Biology subjects

Bhatia, D.

Publications and source records attributed to Bhatia, D..

13 recordsLinked to original sources

bioRxiv2026

Bioactive Spermidine-Crosslinked DNA Hydrogel for rapid homeostasis and accelerated wound healing

Damage to the skin by trauma, burns, or surgical procedures often results in uncontrolled bleeding, which remains a leading cause of preventable death following injury, yet most conventional hemostatic materials are engineered solely to arrest bleeding and often adhere strongly to the wound bed, causing pain, rebleeding, and disruption of newly formed tissue upon removal. Here, we report a DNA hydrogel that structurally mimics neutrophil extracellular traps (NETs) and is crosslinked using a bioactive small molecule with potent autophagy-inducing, cardioprotective, anti-inflammatory, antioxidant, and mitochondria-protective properties, integrating rapid hemostasis with active support for tissue regeneration in a single biomaterial. The DNA network provides an intrinsically biocompatible, biodegradable scaffold capable of recruiting platelets and erythrocytes to achieve rapid clot formation, while the bioactive crosslinker is released as the network degrades, delivering a sustained cytoprotective and anti-inflammatory stimulus directly at the wound site. The hydrogel was characterised physiochemically and evaluated for cytocompatibility, hemolytic potential, hemostatic efficacy, and wound-healing performance in a murine model. Results demonstrate that the bioactive-crosslinked DNA hydrogel achieves rapid, effective hemostasis, while accelerating wound closure and supporting regenerative tissue remodelling. This dual-function platform offers a promising strategy for next-generation wound-care biomaterials that unite immediate bleeding control with accelerated, natural tissue healing.

bioengineering↗

bioRxiv2026

Green Solvothermal Synthesis of Nitrogen-Doped Chamomile-Derived Carbon Dots with Superior Quantum Yield and Bioimaging Potential: A Comparative Physicochemical Evaluation

Conventional fluorescent imaging probes, including organic dyes and semiconductor quantum dots, suffer from inherent limitations such as photobleaching, cytotoxicity, poor aqueous dispersibility, and complex synthetic routes, necessitating the development of next-generation nanoscale fluorophores suitable for biological imaging. Carbon dots (CDs) have emerged as a compelling alternative owing to their nanoscale dimensions, tunable photoluminescence, excellent biocompatibility, and amenability to green synthesis from biomass-derived precursors. Herein, we report a comparative synthesis and systematic physicochemical evaluation of nitrogen-doped and undoped carbon dots derived from chamomile (Matricaria chamomilla L.) extract, prepared via solvothermal and microwave-assisted routes. Among the four synthesized variants--CM ST-U, CM ST-N, CM MW-U, and CM MW-N--the solvothermally synthesized nitrogen-doped carbon dots (CM ST-N) exhibited markedly superior optical performance, characterized by a high fluorescence quantum yield of 57.2%, which is among the highest reported for biomass-derived nitrogen-doped carbon dots. Comprehensive characterization using UV-visible spectroscopy, photoluminescence (PL) spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), dynamic light scattering (DLS), zeta potential analysis, and atomic force microscopy (AFM) confirmed the nanoscale dimensions (~8.3 nm), surface-rich functional groups, successful nitrogen incorporation (10.86 %), and moderate colloidal stability (zeta potential: -17.3 mV). Photoluminescence stability studies across seven solvent systems including biologically relevant media--phosphate-buffered saline (PBS), Dulbeccos modified Eagles medium (DMEM), and serum-free medium (SFM) demonstrated sustained fluorescence emission over 72 hours. In vitro cytotoxicity assessment using the MTT assay on RPE-1 retinal pigment epithelial cells confirmed high cell viability (>70%) across a broad concentration range (10-500 {micro}g mL-1) over multiple exposure durations. Collectively, these results establish CM ST-N as a highly fluorescent, biocompatible, and colloidally stable nanoprobe with strong potential for fluorescence-based bioimaging applications.

bioengineering↗

bioRxiv2025

Growth-factor ligand functionalization enhances cellular and in vivo uptake of DNA nanodevices

Epidermal Growth Factor (EGF) and Transforming Growth Factor beta (TGF-{beta}) are two important classes of growth factor that regulates cell growth, cell proliferation, differentiation, immune responses, and extracellular matrix generation. Using a short peptide-based ligand coupled to DNA nanocages, we present the enhanced internalization of a receptor-mediated peptide-DNA nanocage. We used here tdDNA as a delivery vehicle. Our study in cellular and in vivo showed excellent internalization, cell growth, and inhibition. We expect that a tdDNA-modified receptor-binding peptides could become a valuable scaffold for use as a cellular programming and regenerative material.

