TY - JOUR AB - We study the dimerization of the buckycatcher in gas phase and in toluene. We created an extensive library of 36 different complexes, which were characterized at semi-empirical and DFT levels. Semi-empirical geometries and dimerization energies compare well against reference data or Density Functional Theory calculations we performed. Born-Oppenheimer molecular dynamics was used to understand what happens when two molecules of the buckycatcher meet, allowing us to infer on the lack of kinetic barriers when dimers form. Thermodynamically, it is possible that room temperature solutions contain dimerized buckycatcher. Using a very simple exchange model, it is shown, however, that dimerization cannot compete thermodynamically against complexation with fullerenes, which accounts for experimental observations. AU - Cardoso Micu Menezes, F.M. AU - Popowicz, G.M. C1 - 68299 C2 - 54740 CY - Thomas Graham House, Science Park, Milton Rd, Cambridge Cb4 0wf, Cambs, England SP - 24031-24041 TI - When catchers meet - a computational study on the dimerization of the Buckycatcher. JO - Phys. Chem. Chem. Phys. VL - 25 IS - 35 PB - Royal Soc Chemistry PY - 2023 SN - 0956-5000 ER - TY - JOUR AB - Loss mechanisms in fluid heating of cobalt ferrite (CFO) nanoparticles and CFO-Pd heterodimer colloidal suspensions are investigated as a function of particle size, fluid concentration and magnetic field amplitude. The specific absorption rate (SAR) is found to vary with increasing particle size due to a change in dominant heating mechanism from susceptibility to hysteresis and frictional loss. The maximum SAR is obtained for particle diameters of 11-15 nm as a result of synergistic contributions of susceptibility loss, including Néel and Brownian relaxation and especially hysteresis loss, thereby validating the applicability of linear response theory to superparamagnetic CFO nanoparticles. Our results show that the ferrofluid concentration and magnetic field amplitude alter interparticle interactions and associated heating efficiency. The SAR of the CFO nanoparticles could be maximized by adjusting the synthesis parameters. Despite the paramagnetic properties of individual palladium nanoparticles, CFO-Pd heterodimer suspensions were observed to have surprisingly improved magnetization as well as SAR values, when compared with CFO ferrofluids. This difference is attributed to interfacial interactions between the magnetic moments of paramagnetic Pd and superparamagnetic/ferrimagnetic CFO. SAR values measured from CFO-Pd heterodimer suspensions were found to be 47-52 W gFerrite-1, which is up to a factor of two higher than the SAR values of commercially available ferrofluids, demonstrating their potential as efficient heat mediators. Our results provide insight into the utilization of CFO-Pd heterodimer suspensions as potential nanoplatforms for diagnostic and therapeutic biomedical applications, e.g., in cancer hyperthermia, cryopreserved tissue warming, thermoablative therapy, drug delivery and bioimaging. AU - Shams, S.F.* AU - Ghazanfari, M.R.* AU - Pettinger, S. AU - Tavabi, A.H.* AU - Siemensmeyer, K.* AU - Smekhova, A.* AU - Dunin-Borkowski, R.E.* AU - Westmeyer, G.G. AU - Schmitz-Antoniak, C.* C1 - 60824 C2 - 49638 CY - Thomas Graham House, Science Park, Milton Rd, Cambridge Cb4 0wf, Cambs, England SP - 26728-26741 TI - Structural perspective on revealing heat dissipation behavior of CoFe2O4-Pd nanohybrids: Great promise for magnetic fluid hyperthermia. JO - Phys. Chem. Chem. Phys. VL - 22 IS - 46 PB - Royal Soc Chemistry PY - 2020 SN - 0956-5000 ER - TY - JOUR AB - The development of suitable contrast agents can significantly enhance the efficiency of modern imaging and treatment techniques, such as thermoacoustic (TA) tomography and radio-frequency (RF) hyperthermia of cancer. Here, we examine the heating of aqueous suspensions of silicon (Si) and gold (Au) nanoparticles (NPs) under RF irradiation in the MHz frequency range. The heating rate of aqueous suspensions of Si NPs exhibited non-monotonic dependency on the electrical conductivity of the suspension. The experimental results were explained by the mathematical model considering oscillating solvated ions as the main source of Joule heating. These ions could be the product of the dissolution of Si NPs or organic coating of Au NPs. Thus, the ions governed the conductivity of the suspensions, which in turn governs both the heating rate and the near-field RF TA response. The model predicted the contrast in different tissues taking into account both Joule heating and dielectric losses. AU - Tamarov, K.* AU - Gongalsky, M. AU - Osminkina, L.* AU - Huang, Y. AU - Omar, M. AU - Yakunin, V.* AU - Ntziachristos, V. AU - Razansky, D. AU - Timoshenko, V.* C1 - 50968 C2 - 42928 CY - Cambridge SP - 11510-11517 TI - Electrolytic conductivity-related radiofrequency heating of aqueous suspensions of nanoparticles for biomedicine. JO - Phys. Chem. Chem. Phys. VL - 19 IS - 18 PB - Royal Soc Chemistry PY - 2017 SN - 0956-5000 ER - TY - JOUR AB - The amyloid beta-peptide (A beta) is the major structural component of amyloid fibrils in the plaques of brains of Alzheimer's disease patients. Numerous studies have addressed important aspects of secondary and tertiary structure of fibrils. In electron microscopic images, fibrils often bundle together. The mechanisms which drive the association of protofilaments into bundles of fibrils are not known. We show here that amino acid side chain exchangeable groups like e. g. histidines can provide useful restraints to determine the quarternary assembly of an amyloid fibril. Exchangeable protons are only observable if a side chain hydrogen bond is formed and the respective protons are protected from exchange. The method relies on deuteration of the A beta peptide. Exchangeable deuterons are substituted with protons, before fibril formation is initiated. AU - Agarwal, V.* AU - Linser, R.* AU - Dasari, M. AU - Fink, U.* AU - Lopez del Amo, J.M. AU - Reif, B. C1 - 26577 C2 - 32282 SP - 12551-12557 TI - Hydrogen bonding involving side chain exchangeable groups stabilizes amyloid quarternary structure. JO - Phys. Chem. Chem. Phys. VL - 15 IS - 30 PB - Royal Soc. Chemistry PY - 2013 SN - 0956-5000 ER - TY - JOUR AU - Chiappe, C.* AU - Lenoir, D. AU - Pomelli, C.S.* AU - Bianchini, R.* C1 - 5069 C2 - 21892 SP - 3235-3240 TI - Influence of alkene structure on the stability of alkene-Br2 complexes: Effect of chlorine substitution. JO - Phys. Chem. Chem. Phys. VL - 6 PY - 2004 SN - 0956-5000 ER -