Cryogenic transmission electron microscopy (cryo-TEM) for studying the morphology of colloidal drug delivery systems

2011 ◽  
Vol 417 (1-2) ◽  
pp. 120-137 ◽  
Author(s):  
Judith Kuntsche ◽  
Jennifer C. Horst ◽  
Heike Bunjes
2019 ◽  
Vol 9 (2) ◽  
pp. 47-56
Author(s):  
Madhubhai M Patel ◽  
Rahulkumar J Patel

The aim of the present investigation was to formulate and evaluate solid self-micro emulsifying drug-delivery systems (S-SMEDDS) to improve solubility and dissolution profile of Linagliptin. Solubility of Linagliptin in different oils, surfactants and co-surfactants was assessed and optimizations of pseudo-ternary plots were also carried out for preparation of liquid SMEDDS. D-optimal design mixture was used in the optimization of Linagliptin loaded liquid SMEEDS. The optimized SMEEDS were characterized for globule size, zeta potential, dilution stability, transmittance, pH and in-vitro release profile. The morphology of the Linagliptin SMEEDS was observed by Transmission Electron Microscopy (TEM). Among the different silicates, Nusillin US2 was used as the solid carrier/absorbent to formulate S-SMEEDS of Linagliptin. Improved in-vitro dissolution profile of optimized formulation was observed, resulting in multifold improvement in the absorption profile of Linagliptin as compared with pure drug. In a nutshell, this optimized S-SMEDD formulation holds great promise for enhancement of its physiochemical and biological attributes. Keywords: Linagliptin, Solid Self-micro Emulsifying Drug Delivery Systems, D-optimal design, Zeta-potential, Transmission Electron Microscopy


PRILOZI ◽  
2019 ◽  
Vol 40 (2) ◽  
pp. 67-72 ◽  
Author(s):  
Marija Petrushevska ◽  
Kristina Pavlovska ◽  
Jovanka Laskova ◽  
Pance Zdravkovski ◽  
Marija Glavas Dodov

Abstract Nanotechnology presents a modern field of science that in the last twenty-five years plays a dominant role in the biomedicine. Different analytical methods are used for evaluation of the physico-chemical properties of nanoparticles including chromatography, electrophoresis, X-ray scattering, spectroscopy, mass spectrometry, zeta potential measurement and microscopy on which this article will focus. Herein, we present novel application of the long-established TEM technique that is focused on characterization and evaluation of various nanoparticles in development of drug delivery systems. Transmission electron microscopy images were taken of samples from native nanoparticles, nanoparticles labeled using stannous chloride labeling procedure, inorganic silica nanoparticles loaded with budesonide and native micelles and micelles carrier of anticancer drug camptothecin. In the case of radiolabeled nanoparticles, beside for nanoparticle characterization, TEM technique was used to confirm the stability of the nanoparticles after radiolabeling. Furthermore, the porous structure of hybrid silica particles loaded with budesonide was examined under TEM. Transmission electron microscopy technique offers exceptional benefits for nanoparticle characterization. Additionally, the necessity of ultrastructural analysis demonstrates the potential of TEM in the field of nanomedicine. Hence, the long-established and well-known TEM has been only partially exploited and offer researchers very detailed images of specimens at microscopic and nano scale.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Bing Han ◽  
Yucheng Zou ◽  
Zhen Zhang ◽  
Xuming Yang ◽  
Xiaobo Shi ◽  
...  

AbstractCryogenic transmission electron microscopy (cryo-TEM) is a valuable tool recently proposed to investigate battery electrodes. Despite being employed for Li-based battery materials, cryo-TEM measurements for Na-based electrochemical energy storage systems are not commonly reported. In particular, elucidating the chemical and morphological behavior of the Na-metal electrode in contact with a non-aqueous liquid electrolyte solution could provide useful insights that may lead to a better understanding of metal cells during operation. Here, using cryo-TEM, we investigate the effect of fluoroethylene carbonate (FEC) additive on the solid electrolyte interphase (SEI) structure of a Na-metal electrode. Without FEC, the NaPF6-containing carbonate-based electrolyte reacts with the metal electrode to produce an unstable SEI, rich in Na2CO3 and Na3PO4, which constantly consumes the sodium reservoir of the cell during cycling. When FEC is used, the Na-metal electrode forms a multilayer SEI structure comprising an outer NaF-rich amorphous phase and an inner Na3PO4 phase. This layered structure stabilizes the SEI and prevents further reactions between the electrolyte and the Na metal.


Soft Matter ◽  
2021 ◽  
Vol 17 (11) ◽  
pp. 3096-3104
Author(s):  
Valeria Castelletto ◽  
Jani Seitsonen ◽  
Janne Ruokolainen ◽  
Ian W. Hamley

A designed surfactant-like peptide is shown, using a combination of cryogenic-transmission electron microscopy and small-angle X-ray scattering, to have remarkable pH-dependent self-assembly properties.


2016 ◽  
Vol 5 (6) ◽  
Author(s):  
Tuong Vi Tran ◽  
Uyen Vy Vo ◽  
Dong Yen Pham ◽  
Dai Lam Tran ◽  
Thi Hiep Nguyen ◽  
...  

AbstractPorous nanosilica (PNS) has been attracting much attention in fabrication of nanocarriers for a drug delivery system (DDS). However, the unmodified PNS-based carriers exhibited a significant initial burst release of drug, which may limit their potential clinical application. In this study, PNS was surface conjugated with cyclodextrin (CD) which was functionalized with adamantylamine-polyethylene glycol (APEG) for 5-fluorouracil (5-FU) delivery, in which case CD was used due to its ability to form a stable inclusion complex with 5-FU and APEG. The conjugated PNS (PNSC@APEG) was successfully prepared with spherical shape and diameter around 50 nm, determined by transmission electron microscopy (TEM). In addition, 5-FU was efficiently trapped in PNSC@APEG particles, which were around 63.4%±3.8% and was slowly released up to 3 days in phosphate buffer saline (PBS). Furthermore, the cell proliferation kit I (MTT) assay data showed that PNSC@APEG was a biocompatible nanocarrier. These results indicated that PNSC@APEG nanoparticles have a great potential as novel carriers for anticancer drug delivery.


Sign in / Sign up

Export Citation Format

Share Document