Publications

A facile one-step reaction of [60]fullerene with cinnamaldehydes and amines promoted by magnesium perchlorate/ferric perchlorate under air conditions afforded a series of rare amino-substituted cyclopentafullerenes in moderate to good yields. Stereoselectivity was readily achieved. Secondary amines exclusively produced N,N-disubstituted cyclopentafullerenes as cis isomers, while arylamines gave N-monosubstituted cyclopentafullerenes with a preference of cis isomers as major products. N-Monosubstituted cyclopentafullerenes could be further converted into other scarce cyclopentafullerenes in the presence of acid chloride or paraformaldehyde. A possible reaction pathway was proposed to elucidate the formation of amino-substituted cyclopentafullerenes.

In this paper, we report on the large-scale, rapid synthesis of uniform rectangular coordination polymer nanoplates (RCPNs) assembled from Cu(II) and 4,4'-bipyridine for the first time. We further demonstrate that such RCPNs can be used as a very effective fluorescent sensing platform for multiple DNA detection with a detection limit as low as 30 pM and a high selectivity down to single-base mismatch. The DNA detection is accomplished by the following two steps: (1) RCPN binds dye-labeled single-stranded DNA (ssDNA) probe, which brings dye and RCPN into close proximity, leading to fluorescence quenching; (2) Specific hybridization of the probe with its target generates a double-stranded DNA (dsDNA) which detaches from RCPN, leading to fluorescence recovery. It suggests that this sensing system can well discriminate complementary and mismatched DNA sequences. The exact mechanism of fluorescence quenching involved is elucidated experimentally and its use in a human blood serum system is also demonstrated successfully.

With the continuous quest of developing hydrogel for cartilage regeneration with superior mechanobiological properties are still becoming a challenge. Chitosan (CS) hydrogels are the promising implant materials due to an analogous character of the soft tissue; however, their low mechanical strength and durability together with its lack of integrity with surrounding tissues hinder the load-bearing application. This can be solved by developing a composite chitosan hydrogel reinforced with Hydroxyapatite Nanorods (HANr). The objective of this work is to develop and characterize (physically, chemically, mechanically and biologically) the composite hydrogels loaded with different concentration of hydroxyapatite nanorod. The concentration of hydroxyapatite in the composite hydrogel was optimized and it was found that, reinforcement modifies the hydrogel network by promoting the secondary crosslinking. The compression strength could reach 1.62 ± 0.02 MPa with a significant deformation of 32% and exhibits time-dependent, rapid self-recoverable and fatigue resistant behavior based on the cyclic loading-unloading compression test. The storage modulus value can reach nearly 10 kPa which is needed for the proposed application. Besides, composite hydrogels show an excellent antimicrobial activity against Escherichia coli, Staphylococcus aureus bacteria's and Candida albicans fungi and their cytocompatibility towards L929 mouse fibroblasts provide a potential pathway to developing a composite hydrogel for cartilage regeneration.

ABSTRACT Aloe vera (AV) gel has been widely used in various medical, cosmetic, and nutraceutical applications. However, AV rind, the tougher outer layer of AV leaves where the cell wall components exists, is currently treated as a fertilizer or waste. This study aimed to investigate the potential of the AV rind as a resource for the production of cellulose nanofibers. Since a detailed analysis of the AV rind has been lacking, chemical composition of rind was analyzed before processing it into nanofibers. The results showed that AV rind has a high proportion of α ‐cellulose (57.72% ± 2.18%). AV rind nanofibers (AVRNF) were prepared using chemi‐mechanical process. The morphological analyses showed that most of the isolated fibers were individual fibers under 20 nm. Crystallinity and degree of polymerization of the obtained AVRNF, and mechanical properties of the nanofibrous film were evaluated and compared with the wood nanofibers. Tensile strength of AVRNF film (102 MPa) was comparatively lower than the wood fibers (132 MPa), which was consistent with the lower crystallinity of AVRNF [crystallinity index (CI) = 0.66] as well as the lower degree of polymerization (DP = 396), compared with wood fibers (CI = 0.90, DP = 1297). © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131 , 40592.

The growing environmental awareness toward the replacement of non-biodegradable materials with biodegradable materials has led many researchers for looking at many bio-based materials to suit various applications. This study objective to evaluate the morphology and properties of fibers extracted from Citrullus lanatus climber. The physical-chemical, thermal, mechanical, crystalline, morphological characteristics of Citrullus lanatus climber fibers were examined by Fourier transform-infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), single fiber tension test, X-ray diffraction (XRD), and scanning electron microscope (SEM). The test results showed cellulose content (53.7 wt. %), density (1227 kg/m3), crystallinity index (33.33%) which prove that Citrullus lanatus climber fibers can be used as reinforcement for light-weight medium load applications.

Tyrosine-protein kinase CSK otherwise known as C-terminal Src kinase (CSK), is involved in multiple pathways and processes, including regulating cell growth, differentiation, migration, and immune responses. Altered expression of CSK has been associated with various complexities, including cancer, CD45 deficiency, Osteopetrosis and lupus erythematosus. Important auxiliary roles of CSK in cancer progression make it a crucial target in developing novel anticancer therapy. Thus, CSK inhibitors are of concern as potent immuno-oncology agents. In this perspective, phytochemicals can be a significant source for unraveling novel CSK inhibitors. In this study, we carried out a systematic structure-based virtual screening of bioactive phytoconstituents against CSK to identify its potential inhibitors. After a multi-step screening process, two hits (Shinpterocarpin and Justicidin B) were selected based on their druglike properties and binding affinity towards CSK. The selected hits were further analyzed for their stability and interaction via all-atom molecular dynamics (MD) simulations. The selected hits indicated their potential as selective binding partners of CSK, which can further be used for therapeutic development against CSK-associated malignancies.Communicated by Ramaswamy H. Sarma.

A NiMo hollow nanorod array is developed on Ti mesh <italic>via</italic> a template-assisted electrodeposition method as a bifunctional electrode for water splitting.