News

Spray freeze-drying of inhalable monoclonal antibodies: Enhancing stability and flowability

Lorena Pasero, Adamo Sulpizi, Tomaso Guidi, Roberto Pisano

Application of Natural Polymers to Enhance Probiotic Stability Following the Spray Freeze Drying Method

Marzieh Akrami, Mohammad Mahdi Omranpoor, Milad Imeni, Azadeh Emami, Vahid Ramezani

Abstract

Probiotics, defined as live microorganisms that confer health benefits on the host, are sensitive to environmental stresses. However, the stability of Lactobacillus casei during spray freeze drying (SFD) under different encapsulation conditions has not been thoroughly investigated. In various concentrations, the influence of three natural polymers, sodium alginate, xanthan gum, and chitosan, is evaluated on the stability and physicochemical properties of SFD-processed Lactobacillus casei powder at different storage temperatures, 4 °C, 25 °C, and 40 °C, for 90 days, as well as probiotic stability in simulated gastric and bile-containing media. In addition, the particles’ physicochemical properties are evaluated by tap density, FTIR, SEM, and DSC analysis. Probiotic microparticles after SFD are composed of a highly porous amorphous phase of polymers and various polymorphous structures of sucrose. Data shows that bacterial viability exceeds 90% immediately after SFD when low sodium alginate or xanthan gum concentrations were used. In addition, chitosan negatively impacts probiotic viability. However, applying a higher polymer ratio is problematic in long-term storage and contact with gastric fluid.

Keywords:

Probiotic viability; Sodium alginate; Spray freeze drying; Xanthan gum.

Translucent TZP ceramics prepared by sintering freeze-granulated nanopowders

Wei Wei

Abstract

In order to obtain translucent tetragonal zirconia polycrystalline (TZP) ceramics, complete densification, and homogeneous microstructure free of agglomerates and residual pores are required. To achieve this goal, freeze granulation of the zirconia nanopowder was performed. A series of stable and homogeneous zirconia suspension without agglomerates was prepared, by varying the solids loading volume percentage, to study the influence of the suspension characteristics on the freeze granulation behaviors. The characteristics of the prepared powder granules in terms of their size, flowability, and packing behaviors were subsequently analyzed. Uni-axial dry-pressing of the optimal granulate was used to prepare ceramic green bodies, which demonstrated the level of high strength and rigidness suitable for green milling based on the principle of computer aided design (CAD) and computer aided machining (CAM). Green bodies were sintered in air under conventional pressure-less condition. The sample sintered at 1400oC demonstrated a high optical translucency.

Keywords:

Freeze granulation

Design and DEM simulation analysis of the rotary freeze dryer in dynamic spray freeze-drying equipment

Runling Peng ,Zhan Gao, Haonan Zhai, Jinyue Liu, Wei Wang, Jinjuan Sun, Yunbo Shen

Abstract

For spray freeze-drying (SFD) powder materials, traditional static drying is not conducive to heat and mass transfer due to the accumulation of dried layers, resulting in low drying efficiency and difficulty in large-scale production. In order to improve the drying efficiency of SFD in the preparation nano-powders, a rotary freeze dryer was designed, and the simulation models of the drum and material particles by motion dynamics were constructed. The structural and process parameters of the drum were optimized by the Engineering Data Exchange Model (EDEM) simulation analysis. The results indicate that the optimal dispersion of material particles in the drum was achieved with a shovel plate tilt angle of 5°, 18 shovel plates, and a rotational speed of 33 r/min, yielding a maximum dispersion uniformity rate of the material particles is 94%. When the radian of the discharge blade was set to 7π/36 and the rotational speed to 25 r/min, the discharge rate reached its peak 2.25 kg/s. Furthermore, a 3D-printed drum was used for loading rotation experiment, and a comparison between the experimental and simulation results for the loading rotation of the drum was made. It was found that the simulation results are consistent with the experimental results of the motion state of material particles, and the relative error rate of the discharge rate is 4.16%. This confirms the validity of the simulation model and provides a theoretical foundation for the design of rotary freeze dryer.

Keywords:

Spray freeze-drying, drum, EDEM, numerical simulation, optimal design

Effects of spray freeze drying and pulsed electric fields on fenugreek seed extract properties

Butti Prabhakar, Raghupatruni Venkateswara Prasad

Abstract

Plant extracts are increasingly recognized for their potential health benefits, creating a growing demand for efficient extraction and preservation methods. In this study, a pulsed electric field (PEF) system was applied to maximize the extraction of plant bioactives, followed by encapsulation using spray freeze drying (SFD), a novel preservation technique. Among solvents tested, ethanol yielded the highest extract recovery (166.66 mg GAE/g), whereas methanol (sample-to-solvent ratio 1:10) resulted in the highest total polyphenol content. In the encapsulation process, gum acacia (GUA) at a 1:6 extract-to-binder ratio with a 30-hour lyophilization period produced powders with the lowest moisture content (3.9% w.b.), and SFD particles exhibited an average size of 9.0 μm. Furthermore, GUA as a binder and guar gum at a 20-hour lyophilization period achieved the highest polyphenol encapsulation efficiency. These findings highlight PEF-assisted extraction combined with SFD encapsulation as a cost-effective and efficient strategy for industrial-scale preservation of plant bioactives.

