Quantitative evaluation of oligonucleotide surface concentrations using polymerization-based amplification

Quantitative evaluation of minimal polynucleotide concentrations has become a critical analysis among a myriad of applications found in molecular diagnostic technology. Development of high-throughput, nonenzymatic assays that are sensitive, quantitative and yet feasible for point-of-care testing are thus beneficial for routine implementation. Here, we develop a nonenzymatic method for quantifying surface concentrations of labeled DNA targets by coupling regulated amounts of polymer growth to complementary biomolecular binding on array-based biochips. Polymer film thickness measurements in the 20–220 nm range vary logarithmically with labeled DNA surface concentrations over two orders of magnitude with a lower limit of quantitation at 60 molecules/μm2 (∼106 target molecules). In an effort to develop this amplification method towards compatibility with fluorescence-based methods of characterization, incorporation of fluorescent nanoparticles into the polymer films is also evaluated. The resulting gains in fluorescent signal enable quantification using detection instrumentation amenable to point-of-care settings

Facile control of nanoporosity in Cellulose Acetate using Nickel(II) nitrate additive and water pressure treatment for highly efficient battery gel separators

We succeed in fabricating nearly straight nanopores in cellulose acetate (CA) polymers for use as battery gel separators by utilizing an inorganic hexahydrate (Ni(NO3)2??6H2O) complex and isostatic water pressure treatment. The continuous nanopores are generated when the polymer film is exposed to isostatic water pressure after complexing the nickel(II) nitrate hexahydrate (Ni(NO3)2??6H2O) with the CA. These results can be attributed to the manner in which the polymer chains are weakened because of the plasticization effect of the Ni(NO3)2??6H2O that is incorporated into the CA. Furthermore, we performed extensive molecular dynamics simulation for confirming the interaction between electrolyte and CA separator. The well controlled CA membrane after water pressure treatment enables fabrication of highly reliable cell by utilizing 2032-type coin cell structure. The resulting cell performance exhibits not only the effect of the physical morphology of CA separator, but also the chemical interaction of electrolyte with CA polymer which facilitates the Li-ion in the cell.ope

Bisphosphonic Acid-Functionalized Cross-Linkers to Tailor Hydrogel Properties for Biomedical Applications

Two bisphosphonic acid-functionalized cross-linkers (one novel) with different spacer chain characteristics were synthesized and incorporated into hydrogels by copolymerization with 2-hydroxyethyl methacrylate at different ratios to control the hydrogels' swelling, mechanical properties, and ability to support mineralization for biomedical applications. The cross-linkers were synthesized by reaction of 2-isocyanatoethyl methacrylate and bisphosphonated diamines followed by selective dealkylation of the bisphosphonate ester groups. The hydrogels provide in vitro growth of carbonated apatite, morphology affected by the cross-linker structure. The hydrogels exhibit a high Young's modulus E (up to 400 kPa) and can sustain up to 10.2 +/- 0.1 MPa compressive stresses. E and hence the cross-link density significantly increases upon mineralization reflecting the formation of many bisphosphonate BP-Ca2+ bonds acting as additional cross-links. Cyclic mechanical tests reveal self-recoverability of hydrogels because of reversible nature of BP-Ca2+ bonds. The results suggest that these cross-linkers can add calcium-binding abilities to hydrogels synthesized from any monomer and improve their mechanical, swelling, and mineralization properties and hence are potentially useful materials for biomedical applications.Bogazici University Research FundBogazici University [11820]; Turkish Academy of Sciences (TUBA)Turkish Academy of SciencesThe authors would like to acknowledge the financial support from Bogazici University Research Fund (11820). O.O. thanks the Turkish Academy of Sciences (TUBA) for the partial support.WOS:0004406179000222-s2.0-85050974067PubMed: 3145899