Themed issue: Optofluidics

The term optofluidics defines a growing research area that integrates optics and microfluidics in ways that enable unique strengths and advantages for a broad range of applications. The First International Conference on Optofluidics (Optofluidics- 2011) organized by Xi’an Jiaotong University and Lab on a Chip on 11–12 December 2011 featured work in this field, with an exciting two-day program of presentations and discussions. We are happy that Lab on a Chip, a major publication destination for optofluidic research, has scheduled this themed issue on Optofluidics. We are especially heartened that the optofluidics community has responded enthusiastically with a large number of excellent manuscript submissions

UV-visible spectra character of larger diameter of gold nanoparticles (AuNPs)

The dependence of the optical properties of spherical gold nanoparticles (AuNPs) on particle size and wavelength were analyzed theoretically using Mie theory, where the complex refractive index of gold was corrected for the effect of a reduced mean free path of the conduction electrons in small particles. The simulation results indicated that larger diameter AuNPs have high sensitivity and the resolution compared to the small diameter AuNPs. Two different fabricated methods for synthesis larger diameter AuNPs have been proposed. One is the directly synthesis 50nm AuNPs, the other method is separated to two steps (prepared 13nm AuNPs seeds, then synthesis 50nm AuNPs). Comparing the UV-vis spectra and SEM image of the AuNPs synthesized by these two method, we find that the symmetry of the directly synthesis method is better than the other method. The experiment results show that the synthesis AuNPs are uniform. The major aim of this work is to provide a simple and fast method to synthesis larger diameter AuNPs and research the optical properties of the nanoparticles. © (2009) Trans Tech Publications

Quantum synchronization effects induced by strong nonlinearities

A paradigm for quantum synchronization is the quantum analog of the Stuart--Landau oscillator, which corresponds to a van der Pol oscillator in the limit of weak (i.e. vanishingly small) nonlinearity. Due to this limitation, the quantum Stuart--Landau oscillator fails to capture interesting nonlinearity-induced phenomena such as relaxation oscillations. To overcome this deficiency we propose an alternative model which approximates the van der Pol oscillator to finitely large nonlinearities while remaining numerically tractable. This allows us to uncover interesting phenomena in the deep-quantum strongly-nonlinear regime with no classical analog, such as the persistence of amplitude death on resonance. We also report nonlinearity-induced position correlations in reactively coupled quantum oscillators. Such coupled oscillations become more and more correlated with increasing nonlinearity before reaching some maximum. Again, this behavior is absent classically. We also show how strong nonlinearity can enlarge the synchronization bandwidth in both single and coupled oscillators. This effect can be harnessed to induce mutual synchronization between two oscillators initially in amplitude death.Comment: 6 pages, 3 figure

A Facile Nanodelivery Platform Based on Functionalized Hyperbranched Poly(ether-ester) for Individualized Antitumor Drugs: Pingyangmycin as a Model

Nanodelivery of antitumor drugs is a new treatment mode for cancer. The aim of this investigation was to construct and evaluate a facile nanodelivery platform for individualized antitumor drugs based on functionalized hyperbranched poly(ether-ester)s. Poly(ether-ester)s, as a kind of hyperbranched polymers, have received extensive attention. Three terminal-functionalized (OH–, NH2– and COOH–) hyperbranched poly(ether-ester)s were prepared and characterized by dynamic light scattering and attenuated total reflectance Fourier transform infrared spectroscopy. The relationship between chemical terminal variation and physical surface charges was investigated. Biocompatibility of these polymers was confirmed by methyl tetrazolium assays and scanning electron microscopy. As a model drug, pingyangmycin has antitumor and antiangiogenic effects. In the paper, pingyangmycin was mixed with carboxyl-modified hyperbranched poly(ether-ester) through ionic binding. Polymer-mixed pingyangmycin exhibited significant inhibition of HN-6 head and neck cancer human cells in vitro. These studies demonstrate that functionalized hyperbranched (ether-ester)s can be exploited as a facile nanodelivery platform for antitumor therapy

Use of blinatumomab and CAR T-cell therapy in children with relapsed/refractory leukemia: A case series study

BackgroundThe 5-year event-free survival rate for childhood acute lymphoblastic leukemia (ALL) has increased to more than 85%. However, the 5-year overall survival rate in children with relapsed/refractory ALL did not exceed 50%. In the past decade, immunotherapies (such as blinatumomab and chimeric antigen receptor T-cell therapy) were approved for relapsed/refractory B-ALL, transforming the treatment environment for children with relapsed/refractory ALL.ObjectiveThis study aimed to explore how immunotherapy can be incorporated into salvage regimens for pediatric patients with relapsed/refractory ALL by retrospectively analyzing the diagnosis and treatment process of seven children with relapsed/refractory leukemia and observing the side effects of the two strategies and long-term survival.MethodsThe clinical features and treatment responses of patients aged <14 years with relapsed/refractory leukemia who received immunotherapy (including Chimeric Antigen Receptor T cell treatment and blinatumomab) at Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology between February 2014 and April 2022 were retrospectively analyzed.ResultsSeven children underwent immunotherapy. Five patients received immunotherapy and sequential allogeneic hematopoietic stem cell transplantation (HSCT), whereas the other two received only immunotherapy. Five patients achieved complete remission (71.4%). None of the patients had severe cytokine release syndrome. However, one developed grade 3 immune effector cell-associated neurotoxicity syndrome with prior leukoencephalopathy. The median follow-up period was 541 days (range, 186–3,180 days). No deaths were related to treatment. Three patients relapsed, two had CD19-negative recurrences, and the third showed CD19 antigen reduction. One patient died after disease progression, whereas the other died of HSCT-related complications. One patient abandoned the treatment after relapse and was lost to follow-up.ConclusionBlinatumomab and CAR T-cell therapy showed excellent remission rates and manageable toxicity in pediatric patients with relapsed/refractory leukemia. However, the duration of the remission was limited. Therefore, further prospective randomized clinical studies should be conducted to improve the long-term efficacy of immunotherapy