bioengineering↗

bioRxiv2025

DNA cross-over motifs based, programmable supramolecular hydrogels for mechanoregulatory effects of cellular behaviour and cytoskeleton reorganization

The development of mechanically tunable DNA-based supramolecular hydrogels that recapitulate the dynamic mechanoelastic properties of native extracellular matrices (ECMs) is critical for advancing 3D tissue engineering. DNA supramolecular hydrogels with their precise programmable architecture and impeccable control at the nanometre scale assembly make them a highly lucrative biopolymer in the design of ECM-mimicking scaffolds. This study explores the fabrication of stiffness-customizable rigid DNA hydrogels with varying branching architectures, including Double Crossovers (DX), Paranemic Crossovers (PX), and Tensegrity motif structures with three to six arms. Our study reveals that by incorporating different numbers of crossovers, branching arms, and the type of sticky-armed linkers, it is possible to generate a range of DNA hydrogels with varying network geometry and mechanoelastic properties ranging from 50-300 kPa, without any chemical / enzymatic crosslinking aid. These DNA hydrogels mechanoregulate cellular behaviour in retinal pigment epithelial (RPE1) cells by enhancing cellular adhesion, elongation (3 - 8x area increase vs. control), viability (concentration-dependent, 1 - 8x vs. control), organellar homeostasis, including mitochondrial fragmentation and ER stress attenuation. This work establishes a framework for automating DNA hydrogel-based scaffold fabrication processes to meet the preferences of various cells/tissues with bespoke mechanical cues, advancing personalized high-throughput tissue engineering platforms. Graphical abstract

bioengineering↗

bioRxiv2024

Enzyme-Regulated Non-Thermal Fluctuations Enhance Ligand Diffusion and Receptor-Mediated Endocytosis

Active enzymes during catalyzing chemical reactions, have been found to generate significant mechanical fluctuations, which can influence the dynamics of their surroundings. These phenomena open new avenues for controlling mass transport in complex and dynamically inhomogeneous environments through localized chemical reactions. To explore this potential, we studied the uptake of transferrin molecules in retinal pigment epithelium (RPE) cells via clathrin-mediated endocytosis. In the presence of enzyme catalysis in the extracellular matrix, we observed a significant enhancement in the transport of fluorophore-tagged transferrin inside the cells. Fluorescence correlation spectroscopy measurements showed substantial increase in transferrin diffusion in the presence of active fluctuations. This study sheds light on the possibility that enzyme-substrate reactions within the extracellular matrix may induce long-range mechanical influences, facilitating targeted material delivery within intracellular milieu more efficiently than passive diffusion. These insights are expected to contribute to the development of better therapeutic strategies by overcoming limitations imposed by slow molecular diffusion under complex environments.

biophysics↗

bioRxiv2024

Novel carbon nanoparticles (CNPs) from Catharanthus roseus petals for metal ion sensing and root growth modulation

Nanoparticles are of major interest nowadays due to their distinctive properties. In this study, we present a microwave-assisted green synthesis of carbon nanoparticles from the Catharanthus roseus petals. The nanoparticles exhibited a fluorescence emission in the 300 to 400 nm wavelength region and emitted a characteristic blue fluorescence. The extensive characterization using Bio-AFM showed that the size of nanoparticles was 25.38 nm. M-XRD and Zeta potential analysis confirmed that the nanoparticles were amorphous and exhibited a negative surface charge. The surface functional groups on the nanoparticles were highlighted by FTIR analysis. Metal sensing affinity of the synthesized CNPs and their effect on the plant growth was tested. These CNPs demonstrated the effective sequestration of metallic ions such as copper (Cu2+), iron (Fe2+), and nickel (Ni2+), indicating their potential to be used as biosensors in metal detection. It was found that the effect was proportionate to the Catharanthus roseus petal nanoparticles (CRPNP) concentration, where it exhibits a great affinity for Fe2+. The effect of the nanoparticles analyzed on the root growth of Arabidopsis thaliana showed that CRPNP suppresses the primary root and lateral root numbers. These results demonstrate the use of C. roseus synthesized CNPs in sustainable agriculture by targeting nutrient delivery.

developmental biology↗

bioRxiv2024

Synergistic Modulation of Macrophages by Methotrexate and RELA siRNA Folate-Liposome: A Precision Therapy to Prevent Joint Degradation in Collagen-Induced Arthritic Rats

