Bodhisattwa Chaudhuri

Bodhisattwa Chaudhuri
University of Connecticut | UConn · Department of Pharmaceutical Sciences, Chemical and Biomolecular Engineering Institute of Materials Science

Doctor of Philosophy

About

91
Publications
13,244
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1,316
Citations

Publications

Publications (91)
Article
Full-text available
A continuous manufacturing technology based on coaxial turbulent jet in coflow was previously developed to produce paclitaxel-loaded polymeric micelles. Herein, coarse-grained molecular dynamics (CG-MD) simulations were implemented to better understand the effect of the material attributes (i.e., the drug-polymer ratio and the ethanol concentration...
Article
Drying of wet granules in a fluidized bed dryer is an important part of the pharmaceutical tablet manufacturing process. Complicated gas-solid flow patterns appear in the fluidized bed dryer, and interphase momentum, heat, and mass transfer happen during the drying process. A coupled computational fluid dynamics (CFD)-discrete element method (DEM)-...
Article
Full-text available
The fluidized bed is an essential and standard equipment in the field of process development. It has a wide application in various areas and has been extensively studied. This review paper aims to discuss computational modeling of a fluidized bed with a focus on pharmaceutical applications. Eulerian, Lagrangian, and combined Eulerian-Lagrangian mod...
Article
Pharmaceutical applications of the 3D printing process have recently matured, followed by the FDA approval of Spritam, the first commercial 3D printed dosage form. Due to being a new technology in the conventional dosage formulation field, there is still a dearth of understanding in the 3D printing process regarding the effect of the raw materials...
Article
This paper reports a custom-built binder jet 3D printer for pilot-scale manufacturing of pharmaceutical tablets. The printer is equipped with high-throughput piezoelectric inkjet print heads and allows direct control of several key process parameters, including the build layer thickness, amount of jetted liquid binder, and powder spreading rate. Th...
Article
Full-text available
Large volumes of protein solutions are commonly stored in a frozen state before further drug product fill and finish. This study aimed to establish a design space to perform large-scale freeze-thaw (F/T) processes of biotherapeutics without inducing protein destabilization. A response surface model was designed to evaluate the following main factor...
Article
The current study utilized an artificial neural network (ANN) to generate computational models to achieve process optimization for a previously developed continuous liposome manufacturing system. The liposome formation was based on a continuous manufacturing system with a co-axial turbulent jet in a co-flow technology. The ethanol phase with lipids...
Preprint
In this study, a pre-screening test has been developed for the binder-jet 3D printing process (BJ3DP) which has been validated using statistical analysis. The pre-screening test or drop test has been adapted from the wet granulation field and modified later on to be used for tablet manufacturing in BJ3DP. Initially, a total of eight powders and ten...
Article
Triboelectric charging is defined as the phenomenon of charge transfer between two different material surfaces when they are brought into contact and separated. The focus of this research is the development of a Discrete Element Method (DEM) based simulation model to predict tribocharging during hopper discharge. Due to decreased particle-wall inte...
Article
Full-text available
Freezing is a common process applied in the pharmaceutical industry to store and transport biotherapeutics. Herewith, multi-scale molecular dynamics simulations of Lactate dehydrogenase (LDH) protein in phosphate buffer with/without ice formation performed to uncover the still poorly understood mechanisms and molecular details of protein destabiliz...
Article
Full-text available
3D printing is emerging as one of the most promising methods to manufacture Pharmaceutical dosage forms as it offers multiple advantages such as personalization of dosage forms, polypill, fabrication of complex dosage forms etc. 3D printing came into existence in 1980s but its use was extended recently to pharmaceutical industry along with the appr...
Article
Emerging 3D printing technologies offer an exciting opportunity to create customized 3D objects additively from a digital design file. 3D printing may be further leveraged for personalized medicine, clinical trial, and controlled release applications. A wide variety of 3D printing methods exists, and many studies focus on extrusion-based 3D printin...
Article
The drug loading efficiency was evaluated using a binder-jet 3D printing process by incorporating an active pharmaceutical ingredient (API) in ink, and quantifying the printability property of ink solutions. A dimensionless parameter Ohnesorge was calculated to understand the printability property of the ink solutions. A pre-formulation study was a...
