Use of Atomic Force Microscopy (AFM) to monitor surface crystallization in caffeine-oxalic acid (CAFOXA) cocrystal compacts

Navpreet Kaur; Greg Haugstad; Raj Suryanarayanan

doi:10.1016/j.ijpharm.2021.121196

Use of Atomic Force Microscopy (AFM) to monitor surface crystallization in caffeine-oxalic acid (CAFOXA) cocrystal compacts

Navpreet Kaur, Greg Haugstad, Raj Suryanarayanan

Research output: Contribution to journal › Article › peer-review

1 Scopus citations

Abstract

Our objective was to monitor the surface crystallization in disordered caffeine-oxalic acid (CAFOXA) cocrystals following exposure to elevated water vapor pressure. This was accomplished using atomic force microscopy (AFM). Disorder was induced in the cocrystal particles by the common pharmaceutical unit operations of milling and compaction. The ‘activated’ solid, upon exposure to elevated water vapor pressure, had a high propensity to sorb water. This led to a rise in molecular mobility and the surface underwent rapid crystallization to form needle shaped crystals of CAFOXA. Using AFM height and phase imaging, we were able to directly visualize phase transformations on the compact surface. The milled compacts exhibited higher processing induced disorder than the unmilled compacts, thereby accelerating the surface recrystallization.

Original language	English (US)
Article number	121196
Journal	International journal of pharmaceutics
Volume	609
DOIs	https://doi.org/10.1016/j.ijpharm.2021.121196
State	Published - Nov 20 2021

Bibliographical note

Funding Information:
This work was supported by the William and Mildred Peters Endowment Fund. Parts of this work were carried out in the Characterization Facility, University of Minnesota, which receives partial support from NSF through the MRSEC program.

Publisher Copyright:
© 2021 Elsevier B.V.

Keywords

AFM
Cocrystals
Phase transformation
Surface disorder

PubMed: MeSH publication types

Journal Article

Access

10.1016/j.ijpharm.2021.121196

OpenUrl availability

Full text

Cite this

@article{da1a68a49c544f84a202a21686dec775,

title = "Use of Atomic Force Microscopy (AFM) to monitor surface crystallization in caffeine-oxalic acid (CAFOXA) cocrystal compacts",

abstract = "Our objective was to monitor the surface crystallization in disordered caffeine-oxalic acid (CAFOXA) cocrystals following exposure to elevated water vapor pressure. This was accomplished using atomic force microscopy (AFM). Disorder was induced in the cocrystal particles by the common pharmaceutical unit operations of milling and compaction. The {\textquoteleft}activated{\textquoteright} solid, upon exposure to elevated water vapor pressure, had a high propensity to sorb water. This led to a rise in molecular mobility and the surface underwent rapid crystallization to form needle shaped crystals of CAFOXA. Using AFM height and phase imaging, we were able to directly visualize phase transformations on the compact surface. The milled compacts exhibited higher processing induced disorder than the unmilled compacts, thereby accelerating the surface recrystallization.",

keywords = "AFM, Cocrystals, Phase transformation, Surface disorder",

author = "Navpreet Kaur and Greg Haugstad and Raj Suryanarayanan",

note = "Funding Information: This work was supported by the William and Mildred Peters Endowment Fund. Parts of this work were carried out in the Characterization Facility, University of Minnesota, which receives partial support from NSF through the MRSEC program. Publisher Copyright: {\textcopyright} 2021 Elsevier B.V.",

year = "2021",

month = nov,

day = "20",

doi = "10.1016/j.ijpharm.2021.121196",

language = "English (US)",

volume = "609",

journal = "International journal of pharmaceutics",

issn = "0378-5173",

publisher = "Elsevier",

}

TY - JOUR

T1 - Use of Atomic Force Microscopy (AFM) to monitor surface crystallization in caffeine-oxalic acid (CAFOXA) cocrystal compacts

AU - Kaur, Navpreet

AU - Haugstad, Greg

AU - Suryanarayanan, Raj

N1 - Funding Information: This work was supported by the William and Mildred Peters Endowment Fund. Parts of this work were carried out in the Characterization Facility, University of Minnesota, which receives partial support from NSF through the MRSEC program. Publisher Copyright: © 2021 Elsevier B.V.

PY - 2021/11/20

Y1 - 2021/11/20

N2 - Our objective was to monitor the surface crystallization in disordered caffeine-oxalic acid (CAFOXA) cocrystals following exposure to elevated water vapor pressure. This was accomplished using atomic force microscopy (AFM). Disorder was induced in the cocrystal particles by the common pharmaceutical unit operations of milling and compaction. The ‘activated’ solid, upon exposure to elevated water vapor pressure, had a high propensity to sorb water. This led to a rise in molecular mobility and the surface underwent rapid crystallization to form needle shaped crystals of CAFOXA. Using AFM height and phase imaging, we were able to directly visualize phase transformations on the compact surface. The milled compacts exhibited higher processing induced disorder than the unmilled compacts, thereby accelerating the surface recrystallization.

AB - Our objective was to monitor the surface crystallization in disordered caffeine-oxalic acid (CAFOXA) cocrystals following exposure to elevated water vapor pressure. This was accomplished using atomic force microscopy (AFM). Disorder was induced in the cocrystal particles by the common pharmaceutical unit operations of milling and compaction. The ‘activated’ solid, upon exposure to elevated water vapor pressure, had a high propensity to sorb water. This led to a rise in molecular mobility and the surface underwent rapid crystallization to form needle shaped crystals of CAFOXA. Using AFM height and phase imaging, we were able to directly visualize phase transformations on the compact surface. The milled compacts exhibited higher processing induced disorder than the unmilled compacts, thereby accelerating the surface recrystallization.

KW - AFM

KW - Cocrystals

KW - Phase transformation

KW - Surface disorder

UR - http://www.scopus.com/inward/record.url?scp=85117357854&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85117357854&partnerID=8YFLogxK

U2 - 10.1016/j.ijpharm.2021.121196

DO - 10.1016/j.ijpharm.2021.121196

M3 - Article

C2 - 34662647

AN - SCOPUS:85117357854

SN - 0378-5173

VL - 609

JO - International journal of pharmaceutics

JF - International journal of pharmaceutics

M1 - 121196

ER -

Use of Atomic Force Microscopy (AFM) to monitor surface crystallization in caffeine-oxalic acid (CAFOXA) cocrystal compacts

Abstract

Bibliographical note

Keywords

PubMed: MeSH publication types

Access

OpenUrl availability

Other files and links

Fingerprint

Cite this