Preparation of Carbon nanotubes and Polyhedral oligomeric-Reinforced Molecularly Imprinted Polymer Composites for Drug Delivery of Gallic acid

In this paper, an enhanced imprinting effect of utilizing single wall carbon nanotubes (SWCNT) and polyhedral oligomeric silsesquioxanes (POSS) was suggested to improve drug delivery. The combination of 1-butyl-3-methylimidazoliumtetrafluoroborate ([BMIM]BF₄), tetrahydrofuran (THF) and choline chloride-ethylene glycol (ChCl / EG) were used as a ternary porogen to prepare molecularly imprinted polymer (MIPs) doped with SWCNT and POSS. In the presence of gallic acid (GAL), 4-vinylpyridine (4-VP) and ethylene glycol dimethacrylate (EDMA) was functional monomer and crosslinker, respectively. The structure and morphological parameters of the MIP composite, such as surface area and pore size distribution, were also measured. In the studies of in vitro releases, superior controlled release characteristics can be achieved due to the enhanced imprinting effect of the MIPs doped with POSS and SWCNT. In vivo release studies showed that the POSS-SWCNT MIP had the maximum plasma concentration after 4 hours. Compared with the control MIPs and NIP, the POSS-SWCNT MIP displayed a maximum AUC_0-9 of 544.73 (ng h mL^-1), while only 327.48, 212.91, 230.35 and 275.13 (ng h mL^-1) for the POSS MIP, SWCNT MIP, MIP and POSS-SWCNT NIP, respectively.

Magnetic nanoparticles in nanomedicine: a review of recent advances

Nanomaterials, in addition to their small size, possess unique physicochemical properties that differ from bulk materials, making them ideal for a host of novel applications. Magnetic nanoparticles (MNPs) are one important class of nanomaterials that have been widely studied for their potential applications in nanomedicine. Due to the fact that MNPs can be detected and manipulated by remote magnetic fields, it opens a wide opportunity for them to be used in vivo. Nowadays, MNPs have been used for diverse applications including magnetic biosensing (diagnostics), magnetic imaging, magnetic separation, drug and gene delivery, and hyperthermia therapy, etc. Specifically, we reviewed some emerging techniques in magnetic diagnostics such as magnetoresistive (MR) and micro-Hall (μHall) biosensors, as well as the magnetic particle spectroscopy, magnetic relaxation switching and surface enhanced Raman spectroscopy (SERS)-based bioassays. Recent advances in applying MNPs as contrast agents in magnetic resonance imaging and as tracer materials in magnetic particle imaging are reviewed. In addition, the development of high magnetic moment MNPs with proper surface functionalization has progressed exponentially over the past decade. To this end, different MNP synthesis approaches and surface coating strategies are reviewed and the biocompatibility and toxicity of surface functionalized MNP nanocomposites are also discussed. Herein, we are aiming to provide a comprehensive assessment of the state-of-the-art biological and biomedical applications of MNPs. This review is not only to provide in-depth insights into the different synthesis, biofunctionalization, biosensing, imaging, and therapy methods but also to give an overview of limitations and possibilities of each technology.

Restricted access carbon nanotubes for direct extraction of cadmium from human serum samples followed by atomic absorption spectrometry analysis

In this paper, we propose a new sorbent that is able to extract metal ions directly from untreated biological fluids, simultaneously excluding all proteins from these samples. The sorbent was obtained through the modification of carbon nanotubes (CNTs) with an external bovine serum albumin (BSA) layer, resulting in restricted access carbon nanotubes (RACNTs). The BSA layer was fixed through the interconnection between the amine groups of the BSA using glutaraldehyde as cross-linker. When a protein sample is percolated through a cartridge containing RACNTs and the sample pH is higher than the isoelectric point of the proteins, both proteins from the sample and the BSA layer are negatively ionized. Thus, an electrostatic repulsion prevents the interaction between the proteins from the sample on the RACNTs surface. At the same time, metal ions are adsorbed in the CNTs (core) after their passage through the chains of proteins. The Cd(2+) ion was selected for a proof-of-principle case to test the suitability of the RACNTs due to its toxicological relevance. RACNTs were able to extract Cd(2+) and exclude almost 100% of the proteins from the human serum samples in an online solid-phase extraction system coupled with thermospray flame furnace atomic absorption spectrometry. The limits of detection and quantification were 0.24 and 0.80 μg L(-1), respectively. The sampling frequency was 8.6h(-1), and the intra- and inter-day precisions at the 0.80, 15.0, and 30.0 μg L(-1) Cd(2+) levels were all lower than 10.1% (RSD). The recoveries obtained for human blood serum samples fortified with Cd(2+) ranged from 85.0% to 112.0%. The method was successfully applied to analyze Cd(2+) directly from six human blood serum samples without any pretreatment, and the observed concentrations ranged from <LOQ to 2.52 µg L(-1).