Article
Storage of protein therapeutics in a frozen state provides operational flexibility for fill and finish of drug products and extends the shelf life of protein solutions. However, freezing of bulk protein solutions leads to progressive freeze-concentration of solutes which may result in protein instability. A novel method was designed to study the fr...
Article
Full-text available
The present study focuses on the implementation of a modified simplex centroid statistical design to predict the triboelectrification phenomenon in pharmaceutical mixtures. Two drugs (Ibuprofen and Theophylline), two excipients (Lactose Monohydrate and Microcrystalline Cellulose/MCC), and two blender wall materials (Aluminum and Poly-methyl Methacr...
Poster
v Purpose Results Objectives Methods • Mixing is one of the crucial unit operations widely used in pharmaceutical manufacturing to produce a homogenized mixture for both a tablet press and capsule filling machine. Parameters Coefficient of restitution (particle/wall) 0.2 Coefficient of restitution (particle/particle) 0.2 Frictional coefficient (par...
Article
Full-text available
Bulk solutions of therapeutic proteins are often frozen for long-term storage. During the freezing process, proteins in liquid solution redistribute and segregate in the interstitial space between ice crystals. This is due to solute exclusion from ice crystals, higher viscosity of the concentrated solution, and space confinement between crystals. S...
Article
Full-text available
FDA-approved self-emulsifying medicines rely on liquid-based formulations, which can exhibit limited stability and short shelf-lives. Solid self-emulsifying drug delivery systems (SEDDS) can improve such issues, but there is still a great need for identifying suitable porous carriers to convert liquid SEDDS into solids without impairing their mecha...
Article
Moisture-induced flow variabilities in pharmaceutical blends lead to multiple impediments during manufacturing of solid dosage formulations. Processing and storage humidity conditions both govern the moisture contents of the pharmaceutical mixtures and bear significant impact on the final product quality. In this study, experimentally validated Dis...
Article
Full-text available
High shear wet granulation (HSWG) is one of the most poorly understood processes with known difficulties in optimization and scale up. The purpose of the current study is to develop a DEM model which can be applied under dynamic process conditions with high predictive capacity to improve process insight. The DEM model is used to predict agglomerati...
Poster
The extensive applications of solid dosage formulations in the pharmaceutical industry necessitate the optimization of the powder flow properties and the development of reliable process modeling techniques to reduce various complications those may arise during powder handling. Relative humidity (%RH) plays a crucial role in powder flow behavior, a...
Article
Pharmaceutical powder flow can alter significantly based on the exposed humidity conditions, and lack of computational models to predict the same may undermine process development, optimization, and scale-up performances. A Discrete Element Model (DEM) is proposed to predict the effects of humidity on pharmaceutical powder flow by altering the cohe...
Article
The use of Pressurized metered dose inhalers (pMDIs) for the treatment of asthma and other chronic obstructive pulmonary diseases is frequently associated with breath–actuation synchronization problems and poor pulmonary delivery, particularly amongst the pediatric and geriatric population groups. Spacers, or Valved Holding Chambers (VHCs), are fre...
Article
Pulmonary delivery of cohesive and micronized drugs through Dry Powder Inhalers (DPIs) is traditionally achieved through the formation of ordered mixtures. In order to improve the mechanistic understanding of formation of ordered mixtures, the system consisting of micronized lactose (AZFL, representative of an active pharmaceutical ingredient) and...
Article
Process understanding for designing, optimizing and scaling of pharmaceutical unit operations is fundamentally important to address concerns of high risks, monumental costs, and productivity decline in the pharmaceutical industry. This is especially important in the rapidly changing landscape of the pharmaceutical industry. Pharmaceutical processes...
Article
The purpose of the present study was to develop guidance toward rational choice of blenders and processing conditions to make robust and high performing adhesive mixtures for dry-powder inhalers and to develop quantitative experimental approaches for optimizing the process. Mixing behavior of carrier (LH100) and AstraZeneca fine lactose in high-she...
