Polyvinyl alcohol-grafted-multiwalled carbon nanotubes as a delivery system for curcumin in H2O2-induced damaged neuroblastoma SH-SY5Y cells

Treating neurodegenerative disease using Curcumin, a pigment from turmeric is found difficult due to its low bioavailability. To overcome this problem, polyvinyl alcohol multi-walled carbon nanotubes (PVA-MWCNT) was developed to improve its delivery and uptake by the brain cells. It was first prepared by oxidizing pristine MWCNT (p-MWCNT) in 3:1 sulfuric and nitric acid mixture. Three methods were employed to optimize production of oxidized MWCNT (ox-MWCNT); which is stirring and sonication for 2 and 6 hours. The selected ox-MWCNT with minimal structural damage was then functionalized with PVA via carbodiimide esterification, and confirmed by field-emission scanning electron microscopy (FESEM), Fourier transform infra-red (FTIR) spectroscopy, dispersion test and thermal gravimetric analysis (TGA). Next, Curcumin was loaded onto PVA-MWCNT, p-MWCNT and ox-MWCNT, and evaluated their adsorption capacity and behaviour using adsorption kinetics, isotherm and thermodynamic studies. Percentage of Curcumin desorbed from the MWCNT was analyzed in physiological buffers of pHs 7.4 and 5.5. Lastly, potential of Curcumin loaded on PVA-MWCNT (Cur-PVA-MWCNT) to protect neurons was screened in neuroblastoma SH-SY5Y cells, including other Cur-loaded MWCNT samples. The cells were pre-incubated with hydrogen peroxide (H2O2) at half the maximal inhibitory concentration (IC50) for 1 hour, before concurrent treatment of the samples. Cell survival was compared to controls treated with Curcumin-unloaded MWCNT, i.e. PVA-MWCNT, ox-MWCNT and p-MWCNT. From the results, MWCNT was oxidized with minimal structural damage using stirring method. The evidence of PVA grafting was confirmed through the presence of matrix polymer embedded on ox-MWCNT in FESEM, high stability in water, identification C=O stretching of ester group at 1736 cm-1 in FTIR and its stable structure compared to ox-MWCNT and p-MWCNT in TGA. PVA-MWCNT adsorbed Curcumin at only 5.1 mg/g, which follows the Freundlich isotherm model (physisorption), while the highest amount was loaded on ox-MWCNT at 714 mg/g that follows the Langmuir model (chemisorption). Although Curcumin adsorption on PVA-MWCNT was only at minimal amount, it showed the most efficient desorption occurred at pH 5.5 (25%) rather than pH 7.4 (3%) with sustained release over a 3-day incubation. This suggests Curcumin weak binding through physisorption to the PVAMWCNT facilitated its release at lower pH. Cur-PVA-MWCNT also protected SHSY5Y cells from H2O2-induced oxidative stress most significantly at 100 ng/ml, 1 μg/ml and 10 μg/ml compared to PVA-MWCNT. Cur-ox-MWCNT and Cur-p- MWCNT indicated no obvious difference as compared to their controls. The change in the cell environment after damage perhaps encouraged the pH to become acidic which may facilitate Curcumin release from PVA-MWCNT. Overall, PVA-MWCNT was considered promising for loading and the release of Curcumin. The efficacy of the system in in vitro cell lines was also enhanced, demonstrating it as a prospective carrier for Curcumin in the treatment of neurodegenerative disease

Catalyst-free crosslinking modification of nata-de- coco-based bacterial cellulose nanofibers using citric acid

Bacterial cellulose (BC) has gained research attention in materials science and biomedicine due to its fascinating properties. BCs' fiber collapse phenomenon (inability to reabsorb water after dehydration) is one of the drawbacks that limit its potentials. To overcome this, a catalyst-free thermal crosslinking reaction was employed to modify the BC using citric acid (CA) without compromising the biocompatibility. Properties evaluation of the modified BC (MBC) by FTIR, XRD, SEM/EDX, TGA, and Tensile analysis confirmed the fiber crosslinking and improvement of some properties that could be advantageous for various applications. The modified nanofiber seems to maintain its inherent crystallinity and thermal stability with an increased water absorption/swelling and tensile modulus. The resulting MBC reported here can be relevant for wound dressings and tissue scaffolding

Citric acid: a green cross-linker of biomaterials for biomedical application

The application of biomaterials in biomedicine currently suffers some drawbacks, such as inflammation and immunological responses due to mismatching and/or limited compatibility. Biomaterials that are cross-linked with citric acid (CA), also called citrate-based biomaterials (CBBs), have exhibited advanced in-vitro and in-vivo material properties that make them suitable for various biomedical applications. Tunable mechanical properties, biocompatibility, and biofunctionality are among other factors that make CBBs interesting in this field. To emphasize the safety and greenness nature of CA, in this review, we have highlighted the history, potential considerations of exploration, and a summarized stage-wise criterion for developing CBBs. We also discuss several points of view about the application of CA and CBBs in many different aspects of biomedicine, such as in tissue engineering, cancer therapy, and wound dressings

