A mono-funtionalised tetraphenylporphyrin (TPP) bearing valine moiety at the phenylring was synthesized for photocytotoxicity examination in four steps, starting from regiospecificmono-nitration of TPP at the phenyl r...A mono-funtionalised tetraphenylporphyrin (TPP) bearing valine moiety at the phenylring was synthesized for photocytotoxicity examination in four steps, starting from regiospecificmono-nitration of TPP at the phenyl ring. The in vitro photocytotoxicitic effect against SPC-Aladenocarcinona cell line was tested.展开更多
The antibacterial activities,cytotoxicity,and wound healing of amine(3-aminopropyltriethoxysilane (APTES))-functionalised zeolite Y against normal human fibroblast cells were studied.The characterisation of unmodified...The antibacterial activities,cytotoxicity,and wound healing of amine(3-aminopropyltriethoxysilane (APTES))-functionalised zeolite Y against normal human fibroblast cells were studied.The characterisation of unmodified and amine-functionalised zeolites Y (Z,ZA 0.04,ZA 0.4,and ZA 0.6) by Fourier transform infrared spectroscopy,X-ray powder diffraction,and energy dispersive X-ray analysis proved that the APTES molecules were grafted onto the zeolite Y surface without distorting its framework structure.All amine-functionalised zeolite Y samples possessed antibacterial activities against several ATCC bacteria that were correlated with the increased amount of APTES on the zeolite Y surface.Conversely,when a higher concentration of APTES was grafted on the zeolite Y,higher cytotoxicity was observed against the fibroblast cells.Although the ZA 0.6 sample (zeolite Y functionalised with 0.6 M of APTES) had higher antibacterial activity,it was cytotoxic to the cells.Therefore,the selection of an antibacterial agent for human treatment purposes must also consider its cytotoxicity effect against human cells to ensure it is biocompatible.展开更多
Synthesised triphenylphosphine-linked multiwalled carbon nanotubes (Tpp-MWCNTs) were used to study the adsorption of nickel in aqueous solutions and their adsorption capabilities were compared with purified MWCNTs.T...Synthesised triphenylphosphine-linked multiwalled carbon nanotubes (Tpp-MWCNTs) were used to study the adsorption of nickel in aqueous solutions and their adsorption capabilities were compared with purified MWCNTs.The adsorption capacity increased with an increase in pH for all adsorbents.The adsorption equilibrium was reached in 40 and 30 min for purified MWCNTs and Tpp-MWCNTs,respectively.Both Freundlich and Langmuir isotherms used to investigate the adsorption process fitted the experimental data well with the correlation coefficient R 2 close to 1 for all adsorbents.On the other hand,the experimental data fitted well with a pseudo secondorder model.The speciation of nickel also influenced the adsorption on the purified and Tpp-MWCNTs.The adsorbents used in this study showed superior adsorption capacity when compared to other adsorbents reported in the literature.展开更多
A smart hybrid conversion coating has been developed. Modifications of coating solutions with poly-hydroxyl organic materials to reduce the usual mud cracking pattern characteristics of chromate conversion coatings (C...A smart hybrid conversion coating has been developed. Modifications of coating solutions with poly-hydroxyl organic materials to reduce the usual mud cracking pattern characteristics of chromate conversion coatings (CCCs) and improve its ability to release inhibitors to corroding sites have been achieved. The smart functionalised chromate conversion coating (SFCCC), developed on aluminium substrate has undergone laboratory checks and commercial runs under factory conditions confirmed its potency in improving corrosion resistance and paint adhesion to metal surfaces. In-service performance of the coating in the past three years is excellent.展开更多
Objective: The presence of nerve fibers in human endometrium remains unsettled but recent immunocytochemical studies have shown that there was increased innervation in the endometrium from women with endometriosis and...Objective: The presence of nerve fibers in human endometrium remains unsettled but recent immunocytochemical studies have shown that there was increased innervation in the endometrium from women with endometriosis and some nerve fibers in the normally cycling human endometrium. In the current study, we used uterine tissue cryosections from normal cycling women, which previously provided better immunocytochemical staining for lymphatic vessels than in paraffin sections. Materials and Methods: A total of 16 cases from normally cycling women were included representing menstrual, early proliferative, early to late secretary phase. Neurofilament and CD 56 were used as immunocytochemical markers for nerve fibers with cryosections. Results: There were consistent presence of nerve fibers in myometrium and basalis. Few small nerve fibers were identified in early proliferative endometrium and more nerve fibers were present in lower-half functionalis from mid-secretary phase. Late-secretary functionalis showed less nerve fibers in the upper-half than the lower-half functionalis, implying growing nerve fibers from lower functionalis to upper functionalis in late-secretary phase. Conclusion: Nerve fibers appeared to cyclically grow from basalis to lower functionalis and then from lower functionalis to upper functionalis concomitantly with blood vessels in normally cycling human endometrium. These cycling endometrial nerve fibers consisted mostly of nonmyelinated small nerve fibers, which may transmit pelvic pain in the normally cycling women.展开更多