Keywords:

Pulsed electric field, spray freeze drying, encapsulation, gum acacia, plant extracts

An Innovative Formulation Development Approach of Sustained Release Matrix Tablet: A Review

S Gokulakrishnan, K. B. Ilango, Kalyan R, R Samyuktha, A Subash, K Subhashini

Abstract

This review delves about the various manufacturing process/ method of the sustained release matrix tablet & the methods are direct compression, wet granulation, dry granulation, foam granulation, freeze granulation, nanosponge, sintering method, 3D Printing. These all method possesses distinctive traits & unique benefits. The choice of process depends upon the specific formulation, desired tablet characteristic and production scale. In these methods, the solid medicaments are distributed throughout the porous matrix formed by the polymer which controls the medicament releasing & there is a presence of a novel strategy for prolonging drug release is the disintegration-controlled matrix, which maintains release for up to 24 hours by regulating the tablets breakdown rate. This review also discusses about the formulation of sustained release matrix tablet by using Quality by Design (QbD) & their dissolution patterns is indirectly detected by using the AI tool.

Keywords:

Sintering, Nano sponge, 3-D Printing, DCMT (Disintegration Controlled Matrix Tablet), Sustained-Release, Artificial intelligence.

Freeze-Drying Granulation of Non-Aqueous Nitride Slurry

Riko YAMAZAKI , Junichi TATAMI

Abstract

To apply the spray freeze granulation drying technique for nitride fabrication, we prepared silicon nitride slurries using a mixture of tert-butyl alcohol and cyclohexane as a solvent and attempted to understand the internal structural changes of the slurries by observing their freezing behavior. In addition, the ceramics were prepared using granules obtained via the spray freeze granulation drying method. It was found that the microstructures of the freeze-dried bodies differed depending on the solvent mixture ratio and the structure of the organic additive.

Keywords:

Freeze granulation, freeze-dried

A Review of Recent Techniques for Granulation

Thalari Sravani

Abstract

Granulation is the process of designing particles by combining primary power particles into massive multiparticle structures known as granules. Its primary purposes are to boost the flow of power, prevent segregation, improve the compaction characteristics of mix uniformity, and improve the flow and compressibility of powders. It also produces a combination that is uniform. Wet granulation and dry granulation are the two primary categories of granulation methods. The granulation process is contingent upon the description of the ingredient entity and its ability to surge appropriately, compact, and collapse. Choosing the appropriate granulation method necessitates a methodical examination of each ingredient in the combination and how they interact. Granule particle size is determined by the amount and feeding rate of the granulating liquid. New methods have been added to the granulation process to improve it: foam binder granulation, fluidized bed granulation, melt granulation, activated dry granulation, heat adhesion granulation, steam granulation, spray drying granulation, and freeze granulation. The major purpose of this page is to provide an overview of each advancement, including its limitations and relevance.

Keywords:

Granulation, foam granulation, stream granulation, thermal adhesion granulation

Fabrication of hollow MgO granules via freeze granulation as a filler for lightweight thermal interface materials

Rokhyeon Kim, Yunha Lee, Joo-Hwan Han, Chee-Sung Park & Jungho Ryu

Abstract

With the improvement in the performance of electric vehicles (EVs), heat generation by the battery increases, potentially leading to a number of issues; thus, the thermal management of high-performance secondary batteries is crucial. Thermal interface materials (TIMs) are polymer composites constituting high-thermal-conductivity fillers homogeneously dispersed in a polymer matrix. The thermal conductivity of TIMs is strongly affected by the thermal properties, size, shape, and content of the filler. As the weight of an EV directly impacts its fuel efficiency, new fillers with high thermal conductivity, low density, and cost-effectiveness must be developed for next-generation EVs. In this study, freeze granulation was used to fabricate highly thermally conductive, lightweight hollow MgO granules for low-density TIMs. Hollow MgO granules were fabricated by dispersing polymethyl methacrylate (PMMA) microbeads in a Mg(OH)₂ slurry, freeze-granulating the slurry, and removing PMMA through sintering to create hollow MgO spherical-shaped granules. The heating rate during PMMA removal, the PMMA microbead content, and the solid content of the Mg(OH)₂ in the slurry were adjusted to fabricate ideal hollow spherical-shaped granules. A TIM made with spherical hollow MgO granules (average diameter of 15–20 µm) fabricated through freeze granulation showed approximately 1% lower density and about 9% higher thermal conductivity than a TIM with solid MgO granules.

Keywords:

MgO
Hollow granule
Thermal interface material
Freeze granulation
Thermal conductivity

An Innovative Formulation Development Approach of Sustained Release Matrix Tablet: A Review

S Gokulakrishnan, K B Ilango, R Kalyan, R Samyuktha, A Subash, K Subhashini

Abstract

This review delves about the various manufacturing process/ method of the sustained release matrix tablet & the methods are direct compression, wet granulation, dry granulation, foam granulation, freeze granulation, nanosponge, sintering method, 3D Printing. These all method possesses distinctive traits & unique benefits. The choice of process depends upon the specific formulation, desired tablet characteristic and production scale. In these methods, the solid medicaments are distributed throughout the porous matrix formed by the polymer which controls the medicament releasing & there is a presence of a novel strategy for prolonging drug release is the disintegration-controlled matrix, which maintains release for up to 24 hours by regulating the tablets breakdown rate. This review also discusses about the formulation of sustained release matrix tablet by using Quality by Design (QbD) & their dissolution patterns is indirectly detected by using the AI tool. Keywords: Sintering, Nano sponge, 3-D Printing, DCMT (Disintegration Controlled Matrix Tablet), Sustained-Release, Artificial intelligence.

Keywords:

Freeze granulation, dry granulation, foam granulation, wet granulation, nanosponge