@article{shukla_joshi_kadian_narayan_2024, title={Development of Drug-Loaded PCL@MOF Film Enclosed in a Photo Polymeric Container for Sustained Release}, url={http://dx.doi.org/10.1021/acsabm.4c00564}, DOI={10.1021/acsabm.4c00564}, abstractNote={The programmed fabrication of oral dosage forms is associated with several challenges such as controlled loading and disintegration. To optimize the drug payload, excipient breakdown, and site-specific sustained release of hydrophobic drug (sulfamethoxazole, SM), we propose the development of acrylate polymer tablets enclosed with drug-loaded polycaprolactone (PCL) films. The active pharmaceutical ingredient (API) is physisorbed into the porous iron (Fe)-based metal-organic framework (MOF) and later converted to tangible PCL films, which, upon folding, are incorporated into the acrylate polymer matrices (P1/P2/P3). X-ray powder diffraction (XRPD) analysis and scanning electron microscopy (SEM) micrographs confirmed the stability and homogeneous distribution of MOF within the 50 μm thick film. Adsorption-desorption measurements at ambient temperatures confirmed the decrease in the BET surface area of PCL films by 40%, which was ∼3.01 m/g, and pore volume from 30 to 9 nm. The decrease in adsorption and surface parameters could confirm the gradual accessibility of SM molecules once exposed to a degrading environment. Fourier transform infrared (FTIR) analyses of in vitro dissolution confirmed the presence of the drug in the MOF-PCL film-enclosed tablets and concluded the cumulative SM release at pH ∼ 8.2 which followed the order SM@Fe-MOF < P1/P2/P3 < PCL-SM@Fe-MOF < P1/PCL-SM@Fe-MOF < P3/PCL-SM@Fe-MOF. The results of the study indicate that the P3/PCL-SM@Fe-MOF assembly has potential use as a biomedical drug delivery alternative carrier for effective drug loading and stimuli-responsive flexible release to attain high bioavailability.}, journal={ACS Applied Bio Materials}, publisher={ACS Applied Bio Materials}, author={Shukla, Shubhangi and Joshi, Naveen Narasimhachar and Kadian, Sachin and Narayan, Roger}, year={2024}, month={Jul} }
 @inbook{patil_sharath_halse_saraswathi_murgunde_joshi_kalasad_2024, title={Elemental semiconductor nanocrystals}, url={http://dx.doi.org/10.1016/b978-0-323-96125-7.00025-3}, DOI={10.1016/b978-0-323-96125-7.00025-3}, abstractNote={Semiconductor nanocrystals are one of the most studied nanoscale materials during the last three decades due to their size-dependent physical and chemical properties. These semiconductor nanocrystals are a unique collection of materials that have narrow excitation bands, size tunable, high quantum yield, broad absorption profiles, photochemical stability, and symmetric emission spectra. In this chapter, a review on basics of semiconductor nanocrystals, size and surface effects, quantum dots, and different elemental semiconductor nanocrystals is provided. The detailed illustration about fundamental properties, synthesis, functionalization, controlling different size and shape with various applications of elemental semiconductor nanocrystals is provided.}, booktitle={Handbook of Emerging Materials for Sustainable Energy}, publisher={Elsevier}, author={Patil, Vismitha S. and Sharath, S.C. and Halse, S.V. and Saraswathi, B. and Murgunde, B.K. and Joshi, Naveen N. and Kalasad, M.N.}, year={2024}, month={Jan}, pages={825–851} }
 @article{joshi_narayan_narayan_2024, title={Multifunctional carbon-based nanostructures (CBNs) for advanced biomedical applications - a perspective and review}, volume={10}, ISSN={["2633-5409"]}, url={https://doi.org/10.1039/D3MA00636K}, DOI={10.1039/D3MA00636K}, abstractNote={Carbon-based nanostructures (CBNs) have attracted immense attention from biomedical researchers due to their unique combination of extraordinary mechanical, thermal, electrical, and optical properties.}, journal={MATERIALS ADVANCES}, author={Joshi, Naveen Narasimhachar and Narayan, Jagdish and Narayan, Roger}, year={2024}, month={Oct} }