Because of their tissue-like mechanical performances,high biocompatibility,and adjust-able functionality,hydrogels have become increasingly attractive materials for promoting wound healing.Chronic wounds include burn,...Because of their tissue-like mechanical performances,high biocompatibility,and adjust-able functionality,hydrogels have become increasingly attractive materials for promoting wound healing.Chronic wounds include burn,diabetic,and infected wounds.Unlike common incision wounds,chronic wounds are more challenging to heal.To meet the clinical needs,multifunctional hydrogels should be fabricated and investigated.To guide future studies on the fabrication of hydrogel-based chronic wound dressings,a review of advanced multifunctional hydrogels is necessary.Various hydrogels with advanced properties,such as antibacterial,antioxidant,bioadhesive,anti-inflammatory,and wound healing properties,that can be used for skin burn wounds and diabetic wounds are summarised.Lastly,the prospects of advanced hydrogels for wound healing are elaborated.展开更多
Fourier transform infrared spectroscopy(FTIR)is one of the most widely used vibrational diagnostic techniques to investigate gas-phase reactive oxygen and nitrogen species(RONS).However,the technique carries intrinsic...Fourier transform infrared spectroscopy(FTIR)is one of the most widely used vibrational diagnostic techniques to investigate gas-phase reactive oxygen and nitrogen species(RONS).However,the technique carries intrinsic challenges,particularly in relation to interfering peaks in the spectral data.This study explores the interfacial processes that occur when reactive oxygen and nitrogen species generated by a non-equilibrium air plasma interact with the metal halide windows of an FTIR gas cell,leading to the appearance and evolution of spurious absorption peaks which complicate spectral interpretation.Raman spectroscopy,X-ray photoelectron spectroscopy,time of flight secondary ion mass spectrometry and attenuated total reflectance-FTIR spectroscopy were used to elucidate the origin of spurious absorption peaks spanning the 1400-1300 cm^(-1)spectral range as a result of KBr exposure to plasma generated species.It was found that plasma exposed KBr contained a lower atomic fraction of Br which was replaced by the NO3nitrate group,the main absorbance peak of which progressively evolved with plasma exposure and affected the window transparency over the corresponding FTIR region.A correlation was revealed between KNO_(3)formation,plasma power and exposure time to a growth and change in molecular vibrational energies corresponding to asymmetric NO3stretching vibrations in the KNO_(3)structure.展开更多
Superparamagnetic iron oxide nanoparticles with narrow size distributions were successfully prepared in large scale by a facile one-pot synthetic method in the presence of hydrophilic polymers, such as polyethylene gl...Superparamagnetic iron oxide nanoparticles with narrow size distributions were successfully prepared in large scale by a facile one-pot synthetic method in the presence of hydrophilic polymers, such as polyethylene glycol dia-cid (HOOC-PEG-COOH) and poly(acrylic acid) (PAA). The as-prepared products were investigated in detail by powder X-ray diffraction (XRD), thermogravimetric analyses (TGA), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), dynamic light scattering (DLS), and vibrating sample magnetometer (VSM). The interaction between polymers and iron oxide nanoparticles was investigated using Fou-rier transform infrared spectrometry (FT-IR). The results show that polymers can be attached onto the surface of iron oxide nanoparticle by bridging coordination and monodentate fashion, respectively. The interaction affects iron oxide nanoparticle properties significantly, such as XRD diffraction intensity, hydrodynamic diameter, isoelectric point, and saturation magnetization. Furthermore, the results of in vitro experiments indicated that iron oxide-PEG-COOH nanoparticle is more cytotoxie than iron oxide-PAA nanoparticle due to different coordinating modes.展开更多
The electrical properties of chemically derived graphene and graphene grown by chemical vapor deposition (CVD), until now, have been inferior to those of mechanically exfoliated graphene. However, because graphene i...The electrical properties of chemically derived graphene and graphene grown by chemical vapor deposition (CVD), until now, have been inferior to those of mechanically exfoliated graphene. However, because graphene is easier to produce in large quantities through CVD or growth from solid carbon sources, it has a higher potential for use in future electronics applications. Generally, modifications to the pristine lattice structure of graphene tend to adversely affect the electrical properties by shifting the doping level and changing the conductivity and the mobility. Here we show that a small degree of graphene surface functionalization, using diazonium salts with electron-withdrawing and electron-donating functional groups, is sufficient to predominantly induce p-type doping, undiminished mobility, and higher conductivity at the neutrality point. Molecules without a diazonium anchor group desorb easily and do not have a significant effect on the electronic properties of graphene devices. We further demonstrate the variability between identically fabricated pristine devices, thereby underscoring the caution needed when characterizing graphene device behaviors lest conclusions be drawn based on singular extremes.展开更多
文摘A mono-funtionalised tetraphenylporphyrin (TPP) bearing valine moiety at the phenylring was synthesized for photocytotoxicity examination in four steps, starting from regiospecificmono-nitration of TPP at the phenyl ring. The in vitro photocytotoxicitic effect against SPC-Aladenocarcinona cell line was tested.
