Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Precipitate Formation and Particle Size Control

Precipitate Formation and Particle Size Control

In precipitation gravimetry, the precipitating agent should react specifically or selectively with the analyte. While a specific reagent reacts with the analyte alone, a selective reagent can react with a limited number of chemical species.
The obtained precipitate should be either a pure substance of known composition or easily converted to one by a simple process, such as ignition or drying. In addition, the precipitate should be insoluble and easily filterable. In general, filterability...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Elucidating the role of TPGS in felodipine/PVPVA amorphous solid dispersions during water uptake: dissipative particle dynamics simulations using quantum chemistry-based interaction parameters.

International journal of pharmaceutics·2026

Same author

Enhancing the Physicochemical Properties of Trimethoprim through Complexation with Sulfathiazole.

ACS omega·2026

Same author

Dynamical Fragment Molecular Orbital Interaction Analysis of SARS-CoV‑2 RNA-Dependent RNA Polymerase and Remdesivir.

ACS omega·2025

Same author

Identifying Robust Parameters for Flowability Analysis of Pharmaceutical Powders Using the Shear Cell Method.

Chemical & pharmaceutical bulletin·2025

Same author

Granulation Methods and the Mechanisms for Improving Hardness of Loxoprofen Sodium Hydrate-Containing Tablets.

Pharmaceutics·2025

Same author

Evaluation of the Mixing Characteristics of Magnesium Stearate Using Triboelectric Properties.

Chemical & pharmaceutical bulletin·2025

Search research articles

Related Experiment Video

Updated: Feb 24, 2026

Processing of Bulk Nanocrystalline Metals at the US Army Research Laboratory

Processing of Bulk Nanocrystalline Metals at the US Army Research Laboratory

Published on: March 7, 2018

Void forming index: A new parameter for detecting microstructural transformation caused by powder agglomeration.

Sunao Maruyama¹, Etsuo Yonemochi², Susumu Hasegawa³

¹Formulation Technology Research Laboratories, Pharmaceutical Technology Division, Daiichi Sankyo Co., Ltd., 1-12-1, Shinomiya, Hiratsuka, Kanagawa 254-0014, Japan; Department of Physical Chemistry, School of Pharmacy and Pharmaceutical Sciences, Hoshi University, 2-4-41, Ebara, Shinagawa-ku, Tokyo 142-8501, Japan.

International Journal of Pharmaceutics

|August 27, 2017

Summary

This summary is machine-generated.

Powder agglomeration in dry powder inhalers (DPIs) impacts performance. Inverse gas chromatography (iGC) detects agglomeration via pressure drop changes, leading to a new Void Forming Index (VFI) for DPI development.

Keywords:

Agglomeration Dry powder inhaler (DPI)Inverse gas chromatography (iGC)Pressure drop α-Lactose monohydrate

More Related Videos

Three-Dimensional Particle Shape Analysis Using X-ray Computed Tomography: Experimental Procedure and Analysis Algorithms for Metal Powders

Three-Dimensional Particle Shape Analysis Using X-ray Computed Tomography: Experimental Procedure and Analysis Algorithms for Metal Powders

Published on: December 4, 2020

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses

Published on: June 7, 2018

Related Experiment Videos

Last Updated: Feb 24, 2026

Processing of Bulk Nanocrystalline Metals at the US Army Research Laboratory

Processing of Bulk Nanocrystalline Metals at the US Army Research Laboratory

Published on: March 7, 2018

Three-Dimensional Particle Shape Analysis Using X-ray Computed Tomography: Experimental Procedure and Analysis Algorithms for Metal Powders

Three-Dimensional Particle Shape Analysis Using X-ray Computed Tomography: Experimental Procedure and Analysis Algorithms for Metal Powders

Published on: December 4, 2020

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses

Published on: June 7, 2018

Area of Science:

Pharmaceutical Sciences
Materials Science

Background:

Powder agglomeration during storage reduces dry powder inhaler (DPI) performance.
Capillary forces and crystalline transformations under humidity typically cause agglomeration.
Correlating limited crystalline transformation with agglomeration is challenging.

Purpose of the Study:

To investigate inverse gas chromatography (iGC) for direct detection of powder agglomeration.
To establish a novel index for evaluating powder agglomeration in DPI development.

Main Methods:

Utilized inverse gas chromatography (iGC) to measure lactose powder.
Employed powder X-ray diffraction (PXRD) and dynamic vapor sorption (DVS) for comparison.
Monitored pressure drop changes during iGC measurements.

Main Results:

iGC detected significant pressure drop changes in lactose, unlike PXRD and DVS.
Lactose powder agglomerated after iGC measurement, correlating with pressure drop.
A novel Void Forming Index (VFI) was developed based on iGC pressure drop.

Conclusions:

Pressure drop changes during iGC measurement indicate powder agglomeration onset.
The Void Forming Index (VFI) offers a valuable tool for assessing powder agglomeration.
VFI can aid in the development and optimization of dry powder inhalers.