 @article{shukla_khanna_sahoo_joshi_narayan_2024, title={Nanomaterial-Coated Carbon-Fiber-Based Multicontact Array Sensors for In Vitro Monitoring of Serotonin Levels}, volume={7}, ISSN={["2576-6422"]}, url={http://dx.doi.org/10.1021/acsabm.3c01089}, DOI={10.1021/acsabm.3c01089}, abstractNote={In this study, we demonstrated the fabrication of multicontact hierarchical probes for the in vitro detection of serotonin levels. The basic three-dimensional (3D) bendable prototypes with 3 (C1), 6 (C2), or 9 (C3) contact surfaces were printed from polymeric resin via the digital light processing (DLP) technique. We chose ultrasonicated carbon fiber strands to transform these designs into multicontact carbon fiber electrodes (MCCFEs). The exposed carbon fiber (CF) surfaces were modified with aminopropyl alkoxysilane (APTMS), followed by the subsequent loading of palladium nanoclusters (PdNPs) to build active recording sites. CF functionalization with PdNPs was achieved by the wet chemical reduction of Pd(II) to Pd(0). The MCCFE configurations demonstrated an enhancement in the electroactive surface area and an improved voltammetric response toward 5-HT oxidation by increasing the points of the contacts (i.e., from C1 to C3). These MCCFEs are comparable to 3D-protruding electrodes as they can enable multipoint analyte detection. Along with the electrode patterns, morphological irregularities associated with both Pd-doped and undoped CFs supported the creation of proximal diffusion layers for facile mass transfer. Low detection limits of 0.8-10 nM over a wide concentration range, from 0.005 nM to 1 mM, were demonstrated. The MCCFE sensors had a relatively low standard deviation value of ∼2%. This type of sensitive and cost-effective electrochemical sensor may prove useful for collecting electrical impulses and long-term monitoring of 5-HT in vivo in addition to in vitro testing.}, number={1}, journal={ACS APPLIED BIO MATERIALS}, author={Shukla, Shubhangi and Khanna, Sumeer and Sahoo, Siba and Joshi, Naveen and Narayan, Roger}, year={2024}, month={Jan}, pages={472–484} }
 @article{joshi_shivashankar_2024, title={Novel synthesis and magnetic evaluation of carbonaceous cobalt spinel ferrite nanostructures}, volume={9}, ISSN={["2059-8521"]}, url={https://doi.org/10.1557/s43580-024-00943-9}, DOI={10.1557/s43580-024-00943-9}, journal={MRS ADVANCES}, author={Joshi, Naveen Narasimhachar and Shivashankar, S. A.}, year={2024}, month={Sep} }
 @article{joshi_shukla_khosla_vanderwal_stafslien_narayan_narayan_2024, title={Q-carbon as an emergent surface coating material for antimicrobial applications}, volume={791}, ISSN={["1879-2731"]}, url={https://doi.org/10.1016/j.tsf.2024.140227}, DOI={10.1016/j.tsf.2024.140227}, abstractNote={Q-carbon, an allotrope of carbon, exhibits exciting functional properties and robust mechanical strength. We propose that the surface of the Q-carbon can be functionalized by doping it with silicon to enhance its performance as a potential implant material. As such, a coating of silicon-doped Q-carbon (Si-Q-carbon) is shown to minimize the formation of biofilm, thus reducing the risk of microbial infection. We report the formation of Si-Q-carbon coatings of varied thicknesses (10nm and 20nm) through the plasma-enhanced chemical vapor deposition technique. The surface composition and the bonding characteristics of the thin films were evaluated by Raman spectroscopy, XPS, and EELS studies, which showed that the thinnest sample (10nm) has a high sp3 content of ∼85%. Furthermore, wettability and surface energy calculations were undertaken to investigate the surface characteristics of the coatings. The 10nm sample was found to be more hydrophilic with a water contact angle of 75.3° (± 0.6°). The antibacterial activity of Si-Q-carbon coatings was investigated using a Staphylococcus epidermidis agar plating technique, and the adhesion of bacteria was explained in terms of the surface properties of the thin films. We demonstrate that the Si-Q-carbon coating with the highest sp3 content is hydrophilic and showed a 57% reduction in adhered biofilm relative to a glass control. We envisage the potential application of Q-carbon in arthroplasty devices with enhanced mechanical strength and resistance to periprosthetic joint infections.}, journal={THIN SOLID FILMS}, author={Joshi, Naveen and Shukla, Shubhangi and Khosla, Nayna and Vanderwal, Lyndsi and Stafslien, Shane and Narayan, Jagdish and Narayan, Roger J.}, year={2024}, month={Feb} }
