SYNTHESIS AND CHARACTERIZATION OF TITANIA NANOTUBES FOR DYE WASTEWATER TREATMENT

KUEN-SONG LIN,CHAO-CHUN LO,NI-BIN CHANG 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2008 NANO Vol.3 No.4

This paper starts with the preparation of anatase titania nanotube (TN) in large quantities by hydrothermal routes with different calcination temperatures, and then delves into a thorough investigation for the characterization of fine structures or formation mechanism of TN. Experimentally, anatase TiO2 nanoparticle was used as a precursor for TN synthesis. The results showed that the length and diameter of TN range are 50–100 nm and 10–15 nm, respectively. The XRD patterns and BET isotherms indicated that TN owns anatase-typed structures with a surface area of 292m2/g. By extended X-ray absorption fine structure (EXAFS) spectra, the valency and framework of TN are Ti(IV) with octahedral structures. The EXAFS data also revealed that TN has a first shell of Ti–O bonding with bond distances of 1.95 Å and coordination numbers were 2. The results revealed that the TiO2 anatase nanoparticles can be solved into layer under strong alkaline. The layer of TN further curling itself to reduce the energetics was postulated and found. For calcination temperature larger than 400°C, the microstructure of TN might transform from nanotube into nanoparticles accompanying with the sharp increase for the nanoparticle crystalline phase. With the understanding of pore structure variation on the basic dye (Basic Green 5 (BG5)), the adsorption ability, mechanisms, and kinetics of (Basic Green 5 (BG5)) dye onto TN were examined as well.

DECONTAMINATION OF NITRATES AND NITRITES IN WASTEWATER BY ZERO-VALENT IRON NANOPARTICLES

KUEN-SONG LIN,TIEN-DENG CHUANG,NI-BIN CHANG 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2008 NANO Vol.3 No.4

The chemical reduction of nitrate or nitrite species by zero-valent iron nanoparticle (ZVIN) in aqueous solution and related reaction kinetics or mechanisms using fine structure characterization were investigated. Experimentally, ZVIN of this study was prepared by borohydride reduction method at room temperature. The morphology of as-synthesized ZVIN shows that the nearly ball and ultrafine particles ranged of 20–50 nm were observed with FE-SEM analysis. The kinetic model of nitrites or nitrates reductive reaction by ZVIN is proposed as a pseudo-first-order kinetic equation. The nitrite and nitrate removal efficiencies using ZVIN were found 65–83% and 51–68%, respectively, based on three different initial concentrations. By using XRD patterns, the quantitative relationship between nitrite and Fe(III) or Fe(II) becomes similar to the one between nitrate and Fe(III) in the ZVIN study. The possible reason is linked with a faster nitrite reduction by ZVIN. In fact,the occurrence of the relative faster nitrite reductive reaction suggested that the passivation of the ZVIN have a significant contribution to iron corrosion. The XANES spectra show that the nitrites or nitrates reduce to N₂ while oxidizing the ZVIN to Fe₂O₃ or Fe₃O₄ electrochemically. It is also very clear that decontamination of nitrate or nitrite species in groundwater via the in-situ remediation with a ZVIN permeable reactive barrier would be environmentally attractive.

In vitro study of doxorubicin-loaded thermo- and pH-tunable carriers for targeted drug delivery to liver cancer cells

Sikhumbuzo Charles Kunene,KUEN-SONG LIN,Meng-Tzu Weng,Maria Janina Carrera Espinoza,Chun-Ming Wu 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.104 No.-

In this study, a series of thermo- and pH-dependent doxorubicin (DOX) carriers based on magnetic graphenenanosheets (MGNSs), functionalized by poly(N-isopropylacrylamide) (PNIPAM) and polyethylenemine(PEI) nanogel, targeting liver cancer cells were formulated. The temperature phase transitions of thecarriers can be tuned as a function of pH to the intended value in the range of 38–42 C. In vitro studiesshowed a high cell viability of above 90% at all doses of MGNSs and MGNS-nanogel against HEK293T normaland HepG2 cancerous cells, confirming the biocompatibility and nontoxicity of the carriers. In comparison,the MGNS-nanogel-DOX demonstrated a sufficient therapeutic effect towards HepG2 cell line. The cell viability results showed enhanced efficacy of the drug released by means of applied magneticfield (AMF). Moreover, an efficient cellular intake of the carriers into the HepG2 cells was achieved. Additionally, the achieved low DOX release at a lower temperature and neutral pH can retain the drugin the carriers until reaching the targeted sites. Nevertheless, the high drug release showed that therelease was triggered by high temperature and acidic pH. Hence, the developed thermo- and pHtunableMGNS-nanogel-DOX showed a high potential for microenvironment stimulus-prompted drugdelivery and cancer cell suppression.

In vitro intracellular studies of pH and thermo-triggered doxorubicin conjugated magnetic SBA-15 mesoporous nanocarriers for anticancer activity against hepatocellular carcinoma

Ndumiso Vukile Mdlovu,KUEN-SONG LIN,Meng-Tzu Weng,Chi-Cheng Hsieh,You-Sheng Lin,Maria Janina Carrera Espinoza 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.102 No.-

Hepatocellular carcinoma (HCC) is the most prevalent type of liver cancer, accounting for about 75% of allliver cancers. It is the third most common basis for cancer mortality worldwide, and unfortunately, itstreatment is often limited by the shortage of appropriate therapeutic options and side effects causedby the current treatment methods. To overcome this, doxorubicin (DOX)-loaded pH-/thermoresponsivemagnetic mesoporous nanocarriers were formulated and evaluated for their in vitro anticanceractivity against HCC. These nanocarriers consist of iron oxide (IO) nanoparticles conjugated withSBA-15 (S15) and Pluronic F127 (PF) to form IOS15 nanocomposites and IOS15@PF nanocarriers. The preparednanocarriers were superparamagnetic with saturation magnetizations of IOS15 and IOS15@PFbeing 76.3 and 72.1 emu/g, respectively. Small-angle neutron/X-ray scattering (SANS/SAXS) studiesshowed that the developed nanocarriers are temperature-sensitive and possess hexagonally arrangedstructures. Cell viability studies demonstrated that IOS15@PF@DOX nanocomplexes induced more apoptosisor necrosis. A temperature (69% release after 48 h)- and pH (70% release after 48 h)-dependent DOXrelease was observed, whereby more DOX was released at a high temperature of 42 C and pH value of5.4. Thus, the developed nanocarriers possess great potential for use in the targeted delivery of conventionalchemotherapeutic drugs with enhanced efficiency.

