@article{xu_kleinstreuer_2018, title={Direct nanodrug delivery for tumor targeting subject to shear-augmented diffusion in blood flow}, volume={56}, ISSN={["1741-0444"]}, DOI={10.1007/s11517-018-1818-z}, abstractNote={The advent of multifunctional nanoparticle has enabled numerous innovative strategies in diagnostics, imaging, and cancer therapy. Despite the intense research efforts in developing new nanoparticles and surface bonding ligands, one major obstacle in achieving highly effective treatment, including minimizing detrimental side effects, is the inability to deliver drug-carrying nanoparticles from the injection point directly to the tumor site. The present study seeks to employ a direct nanodrug delivery methodology to feed multifunctional nanoparticles directly to tumor vasculatures, sparing healthy tissue. An important aspect to examine is how the interactions between such nanoparticles and relatively large red blood cells would affect the transport and delivery efficiency of nanodrugs. So, a novel computer simulation model has been developed to study nanoparticle transport in a representative human hepatic artery system, subject to shear-induced diffusion of nanoparticles due to hydrodynamic interactions with red blood cells. The particle-size effect was also evaluated by comparing the dynamics of nanoparticles with microspheres. Results from computer simulations under physiologically realistic conditions indicate that shear-induced diffusion has a significant effect on nanoparticle transport, even in large arteries. Nevertheless, as documented, direct nanodrug delivery to tumor-feeding hepatic artery branches is feasible. Graphical abstract Direct nanodrug delivery from injection point to tumor-feeding artery branch.}, number={11}, journal={MEDICAL & BIOLOGICAL ENGINEERING & COMPUTING}, author={Xu, Zelin and Kleinstreuer, Clement}, year={2018}, month={Nov}, pages={1949–1958} }
 @article{xu_jernigan_kleinstreuer_buckner_2016, title={Solid Tumor Embolotherapy in Hepatic Arteries with an Anti-reflux Catheter System}, volume={44}, ISSN={["1573-9686"]}, DOI={10.1007/s10439-015-1411-7}, abstractNote={Unresectable hepatoma accounts for the majority of malignant liver tumor cases for which embolization therapy is considered a viable treatment option. However, the potential risk of aberrant particle deposition in non-target regions could cause severe side-effects, alongside diminished efficacy. A computational model has been developed to analyze the particle-hemodynamics before and after deployment of an FDA-approved anti-reflux catheter. The catheter features a retractable, porous cone-like tip designed to allow forward blood flow while preventing microsphere reflux. A patient-specific hepatic artery system, with different daughter branches connected to a liver tumor, was chosen as a representative test bed. In vitro as well as in vivo measurements were used to validate the computer simulation model. The model captures the effect of tip-deployment on blood perfusion and pressure drop in an interactive manner under physiologically realistic conditions. A relationship between the pressure drop and embolization level was established, which can be used to provide clinicians with real-time information on the best infusion-stop point. However, the results show that the present procedure for embolization of downstream vessels which feed a tumor is quite arbitrary. Nevertheless, a method to recycle aberrant particles captured by the deployed tip was proposed to minimize side-effects.}, number={4}, journal={ANNALS OF BIOMEDICAL ENGINEERING}, author={Xu, Zelin and Jernigan, Shaphan and Kleinstreuer, Clement and Buckner, Gregory D.}, year={2016}, month={Apr}, pages={1036–1046} }
 @article{elek_zhang_dai_xu_chang_2015, title={Fabrication of three-dimensional hierarchical nanostructures using template-directed colloidal assembly}, volume={7}, ISSN={["2040-3372"]}, DOI={10.1039/c4nr06840h}, abstractNote={Optical effects in template-directed colloidal assembly are explored to fabricate microscale patterns with integrated three-dimensional (3D) nanostructures.}, number={10}, journal={NANOSCALE}, author={Elek, J. E. and Zhang, X. A. and Dai, B. and Xu, Z. and Chang, C. -H.}, year={2015}, pages={4406–4410} }
 @article{xu_kleinstreuer_2014, title={Concentration photovoltaic-thermal energy co-generation system using nanofluids for cooling and heating}, volume={87}, ISSN={["1879-2227"]}, DOI={10.1016/j.enconman.2014.07.047}, abstractNote={New designs of dual concentration photovoltaic–thermal (CPV/T) systems can provide both electrical and thermal energy, while reducing solar cell material usage via optical techniques. The overall system efficiency can be improved by using advanced dual-purpose liquids with enhanced heat transfer characteristics, such as nanofluids. In this paper the use of nanofluids, i.e., dilute nanoparticle suspensions in liquids, are considered for improved efficiency of a CPV/T system for the first time. Specifically, a 2-D model coupling thermal analysis and computational fluid dynamics simulations has been developed to calculate efficiencies of individual subsystems as well as the overall system. A new thermal conductivity model for nanofluids, which was validated with experimental data sets, was employed. The electrical and thermal performances of the system were evaluated for different climatic conditions. The results show that using nanofluids improves the electrical and total efficiencies of the system, especially when using silicon solar cells. For example, if the nanofluid outlet temperature of the solar cell is set to 62 °C via a controlled flow rate, the system overall efficiency could reach 70% with electrical and thermal contributions amounting to 11% and 59%, respectively. In summary, a nanofluid-based system is preferable to water-based systems in the long run.}, journal={ENERGY CONVERSION AND MANAGEMENT}, author={Xu, Zelin and Kleinstreuer, Clement}, year={2014}, month={Nov}, pages={504–512} }