Dipanjan Pan

Two‐dimensional borophene, with its electron‐deficient bonding and structural polymorphism, is an emerging platform for constructing organized nano‐bio interfaces. In this work, we demonstrate molecularly programmed borophene‐DNA nanoarchitectures by interfacing χ ³ ‐phase borophene nanosheets with thiolated, fluorophore‐labeled stem‐loop oligonucleotides. Thermodynamic, spectroscopic, microscopic, and computational analyses reveal two governing interaction modes: a primary boron–sulfur anchoring interaction and a secondary guanine‐mediated surface interaction, which produce vertically and horizontally oriented DNA configurations on borophene. The resulting hybrids display efficient distance‐dependent fluorescence quenching via static nanosurface energy transfer, with a Stern–Volmer constant K _sv = 1.4 × 10 ⁴ M ^{− 1} . Temperature‐dependent quenching and molecular dynamics simulations indicate formation of a stable ground‐state complex and long‐range photophysical coupling between the fluorophore and borophene. This distance‐responsive optical switching supports amplification‐free nucleic acid detection, achieving a detection limit of 37 viral RNA copies µL ^{− 1} for clinical HIV‐1 samples. Molecular dynamics simulations further corroborate the observed configurations and show favorable Gibbs free energies for both stem‐loop‐ and target‐bound states. Overall, borophene emerges as a chemically programmable, photophysically active 2D scaffold for organizing oligonucleotides into functional nanoarchitectures and guiding nano‐enabled optical sensing design.

Spectral photon-counting computed tomography (SPCCT) enables material-resolved imaging through K-edge discrimination, yet its application to multiplexed molecular mapping of human surgical specimens remains underexplored. Here, we report a clinically relevant multiplex K-edge imaging strategy and demonstrate its utility directly in human chronic subdural hematoma (CSDH) membranes. SPCCT-derived human data was obtained by treating patient tissues with a rationally designed and engineered dual K-edge nanopair composed of hafnium oxide (K-edge 65.3 keV) and gold (K-edge 80.3 keV) nanoparticles to simultaneously and ratiometrically map angiogenic (αvβ3) and fibrotic (fibrin) markers in the CSDH microenvironment. This nanopair provides optimized spectral separation necessary for multiplexed molecular phenotyping in human samples with high accuracy. Guided by signal separation physics, the nanopair was designed to minimize energy bin overlaps and maximize the signal-to-noise ratio in quantitative material decomposition maps. Using a calibrated phantom protocol on a Medipix3RX-based SPCCT system, we achieved accurate quantification of both elements at low millimolar concentrations. Surface-engineered hafnium nanoprobes functionalized with cyclic RGD peptides and gold nanoprobes conjugated to antifibrin antibodies enabled target-specific accumulation in distinct pathological microenvironments. Human data was analyzed as three-dimensional multicolor reconstructions that revealed simultaneous, voxel-level mapping of spatially distinct angiogenic and fibrotic microenvironments, which were validated by machine-learning-assisted immunohistochemistry quantification. These findings demonstrate the utility of a nanomaterial-driven, multiplex K-edge imaging framework for volumetric molecular phenotyping of human tissues and advance SPCCT toward quantitative, multicontrast translational imaging.

Borophene (BPH), a monolayer boron allotrope, exhibits outstanding electrical and mechanical properties but remains intrinsically constrained by its excessive susceptibility to oxidative degradation in aqueous and physiological environments. This study demonstrates that protein-assisted exfoliation using human serum albumin (HSA) establishes a dynamic biointerfacial sheath (BIS) that decouples environmental stability from intracellular degradation. HSA forms a robust BIS via multivalent hydrophobic, electrostatic, and thiol-mediated interactions, driving exfoliation into ultrathin nanosheets while suppressing air- and serum-induced oxidation. Proteinized BPH (PBPH) shows enhanced extracellular colloidal and chemical stability; however, upon cellular uptake, the same interface promotes rapid reactive oxygen species-driven degradation, leading to lattice fragmentation, loss of crystallinity, and conversion into soluble boronate species. Multimodal analyses confirm accelerated degradation kinetics and environmental stability of PBPH. These results highlight the protein corona as an active regulator of nanomaterial fate, enabling programmable decoupling of extracellular persistence from intracellular clearance in oxidation-prone two-dimensional systems.

