Janus acoustically responsive scaffolds for sequential drug release with phase-programmed steady and pulsatile kinetics.

Achieving precise temporal control over drug release kinetics, including sequential delivery with varied profiles, is crucial for optimizing therapeutic outcomes. However, engineering systems capable of sequential release combining distinct kinetics (e.g.

Benzimidazole-based mononuclear polypyridyl Cu(II) complexes: DNA binding, cleavage, and antiproliferative studies.

This paper addresses the synthesis, characterization, DNA binding, cleavage, and antiproliferative activity studies of a series of heteroleptic mononuclear copper(II) complexes [Cu(L)(bpy)](ClO), {1}; [Cu(L)(phen)](ClO), {2}; and [Cu(L)(Mephen)](ClO), {3} derived from different polypyridyl ligands, where in the complex architecture, one 2,6-bis(1-methyl-1-benzo[]imidazol-2-yl)pyridine(Mebzimpy) (L) moiety is connected to the central Cu metal in a tridentate fashion and the bidentate co-ligands are 2,2'-bipyridine (bpy), 1,10-phenanthroline (phen) and 2,9-dimethyl-1,10-phenanthroline (Mephen). All the synthesized complexes were characterized using various spectroscopic and analytical methods, along with the single-crystal X-ray diffraction (SCXRD) technique. The complexes crystallize in a penta-coordinated distorted square pyramidal geometry.

Ultrasound-generated bubbles enhance osteogenic differentiation of mesenchymal stromal cells in composite collagen hydrogels.

Hydrogels can improve the delivery of mesenchymal stromal cells (MSCs) by providing crucial biophysical cues that mimic the extracellular matrix. The differentiation of MSCs is dependent on biophysical cues like stiffness and viscoelasticity, yet conventional hydrogels cannot be dynamically altered after fabrication and implantation to actively direct differentiation. We developed a composite hydrogel, consisting of type I collagen and phase-shift emulsion, where osteogenic differentiation of MSCs can be non-invasively modulated using ultrasound.

Mononuclear copper(II) complexes with polypyridyl ligands: synthesis, characterization, DNA interactions/cleavages and cytotoxicity towards human cancer cells.

DNA being the necessary element in cell regeneration, controlled cellular apoptosis DNA binding/cleaving is considered an approach to combat cancer cells. The widely prescribed metallodrug cisplatin has shown interactions with the guanine-N7 center, and a plethora of complexes are continually developed to enhance crosslinking properties as well as covalent and non-covalent interactions. Two pentadentate ligands, L1 (1-(6-(1-benzo[]imidazol-2-yl)pyridin-2-yl)-,-bis(pyridin-2-ylmethyl)methanamine) and L2 (1-(6-(1-methyl-1-benzo[]imidazol-2-yl)pyridin-2-yl)-,-bis(pyridin-2-ylmethyl)methanamine), were synthesized together with their respective copper(II) complexes [1](ClO) and [2](ClO), which crystallized in a trigonal bipyramidal fashion.

Chromophore appended DPA-based copper(II) complexes with a diimine motif towards DNA binding and fragmentation studies.

Mixed ligand copper(II) complexes [Cu(L1)(bpy)](ClO)1 and [Cu(L2)(bpy)](ClO)2 (where L1 = 1-(anthracen-9-yl)-,-bis(pyridin-2-ylmethyl)methanamine, L2 = 1-(pyren-1-yl)-,-bis(pyridin-2-ylmethyl)methanamine and bpy = 2,2'-bipyridine) were synthesised and characterised thoroughly different analytical and spectroscopic techniques , UV-vis spectroscopy, fluorescence spectroscopy, FT-IR spectroscopy, HRMS and EPR spectroscopy. The molecular structures of the synthesised complexes were obtained using the single-crystal X-ray diffraction technique. Both complexes exhibited penta-coordinated and acquired distorted square pyramidal geometry.

Fabrication and integration of a low-cost 3D printing-based glucose biosensor for bioprinted liver-on-a-chip.

In the last two decades, significant progress has been made in the development of more physiologically relevant organ-on-a-chip (OOC) systems that can mimic tissue microenvironments. Despite the advantages of these microphysiological systems, such as portability, ability to mimic physiological flow conditions, and reduction of the number of reagents required for preparation and detection, they lack real-time analyte detection with high accuracy. To address this limitation, biosensor technologies have been integrated with OOC systems to facilitate simultaneous analysis of different analytes with a single device.

Development of lumen-based perfusable 3D liver in vitro model using single-step bioprinting with composite bioinks.

Hepatic sinusoids are uniquely organized structures that help maintain a spectrum of hepatic functions. Although several in vitro liver models have been developed to replicate liver sinusoids, most of these platforms require complex, multi-step fabrication methods making it difficult to achieve truly three-dimensional (3D) channel geometries. In this study, a single-step bioprinting technique was demonstrated to simultaneously print a chip platform and develop a perfusable vascularized liver sinusoid in vitro model.