Article
The continuous relative motion of particles against solid surfaces in pharmaceutical manufacturing triggers multiple physio-chemical alterations generating contact charging or triboelectrification. Charged particles in manufacturing processes can actuate multiple impediments including agglomeration, segregation during flow or adhesion to process eq...
Article
Full-text available
Particle sizes play a major role to mediate charge transfer, both between identical and different material surfaces. The study probes in to the probable mechanism that actuates opposite polarities between two different size fractions of the same material by analyzing the charge transfer patterns of two different sizes of MCC. Quantum scale calculat...
Chapter
Solid dose manufacturing is a critical step in procuring safe medications as it comprises sequence of complicated operations before the drug product is marketed. This chapter focuses on three unit operations: contact drying, film coating, and milling. It elucidates and addresses the effect of process variables and materials properties using experim...
Article
Most pharmaceutical powders are dielectric materials that often accumulate charge during manufacturing process. In this study, triboelectrification of binary mixtures of drug and excipient has been investigated. Powder samples for charge measurement were mixed using a V-blender and dispensed directly into a Faraday cup. The mixtures at intermediate...
Article
Pharmaceutical powders are very prone to electrostatic charging by colliding and sliding contacts. In pharmaceutical formulation processes, particle charging is often a nuisance and can cause problems in the manufacture of products, such as affecting powder flow, fill, and dose uniformity. For a fundamental understanding of the powder triboelectrif...
Conference Paper
Tribocharging attributes to the mechanism of static electrification between two dissimilar material surfaces when brought into contact and separated, triggering multiple impediments like segregation, agglomeration, material loss and severe explosions. Bipolar charging is a special case of triboelectrification observed between the surfaces of the sa...
Article
Particle size reduction by mechanical means is an important unit operation in the pharmaceutical industry, used to improve flow, solubility, and in amorphization of drugs. It is usually achieved by the fracturing of particles under the action of applied energy. Despite being pervasive in the pharmaceutical field, it is one of the least understood p...
Article
Electrostatic charging via contact electrification or tribocharging refers to the process of charge transfer between two solid surfaces when they are brought into contact with each other and separated. Charging of continuous particulate flows on solid surfaces is poorly understood and has often been empirical. This study aims towards understanding...
Article
Particle size reduction of dry granular material by mechanical means, also known as milling or comminution, is undoubtedly a very important unit operation in pharmaceutical, agricultural, food, mineral and paper industries. As comminution is a stochastic and a nonlinear process, an attempt was made to understand this complicated process by conducti...
Conference Paper
Electrostatic charging via contact electrification or tribocharging refers to the process of charging of two solid surfaces when they are brought into contact and separated. Pharmaceutical powders are quite prone to electrostatic charging by colliding and sliding contacts with walls and other particles. In formulation processes, particle charging i...
Conference Paper
Abstracts: * Understanding of pMDI-spacer interactions through CFD simulations.doc (30.0KB) - Uploading Abstracts
Conference Paper
Adhesive mixtures, in which fine powders (API) are attached to a coarse carrier are commonly used for DPI formulations. The formation and segregation of these adhesive mixtures depends on the balance of strength of cohesive and adhesive forces between the particles. The purpose of the current study is to improve the understanding of mixing and hand...
Conference Paper
Electrostatic charging via contact electrification or tribocharging refers to the process of charging of two solid surfaces when they are brought into contact and separated. In pharmaceutical formulation processes, particle charging is often a nuisance and can cause problems in the manufacture of products, such as powder flow, and fill level and do...
Conference Paper
The purpose of the current study is to develop a numerical model which can characterize flow and the resulting particle metrics (surface deposition, PSD etc.) when a commercial suspension based pMDI is sprayed into a spacer. The effect of different variables like volumetric rate of coaxially flowing air, spacer geometry and delay are investigated i...
Conference Paper
In pharmaceutical formulation processes, particle charging is often a nuisance and can cause problems in the manufacture of products, such as affecting powder flow, and reducing fill and dose uniformity. For a fundamental understanding of the powder triboelectrification, it is essential to study charge transfer under well-defined conditions. Hence...