Rheumatoid arthritis (RA) is a chronic autoimmune disorder characterized by inflammation and joint destruction. Current treatments, such as Methotrexate (MTX), while effective, often have therapeutic limitations like high plasma Cmax and lack of sustained release. This study explores a synergistic approach to RA therapy using folate-liposomal co-delivery of MTX and RELA siRNA, aimed at RAW264.7 macrophage repolarization through inhibition of the NF-{kappa}B pathway. Extensive invitro characterizations demonstrate the stability and biocompatibility of this combinatorial therapy in folate-liposomes. In collagen-induced arthritis (CIA) rat model, we observed a reduction in synovial inflammation and improved mobility following treatment. The combined MTX and RELA siRNA approach indirectly inhibits inflammatory cytokines and other biochemical parameters such as Rheumatoid factor (RF) and C-reactive protein (CRP). The targeted macrophage delivery yields a marked therapeutic effect in RAW264.7 murine macrophages, potentially modulating the M1 to M2 macrophage polarization. Overall, this research presents a promising avenue for innovative therapies in RA management by inhibiting the inflammatory cascade and preventing joint damage.

pharmacology and toxicology↗

bioRxiv2023

Novel carbon nanoparticles derived from Bougainvillea modulate vegetative growth in Arabidopsis

We present a green synthesis method of producing blue fluorescence emitting carbon nanoparticles (CNPs) through a simple and cost-effective single-step hydrothermal reaction. The synthesis utilized bract extracts and pollen grains from three Bougainvillea species: B. spectabilis, B. alba, and B. buttiana. The CNPs exhibited photoluminescence, with the highest emission observed in the ultraviolet region. Atomic force microscopy analysis revealed that the size of synthesized CNPs ranged from 23 nm to 83 nm. Fourier transform infrared analysis provided a comprehensive understanding of the CNPs surface functional groups, with carbon being the predominant group. X-ray diffraction analysis confirmed the amorphous nature of the synthesized CNPs. Zeta potential measurements indicated that the particles carried a negative charge, suggesting their colloidal stability. In experiments conducted with Arabidopsis thaliana seedlings, CNPs derived from B. alba pollen grains were found to promote leaf area expansion while simultaneously inhibiting primary root growth. Conversely, other CNPs demonstrated detrimental effects on vegetative growth. These findings underscore the potential application of these novel CNPs in agriculture.

plant biology↗

bioRxiv2023

Dopamine functionalized, red carbon quantum dots for in vivo bioimaging, cancer therapeutics, and neuronal differentiation

One of the crucial requirements of quantum dots for biological applications is their surface modifications for very specific and enhanced biological recognition and uptake. Toward this, we present the green synthesis of bright, red-emitting carbon quantum dots derived from mango leaf extract (mQDs). These mQDs are conjugated electrostatically with dopamine to form mQDs-dopamine (mQDs: DOPA) bioconjugates. Bright red fluorescence of mQDs was used for bioimaging and uptake in multiple cell lines, tissues, and in vivo models like zebrafish. mQDs exhibited the highest uptake in brain tissue as compared to others. mQD:DOPA conjugate induced cellular toxicity only in cancer cells while showing increased uptake in epithelial cells and zebrafish. Additionally, the mQDs: DOPA promoted neuronal differentiation of SH-SY5Y cells to complete neurons. Both mQDs and mQDs: DOPA exhibited potential for higher collective cell migrations implicating their future potential as next-generation tools for advanced biological and biomedical applications. TOCmQDs were electrostatically conjugated with dopamine (DOPA) to form the mQDs: DOPA bioconjugate. mQDs are used to image cells, tissues, and zebrafish embryos. mQDs: DOPA kills cancer cells, differentiates neuronal cells, and increases the uptake of mQDs in zebrafish embryos. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=116 SRC="FIGDIR/small/545347v1_ufig1.gif" ALT="Figure 1"> View larger version (25K): org.highwire.dtl.DTLVardef@f521a4org.highwire.dtl.DTLVardef@173a8f0org.highwire.dtl.DTLVardef@585271org.highwire.dtl.DTLVardef@8c959d_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

bioRxiv2023

Lipid modification of DNA nanocages enhances cellular uptake, migration, and in vivo uptake

The extraordinary self-assembling nature of DNA nanostructures and high functionality enables the formulation of DNA nanostructures with multiple chemical and biological molecules. How the whole organisms in native as well as modified; and how stable they are inside take up exactly these modified DNA nanostructures the organisms still remains to be explored. Here we report the fabrication and evaluation of a new conjugate of a cationic lipid, N-[one-(two, 3-dioleyloxy) propyl]-N, N, N-trimethylammonium chloride (DOTMA) and DNA tetrahedron nanostructure (TdN) for the enhanced uptake, stability, bioimaging, and biotherapeutics in cells and zebrafish (Danio rerio) eleuthero embryos as a model organism. We summarise the enhanced uptake potential of TdN-DOTMA conjugate for futuristic biomedical applications such as drug delivery, bioimaging, biosensing, and therapeutics.