Syphilis diagnosis requires pairing treponemal and non-treponemal antibody results, yet rapid tests combining both markers lose sensitivity at the low RPR titers (≤1:4) most critical in early infection and pregnancy. The limitation lies with the reporter: conventional gold nanoparticles (AuNPs) cannot generate high-contrast signals at low antibody concentrations without exceeding the diameter that allows capillary transport through a nitrocellulose membrane. Here, we report gold–silver–gold (Au–Ag–Au) multilayer plasmonic nanoparticles (ML-PNPs) that exploit interfacial plasmon hybridization to overcome this trade-off. Polyhedral 50–58 nm particles were prepared by seed-mediated growth followed by galvanic replacement, and their layered structure was confirmed by electron microscopy, elemental mapping, and X-ray photoelectron spectroscopy. A silver interlayer between chemically robust gold domains couples across two metal–dielectric interfaces, while the outer gold shell preserves colloidal stability and thiol-based bioconjugation at hydrodynamic diameters below 60 nm. Finite-difference time-domain (FDTD) simulations and hyperspectral imaging showed a broadened, red-shifted resonance (scattering maximum 658 nm vs 555 nm for AuNPs) with 18-fold enhanced absorption. In a dual-marker colorimetric lateral flow immunoassay (CLFIA), ML-PNPs improved the visual detection limit by 3-fold and required 6-fold fewer particles per visible test spot. Across 36 clinical specimens spanning RPR titers of 1:1 to 1:128, treponemal and nontreponemal test-line intensities increased by 19–46%, and low-titer 1:1 samples missed by AuNP strips were reliably detected, with full agreement with reference methods and no cross-reactivity with HIV-1 or HCV sera. Coupled with fingerstick sampling and on-strip plasma separation, this supports same-visit execution of the reverse testing algorithm in an instrument-free format.

Paper-based diagnostics such as lateral flow assays (LFAs) and microfluidic paper-based analytical devices (µPADs) have attracted considerable attention because of their low cost, portability, and ease of use. Currently, to enable fabrication of µPADs and improve LFA performance, hydrophobic blocks are patterned on paper substrates. However, fabrication of high-resolution hydrophobic barriers remains a major challenge. In this work, we developed a novel silicone extrudable ink for the fabrication of hydrophobic features on paper substrates. The ink was formulated using a vinyl-terminated polydimethylsiloxane (vPDMS) and polymethylhydrosiloxane (PMHS) system crosslinked through platinum-catalyzed hydrosilylation, and its rheological properties were tailored by incorporating silica fillers, obtaining a shear-thinning gel suitable for extrusion. The resulting formulation provided tunable properties, controlled deposition, and stable feature formation, enabling simple, low-cost, rapid, and robust fabrication of high-resolution hydrophobic barriers. Using this approach, we demonstrated improved fluid confinement and pattern fidelity on paper substrates, fabricated high-resolution paper microfluidic devices down to 150 µm channel width, and enhanced the sensitivity of an LFA for a malaria diagnostic test. These results highlight the potential of this silicone ink platform as a practical and scalable strategy for advancing high-performance paper-based diagnostic technologies.

Emerging nanomedicine strategies have established clinical translation and the ability to offset conventional therapeutic challenges. This study aimed to report the development and analysis of a nanoscale material that functioned as both a high-Z radiosensitizer and a prodrug delivery system. In this study, a nanoscale platform using two complementary radiosensitizing mechanisms was designed and developed to overcome nonspecific toxicity, which is a challenge in both chemotherapy and radiotherapy. High-Z physical radiosensitization was coupled with the inhibition of a critical DNA double-strand break repair mechanism, homologous recombination, through a lipid nanoparticle decorated with ultrasmall Hafnia nanoparticles and loaded with an amphiphilic prodrug. In vitro and in vivo studies demonstrated significant enhancement of therapeutic effects, cell killing, or tumor regression, respectively, versus radiation alone. These results support the use of this combination system as a practical strategy for maintaining treatment efficacy at modest doses of radiation and offset associated adverse effects.