Conference Paper
In pharmaceutical formulation processes, particle charging is often a nuisance and can cause problems in the manufacture of products, such as affecting powder flow, and reducing fill and dose uniformity. For a fundamental understanding of the powder triboelectrification, it is essential to study charge transfer under well-defined conditions. Hence...
Article
A systematic experimental investigation of contact drying operation was carried out in an agitated Charles Thompson filter-dryer. In this study, the effect of process parameters (wall temperature, impeller speed, fill level) on the drying performance in the filter-dryer is quantified as a function of bed temperature and solvent concentration. In ad...
Article
Full-text available
This purpose of this study is to investigate the role of physiochemical properties and operational conditions in determining the electrostatic interactions between two species on a surface under typical industrial conditions. The variables considered for the study were particle type, particle size and shape, loading mass, surface type, angle of inc...
Article
Particle size reduction of dry granular material by mechanical means, also known as milling or comminution, is undoubtedly a very important unit operation in pharmaceutical, agricultural, food, mineral and paper industries. Particle size reduction rate was studied by conducting parametric studies experimentally and computationally using Discrete El...
Article
The paper presents the results of an investigation of the role of different operational and material variables in the triboelectrification process and subsequent charge remediation by addition of different additives under typical production conditions encountered in the industry (35 ± 5% RH, 25 ± 2 °C). Different particle types, surfaces, additives...
Conference Paper
High shear wet granulation is traditionally defined as a unit operation which produces bigger granules from fine powder under the influence of a binder. The bigger granules have better flow and compressibility ensuring better mixing and content uniformity while retaining the same effective surface area for dissolution and minimizing solvent resista...
Article
Granular mixing is a critical but poorly understood aspect in the manufacture of many industrial products, for example, pharmaceuticals, food, cosmetics, ceramics, fertilizer and polymers. The mixing and segregation phenomenon occur in most systems of granular solids and have a significant influence on the quality and outcome of the final product....
Article
Drying is one of the most complex unit operations with simultaneous heat and mass transfer. The contact drying process is also not well understood as several physical phenomena occur concurrently. This paper reviews current experimental and modeling approaches employed towards a better understanding of the contact drying operation. Additionally, an...
Article
This review provides a comprehensive record of experimental and modeling approaches that can be used to study the effect of critical process parameters affecting the coating uniformity in pharmaceutical coating operation. Explicit reference is given to the development of the approach and its previous usage with particular emphasis on the advantages...
Article
Drying is one of the most commonly used unit operations in the preparation of dry granules by thermally removing volatile solvent from the wet solid. The study focuses on the quantitative investigation of heat transfer in a filter dryer in the quest to determine the optimum drying conditions. Consequently, contact drying kinetics of glassbeads–etha...
Conference Paper
Pharmaceutical manufacturing processes often consist of a series of unit operations, each intended to alter certain properties of the materials being processed leading to the embodiment of certain desired properties of the final product. To ensure acceptable variations, significant importance should be given to the mechanistic and parametric attrib...
Conference Paper
Full-text available
Particle size reduction of dry material by milling is a key unit operation for the pharmaceutical, agricultural, food and paper industries. Knowledge of particle flow and size reduction in a hammer mill is thus critical to optimize the design and operation of such equipment. Milling experiments are performed using lactose non pareils in a laborator...
Article
The purpose of this work is to investigate the effect of the coating process parameters on coating performance and coating variability, and hence determine the optimal operating conditions. Coating of particles is done to mask the unpleasant taste or odor of the drug, to control the bioavailability of the API, and to increase shelf-life. The coatin...
Article
The knowledge of the particle flow and mixing in a pan coater is critical to optimize the design and operation of coating equipment. Mixing is an important but poorly understood aspect of coating of pharmaceutical dosage forms (tablets). Our study focuses on the fundamental mechanisms of granular flow and mixing and their relationship to the coatin...
Article
Mixing is an important but poorly understood aspect in petrochemical, food, ceramics, fertilizer and pharmaceutical processing and manufacturing. Segregation and mixing phenomenon occur in most systems of powdered or granular solids and have a significant influence on their behavior. Deliberate mixing of granular solids is an essential operation in...