文摘The antibacterial activities,cytotoxicity,and wound healing of amine(3-aminopropyltriethoxysilane (APTES))-functionalised zeolite Y against normal human fibroblast cells were studied.The characterisation of unmodified and amine-functionalised zeolites Y (Z,ZA 0.04,ZA 0.4,and ZA 0.6) by Fourier transform infrared spectroscopy,X-ray powder diffraction,and energy dispersive X-ray analysis proved that the APTES molecules were grafted onto the zeolite Y surface without distorting its framework structure.All amine-functionalised zeolite Y samples possessed antibacterial activities against several ATCC bacteria that were correlated with the increased amount of APTES on the zeolite Y surface.Conversely,when a higher concentration of APTES was grafted on the zeolite Y,higher cytotoxicity was observed against the fibroblast cells.Although the ZA 0.6 sample (zeolite Y functionalised with 0.6 M of APTES) had higher antibacterial activity,it was cytotoxic to the cells.Therefore,the selection of an antibacterial agent for human treatment purposes must also consider its cytotoxicity effect against human cells to ensure it is biocompatible.
基金The Grant-Holder-Linked Bursary received from the National Research Foundation and the bursary granted by the Department of Chemical Technology to Mr. A. A
文摘Synthesised triphenylphosphine-linked multiwalled carbon nanotubes (Tpp-MWCNTs) were used to study the adsorption of nickel in aqueous solutions and their adsorption capabilities were compared with purified MWCNTs.The adsorption capacity increased with an increase in pH for all adsorbents.The adsorption equilibrium was reached in 40 and 30 min for purified MWCNTs and Tpp-MWCNTs,respectively.Both Freundlich and Langmuir isotherms used to investigate the adsorption process fitted the experimental data well with the correlation coefficient R 2 close to 1 for all adsorbents.On the other hand,the experimental data fitted well with a pseudo secondorder model.The speciation of nickel also influenced the adsorption on the purified and Tpp-MWCNTs.The adsorbents used in this study showed superior adsorption capacity when compared to other adsorbents reported in the literature.
文摘A smart hybrid conversion coating has been developed. Modifications of coating solutions with poly-hydroxyl organic materials to reduce the usual mud cracking pattern characteristics of chromate conversion coatings (CCCs) and improve its ability to release inhibitors to corroding sites have been achieved. The smart functionalised chromate conversion coating (SFCCC), developed on aluminium substrate has undergone laboratory checks and commercial runs under factory conditions confirmed its potency in improving corrosion resistance and paint adhesion to metal surfaces. In-service performance of the coating in the past three years is excellent.
文摘Objective: The presence of nerve fibers in human endometrium remains unsettled but recent immunocytochemical studies have shown that there was increased innervation in the endometrium from women with endometriosis and some nerve fibers in the normally cycling human endometrium. In the current study, we used uterine tissue cryosections from normal cycling women, which previously provided better immunocytochemical staining for lymphatic vessels than in paraffin sections. Materials and Methods: A total of 16 cases from normally cycling women were included representing menstrual, early proliferative, early to late secretary phase. Neurofilament and CD 56 were used as immunocytochemical markers for nerve fibers with cryosections. Results: There were consistent presence of nerve fibers in myometrium and basalis. Few small nerve fibers were identified in early proliferative endometrium and more nerve fibers were present in lower-half functionalis from mid-secretary phase. Late-secretary functionalis showed less nerve fibers in the upper-half than the lower-half functionalis, implying growing nerve fibers from lower functionalis to upper functionalis in late-secretary phase. Conclusion: Nerve fibers appeared to cyclically grow from basalis to lower functionalis and then from lower functionalis to upper functionalis concomitantly with blood vessels in normally cycling human endometrium. These cycling endometrial nerve fibers consisted mostly of nonmyelinated small nerve fibers, which may transmit pelvic pain in the normally cycling women.
