Miniatured Fluidics-Mediated Modular Self-Assembly of Anticancer Drug-Amino Acid Composite Microbowls for Combined Chemo-Photodynamic Therapy in Glioma

A particulate carrier with the ability to load a combination of therapeutic molecules acting via diverse modes to initiate cancer cell ablation would help heighten anticancer therapeutic outcomes and mitigate harmful side effects due to high doses of mono drug therapy. Moving a step closer, herein, we have developed doxorubicin-curcumin-amino acid-based composite microbowls (CMBs) following miniaturized fluid flow-based self-assembly. The CMBs were further exploited as dual chemo-photodynamic therapeutic agents in C6 glioma cells cultured in both two-dimensional (2D) monolayer and as three-dimensional (3D) spheroids. These CMBs showed synergistic and visible (blue)-light-sensitive cell-killing effects in both C6 cells and 3D spheroids. Furthermore, these bowl-shaped structures also demonstrated good stability and excellent in vitro cytocompatibility in C6 glioma cells. Our results indicated that CMBs with asymmetric cavities could potentially be used as a combinatorial drug carrier enabling simultaneous chemo- and phototherapy for effective cancer treatment. The use of blue light, from the visible part of the electromagnetic system, to generate the phototherapeutic effect further advocates for the ease and widespread applicability of the systems.

Microflow synthesis and enhanced photocatalytic dye degradation performance of antibacterial Bi2O3 nanoparticles

Microreactors can play a crucial role in synthesis and rapid testing of various nanocatalyst to be used in addressing the issue of environmental contamination. We have reported the rapid fabrication of polydimethylsiloxane (PDMS) and poly(methyl methacrylate) (PMMA)-based microreactor for the flow synthesis and enhanced inline photocatalysis of bismuth oxide (Bi₂O₃) nanoparticles. A T-shaped microreactor with uniform circular cross-sectional channel having inner diameter of 450 μm was utilized for synthesizing Bi₂O₃ nanoparticles with narrow size distribution. Further, photocatalytic dye degradation efficiency for methyl orange (MO) was recorded by coating these Bi₂O₃ nanoparticles within the inner walls of PMMA-based serpentine microreactors under visible light. The enhanced dye degradation efficiency of as high as 96% within just 15 min of irradiation is reported. A comparative analysis has also been done for both conventional as well as the in-channel photocatalysis highlighting the advantages of microreactor based photocatalysis over the conventional method. Bi₂O₃ nanoparticles also showed excellent stability even after three cycles indicating reusability of coated microreactors in photocatalysis. The small concentration of as synthesized Bi₂O₃ nanoparticles also demonstrated high efficacy for the inhibition of Escherichia coli bacterial pathogens.

Continuous flow fabrication of Fmoc-cysteine based nanobowl infused core-shell like microstructures for pH switchable on-demand anti-cancer drug delivery

Asymmetric nanostructures such as nanobowls (NBs) can exhibit superior drug delivery performances owing to their concave structure and interior asymmetric cavities. Here, we present a facile one-step method for the fabrication of NB like structures from a mere single amino acid mimetic, N-(9-fluorenylmethoxycarbonyl)-S-triphenylmethyl-l-cysteine following continuous-flow microfluidics enabled supramolecular self-assembly. Following fabrication, NBs were further infused into a vesicular shell consisting of the amino acid N-(tert-butoxycarbonyl)-S-triphenylmethyl-l-cysteine, carrying dual acid labile groups, the triphenylmethyl and the tert-butyloxycarbonyl groups. The NB infused core-shell like microstructures formed after the shell coating will now be addressed as NB-shells. Presence of pH-responsive shells bestowed the core-shell NB like structures with the ability to actively tune their surface pore opening and closing in response to environmental pH switch. To illustrate the potential use of the NB-shells in the field of anticancer drug delivery, the particles were loaded with doxorubicin (Dox) with an encapsulation efficiency of 42% and Dox loaded NB-shells exhibited enhanced efficacy in C6 glioma cells. Additionally, when tested in an animal model of glioblastoma, the nanoformulations demonstrated significantly higher retardation of tumour growth as compared to free Dox. Thus, this work strives to provide a new research area in the development of well turned-out and neatly fabricated pH switchable on/off anti-cancer drug delivery systems with significant translational potential.

Level of anxiety and dissociation in patients with conversion and dissociative disorders

State Trait Anxiety Inventory and Questionnaire of Experiences of Dissociation were administered to an unbiased sample of sixty patients, including twenty seven patients with dissociative disorder, twenty four with conversion disorder and nine with both these diagnoses, using DSM III criteria. The differences in anxiety scores and level of dissociation among the three diagnostic groups were not statistically significant. The finding that a substantial proportion (15%) of patients had both diagnoses and the lack of difference in levels of anxiety and dissociation in the three groups suggests that these two diagnoses are closely related.