Analytical Methods Blog

Lipid bilayer structure of the liposome

The small size and lipid bilayer structure of liposomes make them an excellent carrier for use in drug delivery and gene therapy. Determining the chemical and physical properties of a liposome is key to evaluating its potential for different applications.

A range of techniques have been used to measure factors such as size, surface charge and encapsulation efficiency of these spherical structures. In this minireview, Xiaomei Yan and colleagues at Xiamen University, China, explore recent advances in techniques for single-liposome characterization. They evaluate the latest adaptations of traditional microscopy techniques and investigate the advantages and limitations of using flow cytometry for characterisation. Recently developed commercial techniques such as scanning ion occlusion sensing (SIOS) and nanoparticle tracking analysis (NTA) also offer more advanced methods of single-liposome analysis.

To access the full article, please click on the link below. This paper will be free to read until May 14th.

Analytical techniques for single-liposome characterization
Chaoxiang Chen, Shaobin Zhu, Tianxun Huang, Shuo Wanga and   Xiaomei Yan  
Anal. Methods, 2013,5, 2150-2157
DOI: 10.1039/C3AY40219C

Recent applications of square wave voltammetry

In this Critical Review, Aicheng Chen and Badal Shah describe the latest developments in electrochemical biosensing based on square wave voltammetry (SWV).

Because of its high sensitivity and selectivity, SWV has been widely used for detection of disease-related biomarkers, environmental pollutants and food contaminants. The authors define the recent biosensors based on SWV as the next generation point of care diagnostic devices, and highlight the successful applications of SWV in food analysis, environmental monitoring and enzymes kinetics.

To read the full article, please access the link below. This paper will be free to read until April 25^th. Have a read!

Electrochemical sensing and biosensing based on square wave voltammetry
Aicheng Chen and Badal Shah
Anal. Methods, 2013, Advance Article
DOI: 10.1039/C3AY40155C

Synthesis of gold-antibody nanocomposite and AFP immunoassay

The construction of successful biosensors is often hampered by the difficulty of immobilising biomolecules onto the desired surface in an orderly fashion. As a support medium, nanoparticles display a particularly large surface-to-volume ratio and their physical properties can be adjusted to match requirements.

Researchers led by Zhihui Dai from the Nanjing Normal University, China, have used a liquid-liquid interface technique to immobilise Ab₁ antibodies onto gold nanoparticles, characterising the material using energy dispersive spectroscopy (EDS).

Detection of abnormal levels of alpha-fetoprotein (AFP) can indicate the presence of cancerous cells. In this work, a sandwich immunoassay was used to test the sensitivity of the Au-Ab₁ nanocomposite towards AFP, demonstrating good selectivity, stability and reproducibility of the sensor. In clinical samples, the gold-based sensor performed well against the current enzyme-linked immunosorbant assay (ELISA) method of testing.

Do you want to know more about this research? Click on the link below, this article will be free to read until April 19th:

Gold–antibody nanocomposite thin film fabricated by a liquid–liquid interface technique and its application for the sensitive immunoassay of alpha-fetoprotein
Kun Wang ,  Tianxiang Wei ,  Wenwen Tu ,  Min Han and Zhihui Dai
Anal. Methods, 2013,5, 1909-1914
DOI: 10.1039/C3AY26541B