 @article{joshi_machekposhti_narayan_2023, title={Evolution of Transdermal Drug Delivery Devices and Novel Microneedle Technologies: A Historical Perspective and Review}, volume={3}, url={https://doi.org/10.1016/j.xjidi.2023.100225}, DOI={10.1016/j.xjidi.2023.100225}, abstractNote={The history of transdermal drug delivery is as old as humankind. Transdermal drug delivery has undergone three generations of development; the third generation has involved the use of medical devices and instruments. This review provides a historical perspective on the primary approaches employed in the three generations of transdermal drug delivery. In addition, we explore some of the recently developed transdermal techniques that are deemed promising in the field of drug delivery. We discuss how advances in these techniques have led to devices for the delivery of a therapeutically effective amount of drug across human skin and highlight the limitations of the first- and second-generation drug delivery tools. As such, a review of the performance of these techniques and the toxicity of the devices used in transdermal drug delivery are considered. In the last section of the review, a discussion of the fabrication and operation of different types of microneedles is presented. The applications of microneedles in the sensing and delivery of various therapeutic agents are described in detail. Furthermore, an overview of the efficacy of microneedles as emerging tools for the controlled release of drugs is presented.}, number={6}, journal={JID Innovations}, author={Joshi, Naveen and Machekposhti, Sina Azizi and Narayan, Roger J.}, year={2023}, month={Nov} }
 @article{shukla_machekposhti_joshi_joshi_narayan_2023, title={Microneedle-Integrated Device for Transdermal Sampling and Analyses of Targeted Biomarkers}, volume={4}, ISSN={["2688-4046"]}, url={http://dx.doi.org/10.1002/smsc.202200087}, DOI={10.1002/smsc.202200087}, abstractNote={Currently available point‐of‐care systems for body fluid collection exhibit poor integration with sensors. Herein, the design of a disposable device for interstitial fluid (ISF) extraction as well as glucose, lactate, and potassium ion (K+) monitoring is reported on. It is minimally invasive and appropriate for single use, minimizing the risk of infection to the user. This microscale device contains a 3D‐printed cap‐like structure with a four‐by‐four microneedle (MN) array, bioreceptor‐modified carbon fiber (CF)‐sensing surface, and negative pressure convection technology. These features are incorporated within a compact, self‐contained, and manually operated microscale device, which is capable of withdrawing ≈3.0 μL of ISF from the skin. MN arrays applied with an upward driving force may increase the ISF flow rate. Moreover, functionalized CF working electrodes (WE1, WE2, WE3) are shown to selectively detect lactate, glucose, and K+ with high sensitivities of 0.258, 0.549, and 0.657 μA μm−1 cm−2 and low detection limits of 0.01, 0.080, 0.05 μm, respectively. Ex vivo testing on porcine skin is used to detect the ISF levels of the biomarkers. The microscale device can be a replacement for current point‐of‐care diagnostic approaches.}, number={6}, journal={SMALL SCIENCE}, publisher={Wiley}, author={Shukla, Shubhangi and Machekposhti, Sina Azizi and Joshi, Naveen and Joshi, Pratik and Narayan, Roger J.}, year={2023}, month={Apr} }
 @article{kadian_chaulagain_joshi_alam_cui_shankar_manik_narayan_2023, title={Probe sonication-assisted rapid synthesis of highly fluorescent sulfur quantum dots}, volume={34}, ISSN={["1361-6528"]}, url={http://dx.doi.org/10.1088/1361-6528/acd00a}, DOI={10.1088/1361-6528/acd00a}, abstractNote={AbstractA new type of heavy-metal free single-element nanomaterial, called sulfur quantum dots (SQDs), has gained significant attention due to its advantages over traditional semiconductor QDs for several biomedical and optoelectronic applications. A straightforward and rapid synthesis approach for preparing highly fluorescent SQDs is needed to utilize this nanomaterial for technological applications. Until now, only a few synthesis approaches have been reported; however, these approaches are associated with long reaction times and low quantum yields (QY). Herein, we propose a novel optimized strategy to synthesize SQDs using a mix of probe sonication and heating, which reduces the reaction time usually needed from 125 h to a mere 15 min. The investigation employs cavitation and vibration effects of high energy acoustic waves to break down the bulk sulfur into nano-sized particles in the presence of highly alkaline medium and oleic acid. In contrast to previous reports, the obtained SQDs exhibited excellent aqueous solubility, desirable photostability, and a relatively high photoluminescence QY up to 10.4% without the need of any post-treatment. Additionally, the as-synthesized SQDs show excitation-dependent emission and excellent stability in different pH (2–12) and temperature (20 °C–80 °C) environments. Hence, this strategy opens a new pathway for rapid synthesis of SQDs and may facilitate the use of these materials for biomedical and optoelectronic applications.}, number={30}, journal={NANOTECHNOLOGY}, publisher={IOP Publishing}, author={Kadian, Sachin and Chaulagain, Narendra and Joshi, Naveen Narasimhachar and Alam, Kazi M. and Cui, Kai and Shankar, Karthik and Manik, Gaurav and Narayan, Roger J.}, year={2023}, month={Jul} }
