Avijit Ghosh

Bio: Avijit Ghosh is an academic researcher from University of Calcutta. The author has contributed to research in topics: Population & Rhodamine. The author has an hindex of 12, co-authored 40 publications receiving 349 citations. Previous affiliations of Avijit Ghosh include Zoological Survey of India.

Delivery of Dual miRNA Through CD44-targeted Mesoporous Silica Nanoparticles for Enhanced and Effective Triple-Negative Breast Cancer Therapy

Abstract: The development of new therapeutic strategies to target triple-negative breast cancer (TNBC) is in much demand to overcome the roadblocks associated with the existing treatment procedures. In this regard, therapies targeting the CD44 receptor have drawn attention for more than a decade. MicroRNAs (miRNAs) modulate post-transcriptional gene regulation and thus, the correction of specific miRNA alterations using miRNA mimics or antagomiRs is an emerging strategy to normalize the genetic regulation in the tumor microenvironment. It has been acknowledged that miR-34a is downregulated and miR-10b is upregulated in TNBC, which promotes tumorigenesis and metastatic dissemination. However, there are a few barriers related to miRNA delivery. Herein, we have introduced tailored mesoporous silica nanoparticles (MSNs) for the co-delivery of miR-34a-mimic and antisense-miR-10b. MSN was functionalized with a cationic basic side chain and then loaded with the dual combination to overexpress miR-34a and downregulate miR-10b simultaneously. Finally, the loaded MSNs were coated with an hyaluronic acid-appended PEG-PLGA polymer for specific targeting. The cellular uptake, release profile, and subsequent effect in TNBC cells were evaluated. In vitro and in vivo studies demonstrated high specificity in TNBC tumor targeting, leading to efficient tumor growth inhibition as well as the retardation of metastasis, which affirmed the clinical application potential of the system.

Strategically Modified Rhodamine–Quinoline Conjugate as a CHEF-Assisted FRET Probe for Au3+: DFT and Living Cell Imaging Studies

Abstract: A systematic journey from O-donor through S-donor to N-donor chelator led to the development of a highly selective Au3+ chemosensor that operates via a CHEF-induced FRET mechanism. This sensing protocol avoids unwanted possible side reactions observed in alkyne-based gold sensors. DFT studies strongly support the experimental facts. The probe RT-2 detects Au3+ in the presence of the masking agent KI to minimize Hg2+ interference; however, RQ-2 selectively detects Au3+ without any interference and shows reversibility in the sensing in the presence of tetrabutylammonium cyanide. The probe efficiently images Au3+ in living HeLa cells under a fluorescence microscope.

Transferrin-decorated thymoquinone-loaded PEG-PLGA nanoparticles exhibit anticarcinogenic effect in non-small cell lung carcinoma via the modulation of miR-34a and miR-16

Abstract: Non-small cell lung carcinoma (NSCLC) is a highly lethal type of cancer with limited therapeutic avenues available to date. In the present study, we formulated PEGylated PLGA thymoquinone nanoparticles (TQ-Np) for improved TQ delivery to NSCLC cells. Transferrin (TF), a biodegradable, non-immunogenic and non-toxic protein, is well known to bind to TFR (transferrin receptor) over-expressed in non-small cell lung carcinoma A549 cells. Thus, the further decoration of the PEGylated PLGA thymoquinone nanoparticles with transferrin (TF-TQ-Np) enhanced the internalization of the nanoparticles within the A549 cells and the activity of TQ. We established TF-TQ-Np as a potent anti-tumorigenic agent through the involvement of p53 and the ROS feedback loop in regulating the microRNA (miRNA) circuitry to control apoptosis and migration of NSCLC cells. TF-TQ-Np-mediated p53 up-regulation favored the potential simultaneous activation of miR-34a and miR-16 targeting Bcl2 to induce apoptosis in the A549 cells. Additionally, TF-TQ-Np also restricted the migration through actin de-polymerization via activation of the p53/miR-34a axis. Further studies in chick CAM xenograft models confirmed the anti-cancer activity of TF-TQ-Np by controlling the p53/miR-34a/miR-16 axis. Furthermore, in vivo experiments conducted in a xenograft model in immunosuppressed Balb/c mice also proved the efficacy of the nanoparticles as an antitumor agent against NSCLC. Thus, our findings cumulatively suggest that the transferrin-adorned TQ-Np successfully coupled two distinct miRNA pathways to potentiate the apoptotic death cascade in the very lethal NSCLC cells and also restricts the migration of these cells without imparting any significant toxicity, which occurs in the widely used chemotherapeutic combinations. Thereby, our findings rekindle new hopes for the development of improved targeted therapeutic options with specified molecular objectives for combating the deadly NSCLC.

