1.Comprehensive overview of recent preparation and application trends of various open tubular capillary columns in separation science.
Cheong WJ1, Ali F, Kim YS, Lee JW. J Chromatogr A. 2013 Sep 20;1308:1-24. doi: 10.1016/j.chroma.2013.07.107. Epub 2013 Aug 5.
Open tubular (OT) capillary columns have been increasingly used in a variety of fields of separation science such as CEC, LC, and SPE. Especially their application in CEC has attracted a lot of attention for their outstanding separation performance. Various forms of OT stationary phase materials have been employed such as in-situ prepared polymers, molecular imprinted polymers (MIPs), brush ligands, host ligands, block copolymers, aptamers, carbon nanotubes, polysaccharides, proteins, tentacles, nanoparticles, monoliths, and polyelectrolyte multi-layers. They have been prepared either in the chemically bound format or physically adsorbed format. Sol-gel technologies and nanoparticles have been sometimes involved in their preparation. There have been also some unique miscellaneous studies, for example, adopting preferentially adsorbed mobile phase components as stationary phases. In this review, recent progresses since mostly 2007 will be critically discussed in detail with some summarized descriptions for the work before the date.
2.A dual sensor for real-time monitoring of glucose and oxygen.
Zhang L1, Su F, Buizer S, Lu H, Gao W, Tian Y, Meldrum D. Biomaterials. 2013 Dec;34(38):9779-88. doi: 10.1016/j.biomaterials.2013.09.031. Epub 2013 Oct 1.
A dual glucose and oxygen sensor in a polymer format was developed. The dual sensor composed of a blue emitter as the glucose probe, a red emitter as an oxygen probe, and a yellow emitter as a built-in reference probe which does not respond to either glucose or oxygen. All the three probes were chemically immobilized in a polyacrylamide-based matrix. Therefore, the dual sensor possesses three well separated emission colors and ratiometric approach is applicable for analysis of the glucose and oxygen concentration at biological conditions. The sensor was applied for real-time monitoring of glucose and oxygen consumption of bacterial cells, Escherichia coli (E. coli) and Bacillus subtilis (B. subtilis), and mammalian cells of mouse macrophage J774 and human cervical cancer HeLa cell lines. On the other hand, in order to achieve satisfactory sensing performance for glucose, compositions of the matrices among poly(2-hydroxyethyl methacrylate), polyacrylamide, and poly(6-aminohexyl methacrylamide) which is a linker polymer for grafting the glucose probe, were optimized.
3.Surfaces resistant to fouling from biological fluids: towards bioactive surfaces for real applications.
Rodriguez-Emmenegger C1, Houska M, Alles AB, Brynda E. Macromol Biosci. 2012 Oct;12(10):1413-22. doi: 10.1002/mabi.201200171. Epub 2012 Aug 28.
The fouling from four human body fluids - blood plasma, cerebrospinal fluid, urine and saliva - and four animal fluids - foetal bovine and calf sera, egg and milk - relevant to human and veterinary medicine, immunology, biology and diagnostics is assessed on antifouling SAMs and on polymer brushes of oligo(ethylene glycol) methacrylate, 2-hydroxyethyl methacrylate, carboxybetaine acrylamide and N-(2-hydroxypropyl)methacrylamide synthesized via ATRP. While important deposits from the all biofluids are observed on SAMs, a superior resistance is achieved on polymer brushes. Importantly, only poly(CBAA) and poly(HPMA) are capable of resisting the fouling from the most challenging media, blood plasma and eggs.
4.Biocomposites of pHEMA with HA/β -TCP (60/40) for bone tissue engineering: Swelling, hydrolytic degradation, and in vitro behavior.
Huang J1, Ten E, Liu G, Finzen M, Yu W, Lee JS, Saiz E, Tomsia AP. Polymer (Guildf). 2013 Feb 5;54(3):1197-1207. Epub 2012 Dec 21.
The field of bone and cartilage tissue engineering has a pressing need for novel, biocompatible, biodegradable biocomposites comprising polymers with bioceramics or bioglasses to meet numerous requirements for these applications. We created hydrolytically degradable hydrogel/bioceramic biocomposites, comprising poly(2-hydroxyethyl methacrylate) (pHEMA) hydrogels and 50 wt% biphasic hydroxyapatite/β-tricalcium phosphate (60/40) through in situ polymerization. The hydrolytic degradation starts with hydrolysis of the cross-linker, N, O-dimethacryloyl hydroxylamine, which was synthesized in house. Swelling and degradation were examined in details at a phosphate buffered saline solution at 37 °C over a 12-week period of time. To vary degradability, a co-monomer, acrylic acid (AA) or 2-hydroxypropyl methacrylamide (HPMA), was introduced, coupled with altering the concentration of the cross-linker and of the bioceramic. The co-monomer HPMA was found to be more effective than AA in enhancing degradation, though AA led to greater swelling ratios.