In vivo and in vitro studies of magnetic silica nanocomposites decorated with Pluronic F127 for controlled drug delivery system

Maria Janina Carrera Espinoza,KUEN-SONG LIN,Meng-Tzu Weng,Sikhumbuzo Charles Kunene,Shin-Yun Liu,You-Sheng Lin 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.115 No.-

The current study presents the synthesis and characterization of magnetic silica nanocomposites(MSNCs) decorated with Pluronic F127. The nanocomposites were loaded with doxorubicin (DOX) forhepatocellular carcinoma (HCC) therapy. The X-ray diffraction (XRD) patterns proved that the nanocompositeswere crystalline with diffraction peaks at 2h = 35.44 corresponding to (311) plane of Fe3O4. Thein vitro test demonstrated cell viability of above 90% revealing that MSNCs-F127 were biocompatible andnontoxic to the HEK293T and HepG2 cell lines; however, the MSNCs-F127-DOX formulations exhibited asignificant therapeutic effect against HepG2 cells. A pH-responsive drug release was detected, showing aHiguchi kinetic model at acidic and physiological conditions which demonstrated the best correlationcoefficient with R2 values of 0.969, and 0.932, respectively. The highest level of cell inhibitory rate, necrosis,and apoptosis in mice treated with MSNCs-F127-DOX was achieved by in vivo experiment, hematoxylinand eosin (H&E), and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)staining. The in vivo experiment revealed a significant tumor inhibition after treatment with MSNCs-F127-DOX. The prepared MSNCs-F127-DOX formulations could be utilized as an innovative drug deliverysystem (DDS) for anticancer therapy for several cancer types.

Biomimetic targeting magnetite hollow nanostructures based on pH-responsive benzoic-imine bonds for antitumor activity

Sikhumbuzo Charles Kunene,Kuen-Song Lin,Meng-Tzu Weng,Maria Janina Carrera Espinoza,You-Sheng Lin,Yi-Ting Lin 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.123 No.-

In this study, versatile homotypic-targeting and PEGylated magnetite hollow nanostructures (MHNs) thatare pH-responsive used as doxorubicin (DOX) nanocarriers are demonstrated. Cancer cell membrane(CM) and polyethylene glycol (PEG) functionalization through benzoic imine bonds endows DOXconjugatednanocarriers with enhanced tumor accumulation and penetration, biomimetic-targetingspecificity, as well as on-demand drug release, which improves their antitumor efficacy. The characteristicdiffraction peaks of magnetite nanocarriers at 35 indexed as (311) plane of magnetite can beobserved. Hierarchical mesoporous nanostructures with specific pore size distributions of approximately99.9, 97.2, and 95.6%, were developed. In vitro studies revealed that drug-free nanostructures exhibitedexcellent biocompatibility with more than 95% cell viability. In contrast, drug-conjugated nanostructuresdemonstrated high therapeutic effect, pH-responsive drug release, and enhanced intracellular uptake inHepG2 cells. In vivostudies showed that the MHNC–DOX–PEG/CM formulations displayed the best antitumorefficacy, with the lowest tumor volume and weight. Furthermore, significantly large apoptotic andnecrotic areas were identified in the tumor tissues from the DOX-conjugated groups, but no noticeableinflammation or hemorrhage was observed in the main organs. Therefore, these results suggest thatthe formulated nanostructures have great potential for cancer therapies.

INTEGRATING NANOSCALE ZERO-VALENT IRON AND TITANIUM DIOXIDE FOR NUTRIENT REMOVAL IN STORMWATER SYSTEMS

NI-BIN CHANG,FAHIM HOSSAIN,LEI ZHAI,KUEN-SONG LIN,MARTY WANIELISTA 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2008 NANO Vol.3 No.4

Nutrients, such as nitrate, nitrite, and phosphorus, are common contaminants in many aquatic systems in the United States. Ammonia and nitrate are both regulated by the drinking water standards in the US primarily because excess levels of nitrate might cause methemoglobinemia. Phosphorus might become sources of the eutrophication problems associated with toxic algae in the freshwater bodies. Toxic algal blooms can cause severe acute and chronic public health problems. Chemical reduction of nitrate by using zero-valent iron started as early as 1964, and considerable research reports relating to this technology to nanomaterial were extensively reported in 1990s making the use of nanoscale zero-valent iron (NZVI) particles for nitrate removal become one of the most popular technologies in this field. The purpose of the present study was to examine the potential of integrating green sorption media, such as sawdust, limestone, tire crumb, and sand/silt, with two types of nanoparticles, including NZVI and Titanium Dioxide (TiO₂), for nitrate removal in an engineering process. The study consists of running packed bed column tests followed by the addition of NZVI and TiO₂ to improve nitrate and phosphorus removal efficiency. Preliminary results in this paper show that the potential and advanced study may support the creation of design criteria of stormwater and groundwater treatment systems for water reuse in the future.