 @article{joshi_shukla_khosla_vanderwal_stafslien_narayan_narayan_2023, title={Q-Carbon as an Emergent Surface Coating Material for Antimicrobial Applications}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85162676028&partnerID=MN8TOARS}, DOI={10.2139/ssrn.4467042}, abstractNote={Q-carbon is a newly discovered allotrope of carbon that exhibits unique functional properties and robust mechanical strength. We propose that the surface of the Q-carbon can be functionalized by doping it with silicon to enhance its performance as a potential implant material. As such, a coating of silicon-doped Q-carbon (Si-Q-carbon) is shown to minimize the formation of biofilm, thus reducing the risk of microbial infection. Here in, we report the formation of Si-Q-carbon coatings of varied thicknesses (10 nm and 20 nm) through the plasma-enhanced chemical vapor deposition (PECVD) technique. The surface composition and the bonding characteristics of the thin films were evaluated by Raman and XPS analysis and showed that the thinnest sample (10 nm) has high sp3 content with an ID/IG ratio of 0.11. Furthermore, wettability and surface energy calculations were undertaken to investigate the surface characteristics of the coatings. The 10 nm sample was found to be more hydrophilic with a water contact angle of 75.3 ± 0.64°. The antibacterial activity of Si-Q-carbon coatings was investigated using a Staphylococcus epidermidis agar plating technique and the adhesion of bacteria was explained in terms of the surface properties of the thin films. We demonstrate that the Si-Q-carbon coating with the highest sp3 content is hydrophilic and showed a 57% reduction in adhered biofilm relative to a glass control. We envisage the potential application of Q-carbon in arthroplasty devices with enhanced mechanical strength and resistance to periprosthetic joint infections (PJIs).}, journal={SSRN}, publisher={Elsevier BV}, author={Joshi, Naveen Narasimhachar and Shukla, Shubhangi and Khosla, Nayna and Vanderwal, Lyndsi and Stafslien, Shane and Narayan, J. and Narayan, Roger}, year={2023} }
 @article{joshi_shivashankar_narayan_2023, title={Surfactant-free synthesis and magnetic property evaluation of air-stable cobalt oxide nanostructures}, volume={4}, ISSN={["2632-959X"]}, url={https://doi.org/10.1088/2632-959X/acf4ae}, DOI={10.1088/2632-959X/acf4ae}, abstractNote={Abstract
               We report the synthesis of metastable cobalt oxide (CoO) nanostructures via the low-temperature microwave-assisted solvothermal (MAS) process. An alcoholic solution of cobalt (II) acetylacetonate in a sealed vessel was irradiated with microwaves at a temperature <150 °C and a pressure below 100 psi. As-synthesized powder material was characterized in terms of its structure and morphology. X-ray diffractometry (XRD) indicates the formation of well-crystallized CoO nanoparticles without the need for post-synthesis annealing. The mean crystallite size of the nanoparticles was estimated to be 41 nm. The morphology of the as-prepared powder sample was evaluated by field-emission scanning electron microscopy (FESEM), which revealed the formation of densely packed nanospheres of diameter <100 nm. The CoO nanospheres were obtained without the need for any surfactants or capping agents; they were found to be quite resistant to oxidation in ambient air over several months. We attribute the stability of CoO nanospheres to their dense packing, the driving force being the minimization of surface energy and surface area. Fourier-transform infrared (FT-IR) spectroscopy and Raman spectroscopy confirm the formation of phase-pure CoO nanostructures. The deconvolution of the active modes in Raman spectra obtained at room temperature reveals the Oh symmetry in rock-salt CoO produced by the MAS route. We have analyzed its effect on the magnetic characteristics of the CoO nanostructures. Isothermal field-dependent magnetization (MH) and inverse magnetic susceptibility measurements show a phase transition from antiferromagnetic to ferromagnetic interactions in the CoO nanostructures at around 10 K. The results indicate that the phenomenon of magnetic phase transition as a function of temperature is unique to CoO nanoparticles. This finding reveals the magnetic behavior of CoO nanostructures and presents opportunities for its possible application as an anisotropy source for magnetic recording.}, number={3}, journal={NANO EXPRESS}, author={Joshi, Naveen and Shivashankar, S. A. and Narayan, Roger}, year={2023}, month={Sep} }
