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Layer-by-Layer (LbL) assembly of polyelectrolytes on a solid core particle is a well-established technique used to deliver drugs, proteins, regenerative medicines, combinatorial therapy, etc. It is a multifunctional delivery system which can be engineered using various core template particles and coating polymers. This study reports the development and in-vitro evaluation of LbL assembled particles for non-invasive inhaled delivery to the lungs. The LbL assembled particles were prepared by successively coating polyelectrolyte macromolecules, glycol chitosan and bovine serum albumin on 0.5- and 4.5-μm polystyrene particles. The LbL assembly of polyelectrolytes was confirmed by reversible change in zeta potential and sequential increase in the particle size after accumulation of the layer. The prepared LbL particles were further assessed for aerodynamic properties using two distinct nebulizers, and toxicity assessment in normal lung cells. The in-vitro aerosolization study performed using next generation impactor coupled with Pari LC Plus and Aeroeclipse nebulizer showed that both the LbL assembled 0.5 and 4.5-μm particles had MMAD <5 μm confirming suitable aerodynamic properties for non-invasive lung delivery. The in-vitro cytotoxicity, and TEER integrity following treatment with the LbL assembled particles in normal lung epithelial and fibroblasts showed no significant cytotoxicity rendering the LbL assembled particles safe. This study extends the efficiency of LbL assembled particles for novel applications towards delivery of small and large molecules into the lungs., Competing Interests: Declaration of competing interest All authors declare no conflict of interest in this work., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Activation of B and T lymphocytes leads to major remodelling of the metabolic landscape of the cells enabling their post-activation functions. However, naive B and T lymphocytes also show metabolic differences, and the genesis, nature and functional significance of these differences are not yet well understood. Here we show that resting B-cells appeared to have lower energy demands than resting T-cells as they consumed lower levels of glucose and fatty acids and produced less ATP. Resting B-cells are more dependent on OXPHOS, while T-cells show more dependence on aerobic glycolysis. However, despite an apparently higher energy demand, T lineage cells showed lower rates of protein synthesis than equivalent B lineage stages. These metabolic differences between the two lineages were established early during lineage differentiation, and were functionally significant. Higher levels of protein synthesis in B-cells were associated with increased synthesis of MHC class II molecules and other proteins associated with antigen internalization, transport and presentation. The combination of higher energy demand and lower protein synthesis in T-cells was consistent with their higher ATP-dependent motility. Our data provide an integrated perspective of the metabolic differences and their functional implications between the B and T lymphocyte lineages., (© 2019 John Wiley & Sons Ltd.)

A flow-through colorimetric assay for detection of nucleic acids in plasma is reported. The proposed assay features an array of four polyvinylidene fluoride (PVDF) membranes impregnated with cationic poly (3-alkoxy-4-methylthiophene) (PT) as an optical reporter. The sensing strategy is based on monitoring the changes in optical properties of PT, upon complexation with target nucleic acids in the presence and in the absence of their corresponding complementary peptide nucleic acids (PNAs). As a proof of concept, the proposed methodology is validated using two biomarkers; lung cancer associated microRNA (mir21) and hepatitis B virus DNA (HBV-DNA). The flow-through colorimetric assay enabled detection of mir21 and HBV-DNA in plasma without requiring tedious sample pre-treatment and clean up protocols. Colorimetric responses for mir21 and HBV-DNA were obtained at nanomolar concentrations over five orders of magnitudes (from 1 nM to 10 μM), with a limit of detection of ∼0.6 nM and ∼2 nM in DI water and plasma, respectively. A logic gate system was developed to utilize the colorimetric assay responses as inputs for discrimination of mir21 and HBV-DNA and subsequently to obtain a profile of nucleic acids in samples that exceed respective clinical threshold limits, thereby enabling rapid and point of care (POC) disease diagnosis. Furthermore, the proposed methodology can be utilized for detection of a large number of nucleic acids in plasma by extending the array of PT impregnated membranes incorporated with their corresponding complementary PNAs., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Integrating the concept of biodegradation and light-triggered localized therapy in a functional nanoformulation is the current approach in onco-nanomedicine. Morphology control with an enhanced photothermal response, minimal toxicity, and X-ray attenuation of polymer-based nanoparticles is a critical concern for image-guided photothermal therapy. Herein, we describe the simple design of cost-effective and degradable polycaprolactone-based plasmonic nanoshells for the integrated photothermolysis as well as localized imaging of cancer cells. The gold-deposited polycaprolactone-based plasmonic nanoshells (AuPCL NS) are synthesized in a scalable and facile way under ambient conditions. The synthesized nanoshells are monodisperse, fairly stable, and highly inert even at five times (250 μg/mL) the therapeutic concentration in a week-long test. AuPCL NS are capable of delivering standalone photothermal therapy for the complete ablation of cancer cells without using any anticancerous drugs and causing toxicity. It delivers the same therapeutic efficacy to different cancer cell lines, irrespective of their chemorefractory status and also works as a potential computed tomography contrast agent for the integrated imaging-directed photothermal cancer therapy. High biocompatibility, degradability, and promising photothermal efficacy of AuPCL NS are attractive aspects of this report that could open new horizons of localized plasmonic photothermal therapy for healthcare applications.

Multifunctional biodegradable nanomaterials that could be used for both imaging and therapy are being researched extensively. A simple technique to synthesize multifunctional nanoparticles without compromising on any of their functionality is a challenge. We have attempted to optimize a two-step procedure of gold coated polymeric template involving 1) Single pot synthesis of PLGA nanoparticles with cationic surface charge using glycol chitosan and 2) in situ gold coating for formation of gold coated PLGA nanoshell (AuPLGA-NS). These gold-coated PLGA nanoparticles were explored for photothermal therapy (PTT) and as X-ray/CT contrast agents. Biocompatibility and photothermal cytotoxicity of AuPLGA-NS were evaluated in-vitro and results confirmed the therapeutic efficacy of these particles resulting in 80% cancer cell death. Besides, it also showed potential X-ray/CT imaging ability with contrast equivalent to that of Iodine. The results demonstrated that these gold-coated PLGA nanoparticles synthesized by a simple approach could be used as a multifunctional nanosystem for cancer theranostics., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The unresolved and paramount challenge in bio-imaging and targeted therapy is to clearly define and demarcate the physical margins of tumor tissue. The ability to outline the healthy vital tissues to be carefully navigated with transection while an intraoperative surgery procedure is performed sets up a necessary and under-researched goal. To achieve the aforementioned objectives, there is a need to optimize design considerations in order to not only obtain an effective imaging agent but to also achieve attributes like favorable water solubility, biocompatibility, high molecular brightness, and a tissue specific targeting approach. The emergence of near infra-red fluorescence (NIRF) light for tissue scale imaging owes to the provision of highly specific images of the target organ. The special characteristics of near infra-red window such as minimal auto-fluorescence, low light scattering, and absorption of biomolecules in tissue converge to form an attractive modality for cancer imaging. Imparting molecular fluorescence as an exogenous contrast agent is the most beneficial attribute of NIRF light as a clinical imaging technology. Additionally, many such agents also display therapeutic potentials as photo-thermal agents, thus meeting the dual purpose of imaging and therapy. Here, we primarily discuss molecular imaging and therapeutic potentials of two such classes of materials, i.e., inorganic NIR dyes and metallic gold nanoparticle based materials.