME-IM) process. Coating trials were conducted on a vertical injection mold machine.

Tablet coating by injection molding technology - Optimization of coating formulation attributes and coating process parameters.

We developed and evaluated a solvent-free injection molding (IM) coating technology that could be suitable for continuous manufacturing via incorporation with IM tableting. Coating formulations (coating polymers and plasticizers) were prepared using hot-melt extrusion and screened via stress-strain analysis employing a universal testing machine. Selected coating formulations were studied for their melt flow characteristics.

Integrated hot-melt extrusion - injection molding continuous tablet manufacturing platform: Effects of critical process parameters and formulation attributes on product robustness and dimensional stability.

This study provides a framework for robust tablet development using an integrated hot-melt extrusion-injection molding (IM) continuous manufacturing platform. Griseofulvin, maltodextrin, xylitol and lactose were employed as drug, carrier, plasticizer and reinforcing agent respectively. A pre-blended drug-excipient mixture was fed from a loss-in-weight feeder to a twin-screw extruder.

Development of Maltodextrin-Based Immediate-Release Tablets Using an Integrated Twin-Screw Hot-Melt Extrusion and Injection-Molding Continuous Manufacturing Process.

The combination of hot-melt extrusion and injection molding (HME-IM) is a promising process technology for continuous manufacturing of tablets. However, there has been limited research on its application to formulate crystalline drug-containing immediate-release tablets. Furthermore, studies that have applied the HME-IM process to molded tablets have used a noncontinuous 2-step approach.

Effect of different "states" of sorbed water on amorphous celecoxib.

Glass transition temperature (Tg) of an amorphous drug is a vital physical phenomenon that influences its visco-elastic properties, physical, and chemical stability. Water acts as a plasticizer for amorphous drugs thus increasing their recrystallization kinetics. This reduces the solubility advantage of an amorphous drug.

Solubility advantage from amorphous etoricoxib solid dispersions.

Objective: This study aimed to evaluate kinetic solubility advantage of amorphous etoricoxib solid dispersions prepared with three water soluble polymers and correlate it with solid state and supersaturated drug solution stabilization potential of these polymers.

Methods: Amorphous solid dispersions (ASDs) of etoricoxib were prepared with polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP) and hydroxyethyl cellulose (HEC) at 70:30w/w ratio and characterized for glass transition temperature (Tg), miscibility and intermolecular interactions. Kinetic solubility profiles of amorphous etoricoxib and its ASDs were determined in water at 37 °C.

Barrier coated drug layered particles for enhanced performance of amorphous solid dispersion dosage form.

Amorphous solid dispersions (ASDs) may entail tailor-made dosage form design to exploit their solubility advantage. Surface phenomena dominated the performance of amorphous celecoxib solid dispersion (ACSD) comprising of amorphous celecoxib (A-CLB), polyvinylpyrrolidone, and meglumine (7:2:1, w/w). ACSD cohesive interfacial interactions hindered its capsule dosage form dissolution (Puri V, Dhantuluri AK, Bansal AK 2011.

Effect of counterions on the properties of amorphous atorvastatin salts.

Amorphous systems have gained importance as a tool for addressing delivery challenges of poorly water soluble drugs. A careful assessment of thermodynamic and kinetic behavior of amorphous form is necessary for successful use of amorphous form in drug delivery. The present study was undertaken to evaluate effect of monovalent sodium (Na(+); ATV Na), and bivalent calcium (Ca(2+); ATV Ca) and magnesium (Mg(2+); ATV Mg) counterions on properties of amorphous salts of atorvastatin (ATV) model drug.

Role of α-relaxation on crystallization of amorphous celecoxib above T(g) probed by dielectric spectroscopy.

In the present study, the role of α-relaxation toward isothermal crystallization of amorphous celecoxib was studied using dielectric spectroscopy (DES). The dielectric response of the α-relaxation was measured as a function of frequency (10⁻¹ to 10⁶ Hz), isothermally at every 4 K interval in the range of 303.15 to 443.

Investigation of atypical dissolution behavior of an encapsulated amorphous solid dispersion.

Poor dissolution performance is one of the challenges encountered in dosage form design of amorphous solid dispersions (ASDs). This study was aimed to investigate the effect of solid-liquid interactions of an encapsulated ASD on drug release. Drug release profiles of a molecularly interacting amorphous celecoxib solid dispersion (ACSD) comprising of amorphous celecoxib (A-CLB), polyvinylpyrrolidone (PVP), and meglumine (7:2:1, w/w) were compared with crystalline CLB (C-CLB), in powder and capsule form.

Solid state characterization of commercial crystalline and amorphous atorvastatin calcium samples.

Atorvastatin calcium (ATC), an anti-lipid BCS class II drug, is marketed in crystalline and amorphous solid forms. The objective of this study was to perform solid state characterization of commercial crystalline and amorphous ATC drug samples available in the Indian market. Six samples each of crystalline and amorphous ATC were characterized using X-ray powder diffractometry (XRPD), differential scanning calorimetry (DSC), thermogravimetric analysis, Karl Fisher titrimetry, microscopy (hot stage microscopy, scanning electron microscopy), contact angle, and intrinsic dissolution rate (IDR).

Wettability and surface chemistry of crystalline and amorphous forms of a poorly water soluble drug.

The present study compares energetics of wetting behavior of crystalline and amorphous forms of a poorly water soluble drug, celecoxib (CLB) and attempts to correlate it to their surface molecular environment. Wettability and surface free energy were determined using sessile drop contact angle technique and water vapor sorption energetics was measured by adsorption calorimetry. The surface chemistry was elucidated by X-ray photoelectron spectroscopy (XPS) and crystallographic evaluation.

Coprocessing of nevirapine and stavudine by spray drying.

The objective of the present study was to coprocess 2 active pharmaceutical ingredients (APIs), nevirapine (NVP) and stavudine (STV), by spray drying technique to overcome the respective problems of poor solubility and poor content uniformity. The coprocessed product (NVP-STV CP) and untreated APIs were characterized by powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), particle size, surface area analysis, compressibility, and solubility. Coprocessing enhanced NVP solubility by approximately 1.