Emergent multipath COVID-19 specimen collection problem with green corridor through variable length GA.

The COVID-19 pandemic has spread worldwide exponentially. Typically, for testing, a provincial main government hospital cum testing center collects patients' specimens from remote health centers in the minimum possible time, satisfying the 'false negativity' constraint of the first collected specimen. With infrastructural developments throughout the world, multiple paths are available for transportation between two cities.

Mononuclear cobalt(II) complexes with polypyridyl ligands: Synthesis, characterization, DNA interactions and in vitro cytotoxicity towards human cancer cells.

Mononuclear cobalt(II) complexes [Co(L)Cl]; 1, [Co(L)(bpy)Cl]PF; 2, [Co(L)(phen)Cl]PF; 3 and [Co(L)Cl]; 4 (where L = N,N-bis(pyridin-2-ylmethyl)aniline, L = (2,4,6-trimethyl-N,N-bis(pyridin-2-ylmethyl)aniline, bpy = 2,2-bipyridine, phen = 1,10-phenanthroline) were synthesized and characterized by different analytical and spectroscopic methods. All the complexes were structurally identified by single-crystal X-ray crystallography. Penta-coordinated complex 1 adopted distorted trigonal bipyramidal and hexacoordinated complexes 2 and 3 having distorted octahedral geometry whereas tetra-coordinated complex 4 has distorted tetrahedral geometry.

Mononuclear Co(II) polypyridyl complexes: synthesis, molecular structure, DNA binding/cleavage, radical scavenging, docking studies and anticancer activities.

Mononuclear Co(II) complexes [Co(L)Cl]; 1, [Co(L)(bpy)Cl]PF; 2, [Co(L)(phen)Cl]PF; 3 and [Co(L)(pic)Cl]; 4, (where L = ,-bis(pyridin-2-ylmethyl)aniline, bpy = 2,2'-bipyridine, phen = 1,10-phenanthroline, pic = picolinic acid) were systematically synthesized and characterized by different analytical and spectroscopic methods. All the complexes were structurally identified by single-crystal X-ray diffraction analysis. Penta-coordinated complex 1 adopted a distorted trigonal bipyramidal geometry, whereas hexacoordinated complexes 2-4 have distorted octahedral geometry.

Engineering Hydrogels for the Development of Three-Dimensional In Vitro Models.

The superiority of in vitro 3D cultures over conventional 2D cell cultures is well recognized by the scientific community for its relevance in mimicking the native tissue architecture and functionality. The recent paradigm shift in the field of tissue engineering toward the development of 3D in vitro models can be realized with its myriad of applications, including drug screening, developing alternative diagnostics, and regenerative medicine. Hydrogels are considered the most suitable biomaterial for developing an in vitro model owing to their similarity in features to the extracellular microenvironment of native tissue.

Design, synthesis, structural, spectral, and redox properties and phenoxazinone synthase activity of tripodal pentacoordinate Mn(II) complexes with impressive turnover numbers.

Catechol oxidase (CO) and phenoxazinone synthase (PHS) are two enzymes of immense significance due to their capability to oxidize catechols and -aminophenols to -quinones and phenoxazinones, respectively. In this connection two mononuclear manganese complexes with the molecular framework [Mn(Ln)Cl]Cl {L1: tris((1-benzo[]imidazol-2-yl)methyl)amine; = 1 and L2: tris(-methylbenzimidazol-2-ylmethyl)amine; = 2} have been designed to be potential catalysts for OAPH (-aminophenol) oxidation. Both the ligands and their corresponding metal complexes have been successfully synthesized and thoroughly characterized by different spectroscopic and analytical techniques such as FT-IR, H NMR, UV-vis spectroscopy, EPR spectroscopy and ESI mass spectroscopy.

Synthesis, Characterization, and Water Oxidation Activity of Isomeric Ru Complexes.

The synthesis and characterization of the isomeric ruthenium complexes with the general formula and [Ru(trpy)(qc)X] (trpy is 2,2':6',2″-terpyridine, qc is 8-quinolinecarboxylate, and , X = Cl, = 0; and , X=OH, = 1) with respect to the relative disposition of the carboxylate and X ligands are reported. For comparison purposes, another set of ruthenium complexes with general formula and [Ru(trpy)(pic)(OH)] (pic is 2-picolinate (-, -)) have been prepared. The complexes with a qc ligand show a more distorted geometry compared to the complexes with a pic ligand.

Ground-State Proton-Transfer (GSPT)-Assisted Enhanced Two-Photon Uncaging from a Binol-based AIE-Fluorogenic Phototrigger.

We demonstrated for the first time without any chemical modification the two-photon absorption (TPA) cross-section can be enhanced and red-shifted to the near-infrared (NIR) region by the ground-state proton-transfer (GSPT) process. Using GSPT, we developed a simple binol-based aggregation-induced emission (AIE)-fluorogenic phototrigger having a large two-photon uncaging cross-section in the "phototherapeutic window". As a proof of concept, we showed our phototrigger for the release of two different anticancer drugs in the NIR region.