bioengineering↗

bioRxiv2021

Ultrasound exposure enhances cellular uptake of nanoscale cargos

DNA nanotechnology utilizes DNA as a structural molecule to design palette of nanostructures with different shapes and sizes. DNA nanocages have demonstrated significant potential for drug delivery. Therefore, enhancing the delivery of DNA nanocages into cells can improve their efficacy as drug delivery agents. Numerous studies have reported the effects of ultrasound for enhancing drug delivery across biological barriers. The mechanical bioeffects caused by cell-ultrasound interaction can cause sonoporation, leading to enhanced uptake of drugs, nanoparticles, and chemotherapeutic agents through membranes. Whether ultrasound exposure can enhance the delivery of DNA nanocages has not been explored, which is the focus of this study. Specifically, we investigated the effects of ultrasound on the cellular uptake of propidium Iodide, fluorescent dextrans, and DNA nanostructures). We provide evidence of modulation of pore formation in the cell membrane by ultrasound by studying the intracellular uptake of the impermeable dye, propidium iodide. Treatment of cells with low amplitudes of ultrasound enhanced the uptake of different sizes of dextrans and DNA based nanodevices. These findings could serve as the foundation for further development ultrasound-enabled DNA nanostructure delivery and for specific understanding of underlying biological mechanisms of interaction between ultrasound parameters and cellular components; the knowledge that can be further explored for potential biological and biomedical applications.

bioengineering↗

bioRxiv2018

International travelers and genomics uncover a ‘hidden’ Zika outbreak

The ongoing Zika epidemic in the Americas has challenged public health surveillance, response, and control systems. Even as the epidemic appears to be near its end in the Americas, it is unclear whether substantial Zika virus transmission may still be ongoing. This issue is exacerbated by large discrepancies in local case reporting and significant delays in detecting outbreaks due to surveillance gaps. To uncover locations with lingering outbreaks in the Americas, we investigated travel-associated Zika cases diagnosed in the United States and Europe to identify signatures of transmission dynamics that were not captured by local reporting. We found that a large and unreported Zika outbreak occurred in Cuba during 2017, a year after peak transmission in neighboring countries, with cases still appearing in 2018. By sequencing Zika virus from infected travelers, we show that the 2017 outbreak in Cuba was sparked by long-lived lineages of Zika virus introduced from multiple places in the Americas a year prior. Our data suggest that while aggressive mosquito control in Cuba may initially have been effective at mitigating Zika virus transmission, in the absence of vaccines, herd immunity, or strong international coordination, such control measures may need to be maintained to be effective. Our study highlights how Zika virus may still be silently spreading in the Americas and provides a framework for more accurately understanding outbreak dynamics.

epidemiology↗

bioRxiv2018

Projecting the end of the Zika virus epidemic in Latin America: a modelling analysis

Background Zika virus (ZIKV) emerged in Latin America & the Caribbean (LAC) region in 2013, and has had serious implications for population health in the region. In 2016, the World Health Organization declared the ZIKV outbreak a Public Health Emergency of International Concern following a cluster of associated neurological disorders and neonatal malformations. In 2017, Zika cases declined, but future incidence in LAC remains uncertain due to gaps in our understanding, considerable variation in surveillance and a lack of a comprehensive collation of data from affected countries.\n\nMethods Our analysis combines information on confirmed and suspected Zika cases across LAC countries and a spatio-temporal dynamic transmission model for ZIKV infection to determine key transmission parameters and projected incidence in 91 major cities within 35 countries. Seasonality was determined by spatio-temporal estimates of Aedes aegypti vector capacity. We used country and state-level data from 2015 to mid-2017 to infer key model parameters, country-specific disease reporting rates, and the 2018 projected incidence. A 10-fold cross-validation approach was used to validate parameter estimates to out-of-sample epidemic trajectories.\n\nResults There was limited transmission in 2015, but in 2016 and 2017 there was sufficient opportunity for wide-spread ZIKV transmission in most cities, resulting in the depletion of susceptible individuals. We predict that the highest number of cases in 2018 within some Brazilian States (Sao Paulo and Rio de Janeiro), Colombia and French Guiana, but the estimated number of cases were no more than a few hundred. Model estimates of the timing of the peak in incidence were correlated (p<0.05) with the reported peak in incidence. The reporting rate varied across countries, with lower reporting rates for those with only confirmed cases compared to those who reported both confirmed and suspected cases.\n\nConclusions The findings suggest that the ZIKV epidemic is by and large over, with incidence projected to be low in most cities in LAC in 2018. Local low levels of transmission are probable but the estimated rate of infection suggests that most cities have a population with high levels of herd immunity.

epidemiology↗