 @article{narayan_sahoo_joshi_narayan_2023, title={Synthesis and novel properties of Q-silicon (January 2023)}, volume={11}, ISSN={["2166-3831"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85163376006&partnerID=MN8TOARS}, DOI={10.1080/21663831.2023.2224396}, abstractNote={We report the discovery of Q-silicon with an atomic density of 60% higher than crystalline silicon while keeping the bonding characteristics the same as normal silicon. Distinct amorphous phases are created, when one, two, or three tetrahedra are randomly packed, and a crystalline phase of Q-silicon is formed when subunit cells are arranged along <110> directions with alternate holes. Nanosecond laser melting of amorphous silicon in an undercooled state and quenching have created Q-silicon with robust ferromagnetism compared to the diamagnetism of silicon. The blocking temperature of Q-silicon is estimated to be over 400 K, thus opening a new frontier for spin-based computing and atomic-level storage. GRAPHICAL ABSTRACT IMPACT STATEMENT The discovery of Q-silicon having robust RT ferromagnetism will open a new frontier in atomic-scale spin-based devices and functional integration with nanoelectronics. Other properties of interest include enhanced hardness and superconductivity.}, number={8}, journal={MATERIALS RESEARCH LETTERS}, publisher={Informa UK Limited}, author={Narayan, Jagdish and Sahoo, Siba Sundar and Joshi, Naveen and Narayan, Roger}, year={2023}, month={Aug}, pages={688–696} }
 @article{joshi_shukla_gupta_joshi_narayan_narayan_2023, title={Synthesis of laser-patterned MoS2 nanoneedles for advanced electrochemical sensing}, volume={6}, ISSN={["2159-6867"]}, url={http://dx.doi.org/10.1557/s43579-023-00381-y}, DOI={10.1557/s43579-023-00381-y}, abstractNote={We describe a novel excimer laser-based route for the fabrication of crystalline MoS2 nanoneedles. Laser annealing of MoS2 thin films at a low energy density of 0.08 Jcm−2 resulted in a closed-pack structure with low defects and excellent conductivity due to melting and rapid quenching. A further increase in laser annealing energy density resulted in the formation of MoS2 nano-needles. This structure of MoS2 was found to have a remarkable reduction ability for H2O2 at − 0.14 V over a wide linear range; a low detection limit (0.45 nM (S/N = 3)) and sensitivity of 2.38 μA/mM cm−2 were demonstrated.}, number={4}, journal={MRS COMMUNICATIONS}, publisher={Springer Science and Business Media LLC}, author={Joshi, Pratik and Shukla, Shubhangi and Gupta, Siddharth and Joshi, Naveen and Narayan, Jagdish and Narayan, Roger}, year={2023}, month={Jun} }
 @article{joshi_shukla_narayan_2022, title={Novel photonic methods for diagnosis of
            <scp>SARS‐CoV</scp>
            ‐2 infection}, volume={4}, url={http://dx.doi.org/10.1002/tbio.202200001}, DOI={10.1002/tbio.202200001}, abstractNote={AbstractThe COVID‐19 pandemic that began in March 2020 continues in many countries. The ongoing pandemic makes early diagnosis a crucial part of efforts to prevent the spread of SARS‐CoV‐2 infections. As such, the development of a rapid, reliable, and low‐cost technique with increased sensitivity for detection of SARS‐CoV‐2 is an important priority of the scientific community. At present, nucleic acid‐based techniques are primarily used as the reference approach for the detection of SARS‐CoV‐2 infection. However, in several cases, false positive results have been observed with these techniques. Due to the drawbacks associated with existing techniques, the development of new techniques for the diagnosis of COVID‐19 is an important research activity. We provide an overview of novel diagnostic methods for SARS‐CoV‐2 diagnosis that integrate photonic technology with artificial intelligence. Recent developments in emerging diagnostic techniques based on the principles of advanced molecular spectroscopy and microscopy are considered.}, number={1-2}, journal={Translational Biophotonics}, publisher={Wiley}, author={Joshi, Naveen and Shukla, Shubhangi and Narayan, Roger}, year={2022}, month={Mar} }