Diversity of PEGylation methods of liposomes and their influence on RNA delivery.

Gene therapy is a promising approach for personalized medicine, but its application in humans requires development of efficient and safe vehicles. PEGylated liposomes are some of the most suitable delivery systems for nucleic acids because of their stability under physiological conditions and prolonged circulation time, compared to conventional and other types of "stealth" liposomes. In vitro/in vivo activity of PEGylated liposomes is highly dependent on PEG motif abundance. The process of "stealth" coverage formation is a very important parameter for efficient transfection assays and further fate determination of the PEG layer after tissue penetration. In this review, we discuss the latest methods of PEGylated liposome preparation.

On the use of an optoacoustic and laser ultrasonic imaging system for assessing peripheral intravenous access.

We describe a universal system for research in combined real-time optoacoustic (OA) and laser-ultrasonic (LU) imaging. The results of its testing on the task of needle insertion into the blood vessel model diagnostics are presented. In OA mode, where laser light is absorbed directly in the sample, the contents of blood vessel model is clearly visible. In LU mode, where the short ultrasonic probe pulse scattered on the sample is detected, the needle is clearly visible. The developed solution combining OA and LU imaging modalities due to the common detection system allowed real-time diagnostics of the position of medical needles (0.63 mm and 0.7 mm in diameter) inside blood vessel models (1.6 mm and 2.4 mm in diameter). Frame rate was 10 Hz. High longitudinal spatial resolution of the system - 0.1 mm - allows distinguishing the two walls of the vessel model and the position of the needle inside.