Near-IR light-induced photorelease of nitric oxide (NO) on ruthenium nitrosyl complexes: formation, reactivity, and biological effects.

Polypyridyl backbone nitrosyl complexes of ruthenium with the molecular framework [RuII(antpy)(bpy)NO+/˙]n+ [4](PF6)3 (n = 3), [4](PF6)2 (n = 2), where antpy = 4'-(anthracene-9-yl)-2,2':6',2''-terpyridine and bpy = 2,2'-bipyridine, were synthesized via a stepwise synthetic route from the chloro precursor [RuII(antpy)(bpy)(Cl)](PF6) [1](PF6) and [RuII(antpy)(bpy)(CH3CN)](PF6)2 [2](PF6)2 and [RuII(antpy)(bpy)(NO2)](PF6) [3](PF6). After column chromatographic purification, all the synthesized complexes were fully characterized using different spectroscopic and analytical techniques including mass spectroscopy, 1H NMR, FT-IR and UV-vis spectrophotometry. The Ru-NO stretching frequency of [4](PF6)3 was observed at 1941 cm-1, which suggests moderately strong Ru-NO bonding.

Nanotailored hyaluronic acid modified methylcellulose as an injectable scaffold with enhanced physico-rheological and biological aspects.

The collaborative endeavor in tissue engineering is to fabricate a bio-mimetic extracellular matrix to assist tissue regeneration. Thus, a novel injectable tissue scaffold was fabricated by exploring nanotailored hyaluronic acid (nHA) and methylcellulose (MC) (nHAMC) along with pristine HA based MC scaffold (HAMC). nHA with particle size ∼22 ± 5.

Fractal self-assembly and aggregation of human amylin.

Human amylin is an intrinsically disordered protein believed to have a central role in Type-II diabetes mellitus (T2DM). The formation of intermediate oligomers is a seminal event in the eventual self-assembled fibril structures of amylin. However, the recent experimental investigations have shown the presence of different self-assembled (oligomers, protofilaments, and fibrils) and aggregated structures (amorphous aggregates) of amylin formed during its aggregation.

Quinoline HS donor decorated fluorescent carbon dots: visible light responsive HS nanocarriers.

Recent studies have shown that the utility of nanocarriers for the transportation of gaseous signalling molecules to their target site in a biological environment is an effective approach. In this work, we have developed for the first time visible light responsive nanocarriers for the effective release of HS. Our newly developed nanocarriers for HS release are constructed using two main ingredients: fluorescent carbon dots and quinoline as an HS donor.

A water soluble light activated hydrogen sulfide donor induced by an excited state meta effect.

We have utilized an m-amino benzyl based photoremovable protecting group (PRPG) to develop a new water soluble HS donor. It efficiently releases HS on demand in a spatio-temporally controlled fashion by an excited state "meta effect" with good chemical and photochemical quantum yield in an aqueous environment. The efficient photorelease of HS under physiological conditions was also demonstrated by in vitro studies.

Promoted Osteoconduction of Polyurethane-Urea Based 3D Nanohybrid Scaffold through Nanohydroxyapatite Adorned Hierarchical Titanium Phosphate.

The lack of optimal physiological properties, bacterial colonization, and auto-osteoinduction, are the foremost issues of orthopedic implantations. In terms of bone healing, many researchers have reported the release of additional growth factors of the implanted biomaterials to accelerate the bone regeneration process. However, the additional growth factor may cause side effects such as contagion, nerve pain, and the formation of ectopic bone.

Restricted rotation of an Fe(CO)(PL)-subunit in [FeFe]-hydrogenase active site mimics by intramolecular ligation.

A new series of homodinuclear iron complexes as models of the [FeFe]-hydrogenase active site was prepared and characterized. The complexes of the general formula [Fe2(mcbdt)(CO)5PPh2R] (mcbdt = benzene-1,2-dithiol-3-carboxylic acid) feature covalent tethers that link the mcbdt ligand with the phosphine ligands which are terminally coordinated to one of the Fe centres. The synthetic feasability of the concept is demonstrated with the preparation of three novel complexes.

Development of gelatin/carboxymethyl chitosan/nano-hydroxyapatite composite 3D macroporous scaffold for bone tissue engineering applications.

The present study delineates a relatively simpler approach for fabrication of a macroporous three-dimensional scaffold for bone tissue engineering. The novelty of the work is to obtain a scaffold with macroporosity (interconnected networks) through a combined approach of high stirring induced foaming of the gelatin/carboxymethyl chitosan (CMC)/nano-hydroxyapatite (nHAp) matrix followed by freeze drying. The fabricated macroporous (SGC) scaffold had a greater pore size, higher porosity, higher water retention capacity, slow and sustained enzymatic degradation rate along with higher compressive strength compared to that of non-macroporous (NGC, prepared by conventional freeze drying methodology) scaffold.