基金Sichuan Science and Technology Program,Grant/Award Number:2022YFS0040Guangdong Basic and Applied Basic Research Foundation,Grant/Award Number:2021B1515120019+3 种基金Fundamental Research Funds for Central Universities,Grant/Award Numbers:2682020ZT79,202241010Shenzhen Funds of the Central Government to Guide Local Scientific and Technological Development,Grant/Award Number:2021SZVUP123Excellent Young Scientist Foundation of Shandong Province,Grant/Award Number:ZR202110120029NSFC,Grant/Award Number:82072071。
文摘Because of their tissue-like mechanical performances,high biocompatibility,and adjust-able functionality,hydrogels have become increasingly attractive materials for promoting wound healing.Chronic wounds include burn,diabetic,and infected wounds.Unlike common incision wounds,chronic wounds are more challenging to heal.To meet the clinical needs,multifunctional hydrogels should be fabricated and investigated.To guide future studies on the fabrication of hydrogel-based chronic wound dressings,a review of advanced multifunctional hydrogels is necessary.Various hydrogels with advanced properties,such as antibacterial,antioxidant,bioadhesive,anti-inflammatory,and wound healing properties,that can be used for skin burn wounds and diabetic wounds are summarised.Lastly,the prospects of advanced hydrogels for wound healing are elaborated.
基金financial support from the Public Agency for Research Activity of the Republic of Slovenia(awards J2-4490,J2-4451 and L2-4481)the UK Engineering and Physical Sciences Research Council(EPSRC)(awards EP/S025790/1 and EP/N021347/1)NATO(award G5814)
文摘Fourier transform infrared spectroscopy(FTIR)is one of the most widely used vibrational diagnostic techniques to investigate gas-phase reactive oxygen and nitrogen species(RONS).However,the technique carries intrinsic challenges,particularly in relation to interfering peaks in the spectral data.This study explores the interfacial processes that occur when reactive oxygen and nitrogen species generated by a non-equilibrium air plasma interact with the metal halide windows of an FTIR gas cell,leading to the appearance and evolution of spurious absorption peaks which complicate spectral interpretation.Raman spectroscopy,X-ray photoelectron spectroscopy,time of flight secondary ion mass spectrometry and attenuated total reflectance-FTIR spectroscopy were used to elucidate the origin of spurious absorption peaks spanning the 1400-1300 cm^(-1)spectral range as a result of KBr exposure to plasma generated species.It was found that plasma exposed KBr contained a lower atomic fraction of Br which was replaced by the NO3nitrate group,the main absorbance peak of which progressively evolved with plasma exposure and affected the window transparency over the corresponding FTIR region.A correlation was revealed between KNO_(3)formation,plasma power and exposure time to a growth and change in molecular vibrational energies corresponding to asymmetric NO3stretching vibrations in the KNO_(3)structure.
基金The authors are grateful to the financial supports from National Natural Science Foundation of China (30970819), Shanghai Science and Technology Com-mittee (09XD1402900), and Shanghai Leading Aca-demic Discipline Project (S30203).
文摘Superparamagnetic iron oxide nanoparticles with narrow size distributions were successfully prepared in large scale by a facile one-pot synthetic method in the presence of hydrophilic polymers, such as polyethylene glycol dia-cid (HOOC-PEG-COOH) and poly(acrylic acid) (PAA). The as-prepared products were investigated in detail by powder X-ray diffraction (XRD), thermogravimetric analyses (TGA), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), dynamic light scattering (DLS), and vibrating sample magnetometer (VSM). The interaction between polymers and iron oxide nanoparticles was investigated using Fou-rier transform infrared spectrometry (FT-IR). The results show that polymers can be attached onto the surface of iron oxide nanoparticle by bridging coordination and monodentate fashion, respectively. The interaction affects iron oxide nanoparticle properties significantly, such as XRD diffraction intensity, hydrodynamic diameter, isoelectric point, and saturation magnetization. Furthermore, the results of in vitro experiments indicated that iron oxide-PEG-COOH nanoparticle is more cytotoxie than iron oxide-PAA nanoparticle due to different coordinating modes.
文摘The electrical properties of chemically derived graphene and graphene grown by chemical vapor deposition (CVD), until now, have been inferior to those of mechanically exfoliated graphene. However, because graphene is easier to produce in large quantities through CVD or growth from solid carbon sources, it has a higher potential for use in future electronics applications. Generally, modifications to the pristine lattice structure of graphene tend to adversely affect the electrical properties by shifting the doping level and changing the conductivity and the mobility. Here we show that a small degree of graphene surface functionalization, using diazonium salts with electron-withdrawing and electron-donating functional groups, is sufficient to predominantly induce p-type doping, undiminished mobility, and higher conductivity at the neutrality point. Molecules without a diazonium anchor group desorb easily and do not have a significant effect on the electronic properties of graphene devices. We further demonstrate the variability between identically fabricated pristine devices, thereby underscoring the caution needed when characterizing graphene device behaviors lest conclusions be drawn based on singular extremes.