Carbon-Dot and Quantum-Dot-Coated Dual-Emission Core–Satellite Silica Nanoparticles for Ratiometric Intracellular Cu2+ Imaging

Abstract: Copper (Cu2+) is physiologically essential, but excessive Cu2+ may cause potential risk to plants and animals due to the bioaccumulative properties. Hence, sensitive recognition is crucial to avoid overintake of Cu2+, and visual recognition is more favored for practical application. In this work, a dual-emission ratiometric fluorescent nanoprobe was developed possessing the required intensity ratio, which can facilitate the sensitive identification of Cu2+ by the naked eye. The probe hybridizes two fluorescence nanodots (quantum dots (QDs) and carbon dots (CDs)). Although both of them can be viable fluorescence probes for metal ion detection, rarely research has coupled this two different kinds of fluorescence material in one nanosensor to fabricate a selectively ratiometric fluorescence probe for intracellular imaging. The red emitting CdTe/CdS QDs were capped around the silica microsphere to serve as the response signal label, and the blue-emitting CDs, which is insensitive to the analyte, were covalent...

A New Strategy: Distinguishable Multi-substance Detection, Multiple Pathway Tracing Based on a New Site Constructed by the Reaction Process and Its Tumor Targeting

Abstract: In recent years, it has become a trend to employ organic molecular fluorescent probes with multireaction sites for the distinguishable detection and biological imaging of similar substances. However, the introduction of multireaction sites brought great challenges to organic synthesis, and at the same time, often destroyed the conjugated structure of the molecules, leading to an unsatisfactory fluorescence emission wavelength not conducive to practical application. As the eternal theme of life, metabolism goes on all the time. Metabolism is a series of ordered chemical reactions that occurs in the organism to maintain life. Chemical reactions in metabolism can be summarized as metabolic pathways. Simultaneous monitoring of different metabolic pathways of the same substance poses a lofty challenge to the probe. Here, we developed a new strategy: to construct new sites through the preliminary reactions between probes and some targets, which can be used to further distinguish among targets or detect their metabolites, so as to realize the simultaneous visualization tracer of multiple metabolic pathways. By intravenous injection, it revealed that the probe containing benzopyrylium ion can target tumors efficiently, and thiols are highly expressed in tumors compared to other tissues (heart, lung, kidney, liver, etc.). The consumption of thiols by the probe could not prevent tumor growth, suggesting that the tumor cure was not correlated with thiol concentration. The construction of new sites in the reaction process is a novel idea in the pursuit of multiple reaction sites, which will provide more effective tools for solving practical problems.

Lignin-Based Nanoparticles Stabilized Pickering Emulsion for Stability Improvement and Thermal-Controlled Release of trans-Resveratrol

Abstract: In this work, we designed a novel multifunctional Pickering emulsion stabilized by lignin-based nanoparticles. We utilized the industrial waste lignin to prepare thermoresponsive lignin copolymer by grafting poly(N-isopropylacrylamide) (PNIPAM) onto lignin via atom transfer radical polymerization (ATRP) and then formed self-assembled nanoparticles (AL-g-PNIPAM NPs). AL-g-PNIPAM NPs well stabilized trans-resveratrol (trans-RSV)-containing palm oil emulsion droplets in water. Thanks to the abundant UV chromophoric groups of lignin, the light stability of trans-RSV was significantly improved by the protecting of the AL-g-PNIPAM NPs layer. Moreover, the emulsion properties and release behavior strongly depend on the temperature and nanoparticles size: decreasing temperature induced deformation of AL-g-PNIPAM NPs at the interface, an increase in droplet size, and the accelerated release of trans-RSV. These results showed the great potential of this approach of a green functional lignin-based nanoparticles stab...