Article
This communication empirically correlates flow in two systems; an instrumented rotating drum (GDR) and a set of bench scale hoppers. A flow index obtained from measurements in the GDR is directly correlated to the flow through hoppers, providing a predictive method for hopper design and a convenient experimental test for screening materials and det...
Article
This communication empirically correlates flow in two systems; an instrumented rotating drum (GDR) and a set of bench scale hoppers. A flow index obtained from measurements in the GDR is directly correlated to the flow through hoppers, providing a predictive method for hopper design and a convenient experimental test for screening materials and det...
Article
Heat transport through flowing particulate materials is an essential component of modern technologies such as heterogeneous catalytic reactors, high performance cryogenic insulation, construction material, and powder metallurgy. In catalyst manufacturing, heat transfer through granular media occurs in the drying and calcination stages. In this pape...
Conference Paper
Coating of particles (tablets) is done to mask the unpleasant taste or odor of the drug, to control the bioavailability of the API, and to increase shelf-life. The coating solution is sprayed in specific locations of the granular bed and uniformity of coating is achieved by interparticle collisions and overall mixing behavior in the coater. Thus, t...
Article
Mixing is an important but poorly understood aspect in petrochemical, food, ceramics, fertilizer and pharmaceutical processing and manufacturing. Deliberate mixing of granular solids is an essential operation in the production of industrial powder products usually constituted from different ingredients. The knowledge of particle flow and mixing in...
Article
The focus of this study was the determination of mixing patterns and rates inside a cylindrical coating pan. The research for this study was divided into two parts. The first part examined the mixing pattern and the movement of tablets inside of a coating pan experimentally. The second part consisted of using a DEM (Discrete Element Model) simulati...
Article
In this paper we focus on the effect of cohesion and compression speed on the outcome of the compression process for both monodisperse and polydisperse granular systems. A three dimensional discrete element model (DEM) which incorporates static and dynamic friction is used in this study to simulate die filling, and the compaction and decompaction o...
Conference Paper
Coating of particles is done in the pharmaceutical industry, to mask the unpleasant taste or odor of the drug, to control the bioavailability of the drug, to protect the tablet from the environment (increase shelf-life), and sometimes to improve tablet appearance. During coating, the coating solution is sprayed at discrete locations on the cascadin...
Conference Paper
Coating of particles (tablets) is done to mask the unpleasant taste or odor of the drug, to control the bioavailability of the API, and to increase shelf-life. The coating solution is sprayed in specific locations of the granular bed and uniformity of coating is achieved by interparticle collisions and overall mixing behavior. Thus, the knowledge o...
Article
Dynamic (flow — induced) expansion (dilation) of fine powders inside a rotating drum is investigated. Most previous work on powder dilation is based on two-phase effects, where the presence of air either drives the flow (fluidized bed), or air needs to be displaced for the powder to flow (hoppers). Experimental results show that for many common pow...
Article
This paper describes a new method to quantitatively measure the flow characteristics of unconfined cohesive powders in a rotating drum. Cohesion plays an important role, affecting flow properties/characteristics, mixing rates, and segregation tendencies. The method relies on measuring the change in center of mass of the powder bed as it avalanches...
Article
Heat transfer in particulate materials affects a wide variety of applications ranging from multi-phase reactors to kilns and calciners. In catalyst manufacturing, heat transfer through granular media (catalyst) occurs in the impregnation and calcinations stages. We use the discrete element model to simulate flow, mixing, and heat transport in granu...
Article
Rotary drums are used as mixers, dryers, kilns and granulators. In all of these systems, powder cohesion deeply affects mixing and segregation, and it is critical in process scale up. In this paper, we focus on the effect of cohesion in mixing and size segregation of binary mixtures of uniform and non-uniform sizes in a partially filled rotating dr...
Article
The flow dynamics of cohesive powders is investigated in rotating cylinders with an L : R ratio of 3 : 1 using experiments and DEM simulations. Flow onset and steady-state behavior are compared for free-flowing (cohesionless) dry glass beads, wet glass beads, and “dry” cohesive powders (lactose, microcrystalline cellulose). The avalanching dynamics...