Gly-His-Leu-Leu-Cys coated CdS quantum dots detected Cu2+ and Ag+ selectively with high sensitivity, below 0.5 microM.

A new peptidyl fluorescent chemosensor for the selective detection of copper ions was studied.

Layer-by-layer (LbL) assembly has been utilized to fabricate an ultrathin film of polyelectrolytes. The architecture was composed chitosan and organophosphorus hydrolase polycations along with thioglycolic acid-capped CdSe quantum dots (QDs) as the polyanion. topography films studied using epifluorescence microscopy imaging. photoluminescence property functionalized QDs improved when sandwiched between polycation layers. enhanced optical allowed easy monitoring LbL growth detection paraoxon...

A polyelectrolyte architecture was fabricated that composed of chitosan and organophosphorus hydrolase polycations along with thioglycolic acid-capped CdSe quantum dots (QDs) as the polyanion. This film imaged by epifluorescence microscopy. UV−vis emission spectroscopies were used to monitor growth bilayer due enhanced optical property QDs. Photoluminescence functionalized QDs improved when sandwiched between layers. The presence compounds confirmed through photoluminescence spectroscopy.

In this study, we demonstrate the applicability of functionalized alginate to serve as a platform for covalent cross-linking or immobilization complementary phosphine groups via chemoselective Staudinger ligation scheme. Azide were covalently linked through heterobifunctional polyethylene glycol (PEG) linker and carbodiimide. Degree azide functionalization was varied function carbodiimide concentration determined by proton nuclear magnetic resonance (1H NMR) infrared spectroscopy....

Encapsulation of viable tissues via layer-by-layer polymer assembly provides a versatile platform for cell surface engineering, with nanoscale control over the capsule properties. Herein, we report development hyperbranched polymer-based, ultrathin architecture expressing bioorthogonal functionality and tailored physiochemical Random carbodiimide-based condensation 3,5-dicarboxyphenyl glycineamide on alginate yielded highly branched polysaccharide multiple, spatially restricted, readily...

Langmuir film properties, UV-vis spectroscopy, epifluorescence microscopy, and transmission electron microscopy were used to study CdSe quantum dots (QDs) in 2D. By combining these results, it was possible determine the molar absorptivity, limiting nanoparticle area, luminescence property, arrangement of QDs monolayer films at air-water interface. Either trioctylphosphine oxide (TOPO) or 1-octadecanethiol (ODT) stabilized QDs. The data collected reveal that TOPO forms close-packed monolayers...

Gelatin having p-nitrocinnamate pendant groups (Gel-NC) was prepared via an efficient one-pot synthesis, yield >87%. (1)H NMR data indicated that 1 mol of gelatin modified with 18 +/- 6 the photosensitive group. Upon exposure to low-intensity 365 nm UV light and in absence photoinitiators or catalysts, Gel-NC cross-linked within minutes into a gelatin-based hydrogel as monitored by UV-vis spectroscopy. The degree swelling this biodegradable aqueous solutions responded changes concentration...

Hyperbranched functionalized polymers, coated onto capsules in a covalent layer-by-layer manner, provide facile platform for modulation of hydrogel permselectivity and stability.

In type 1 diabetes, the replacement of destroyed beta cells could restore physiological glucose regulation and eliminate need for exogenous insulin. Immunoisolation these foreign cellular transplants via biomaterial encapsulation is widely used to prevent graft rejection. While highly effective in blocking direct cell-to-cell contact, nonspecific inflammatory reactions implant lead overproduction reactive oxygen species, which contribute body reaction encapsulated cell loss. For antioxidant...

An inorganic/organic composite hybrid nano-system has been successfully synthesized in which nanocrystalline quantum dots (QDs) were effectively immobilized within a photo-cross-linked poly(ethylene glycol) (PEG) hydrogel. The immobilization of 3.5−6.0 nm CdTe and 2.0−3.5 CdSe QDs the PEG hydrogel network shown to be effective through utilization physical trapping. These QD-immobilized gel systems demonstrated luminescence characteristics unique semiconductor QD nanocrystals. Controlled...

Trioctylphosphine oxide- (TOPO-) capped (CdSe)ZnS quantum dots (QDs) were prepared through a stepwise synthesis. The surface chemistry behavior of the QDs at air-water interface was carefully examined by various physical measurements. pressure-area isotherm Langmuir film gave an average diameter 4.4 nm, which matched very well with value determined transmission electron microscopy (TEM) measurements if thickness TOPO cap counted. stability tested two different methods,...

Islet cell transplantation can lead to insulin independence, reduced hypoglycemia, and amelioration of diabetes complications in patients with type 1 diabetes. The systemic delivery anti-inflammatory agents, while considered crucial limit the early loss islets associated intrahepatic infusion, increases burden immunosuppression. In an effort decrease pharmaceutical load patient, we modified pancreatic islet surface long-chain poly(ethylene glycol) (PEG) mitigate detrimental host-implant...

Cellular encapsulation within alginate hydrogel capsules has broad applications in tissue engineering. In seeking to improve the inherent instability of ionically cross-linked hydrogels, we previously demonstrated covalent stabilization Ba(2+) alginate-azide beads via chemoselective Staudinger ligation using a 1-methyl-2-diphenylphosphino-terephthalate (MDT) terminated poly(ethylene glycol) (PEG) linker. this study, functionalized variant PEG, linear and branched, polymers with MDT groups...

Abstract Molecules of pentadecafluorooctanoyl chloride (PFC) were grafted onto alginate (Alg) using a linear poly(ethylene glycol) linker and amide bonds. The resulting Alg‐PFC material was characterized by proton nuclear magnetic resonance infrared spectroscopies. degree PFC functionalization significantly influenced the physical chemical properties Alg‐PFC, particularly when polymer ionically crosslinked into hydrogels. hydrogel beads fabricated via Ba 2+ crosslinking found to match...

For type 1 diabetics, islet transplantation can induce beneficial outcomes, including insulin independence and improved glycemic control. The long-term function of the grafted tissue, however, is challenged by host inflammatory immune responses. Cell encapsulation decrease detrimental responses to foreign implant, but standard microencapsulation imparts large transplant volumes impaired metabolite nutrient diffusion. To mitigate these effects, we developed an efficient covalent...

A polymeric hydrogel film was made photochemically for the fluorescent detection of copper ions. An eight-branched PEG macromer having a nitrocinnamate (NC) moiety as pendant group synthesized and found to form gel upon exposure 365-nm irradiation in absence any photoinitiators or catalysts. Peptide 1 (Dns-Gly-His-Lys(NC)) with Fmoc solid-phase method contained three essential parts:  dansyl fluorophore signal transduction, metal binding site selective recognition ions from aqueous solution,...