In vivo evaluation of oxidized multiwalled-carbon nanotubes-mediated hyperthermia treatment for breast cancer

Breast cancer is one of the most common types of cancer that contribute to high mortality worldwide. Hyperthermia (HT) was introduced as one of the alternative treatments to treat breast cancer but has major drawback of damaging normal adjacent cells. This study explores the integration effect of multiwalled-carbon nanotubes (MWCNTs) in combination with hyperthermia treatment for breast cancer therapy regimes. In this study, acid-functionalized MWCNTs (ox-MWCNTs) were prepared by acid washing methods using H2SO4/HNO3 (98%/68%) with the ratio of 3:1 (?/?) and characterized by colloidal dispersibility test, FTIR, TGA, XRD, FESEM and EDX analysis. EMT6 tumor-bearing mice were treated with ox-MWCNTs in combination with local HT at 43 °C. The tumor progression was monitored and the influence of immune response was evaluated. Results from this study demonstrated that mice from ox-MWCNTs in combination with local HT treatment group experienced complete tumor eradication, accompanied by a significant increase in median survival of the mice. Histological and immunohistochemical analysis of tumor tissues revealed that tumor treated with combined treatment underwent cell necrosis and there was a significant reduction of proliferating cells when compared to the untreated tumor. This observation is also accompanied with an increase in Hsp70 expression in tumor treated with HT. Flow cytometry analysis of the draining lymph nodes showed an increase in dendritic cells infiltration and maturation in mice treated with combined treatment. In addition, a significant increase of tumor-infiltrated CD8+ and CD4+ T cells along with macrophages and natural killer cells was observed in tumor treated with combined treatment. Altogether, results presented in this study suggested the potential of ox-MWCNTs-mediated HT as an anticancer therapeutic agent, hence might be beneficial in the future of breast cancer treatment

Al-Quran dan geografi

Geografi adalah satu cabang sains yang mengkaji tentang bumi. Cabang sains ini adalah subjek yang paling menarik kerana dapat memberikan jawapan yang kerapkali anda tanyakan kepada diri anda, misalannya, “Mengapakah hujan turun?” “Adakah semua batuan mempunyai galian?” “Mengapakah pokok tumbang boleh menyebabkan hakisan?” dan sebagainya. Pentingnya untuk manusia mempelajari ilmu geografi ini adalah untuk memahami persekitaran dengan lebih mendalam serta menilai sumber serta peluang yang terdapat dalamnya. Lebih terang dan jelas dalam al-Quran terdapat pengajaran ayat Allah S.W.T. yang diketengahkan tentang kejadian alam semesta yang begitu indah dan ajaib kejadiannya yang menunjukan tanda kebesaran Allah. Dengan memikir dan merenung maka manusia akan diilhamkan dengan ilmu pengetahuan, idea serta kepandaian yang menjadikan manusia dapat mentadbir alam ini mengikut acuan Allah S.W.T. berteraskan kepada syariat yang telah diturunkan. Dalam bidang geografi, terdapat dua aspek utama, iaitu Geografi Fizikal yang merangkumi bumi sebagai satu sistem, batuan, laut dan lautan, iklim, luluhawa, ekosistem, tumbuhan dan haiwan; dan Geografi Manusia yang merangkumi skop ekonomi, kebudayaan, politik, meterologi dan ekologi bumi yang dipengaruhi oleh kegiatan manusia. Antara contoh kegiatan yang dimaksudkan dalam Geografi Manusia adalah seperti pengangkutan, pertanian, perikanan, perlombongan, perikanan, pembalakan, penempatan, perusahaan, penempatan, pengangkutan dan perkhidmatan. Huraian dalam aspek Geografi Fizikal paling banyak yang disebutkan dalam al-Quran yang dikaji dan diteliti oleh manusia kejadian alam semesta, pembentukan dan pergerakan bumi, bentuk fizikal bumi serta fungsinya pada alam sejagat sehinggalah kejadian akhir alam semesta (Goh, 2010)

Students and school learning environment motivate success of Excellent Islamic Education Teachers (EIET)

This article aims to discuss the extrinsic factors that motivate the excellence of Excellent Islamic Education Teachers (EIET) through a case study. This study was conducted by interviews among the EIET, their colleagues, school principal and students at eight different secondary schools in Malaysia. All of the interviewed and observed data were processed, analyzed and organized using the N’Vivo Version 7.0 to develop theme and matrix table with regards to the extrinsic factors influencing the excellence of EIET. The study reveals that students and learning environment has been the major factors in encouraging the EIET success

Preliminary evaluation on the EMT6 breast tumor inhibitory activity of carbon nanotubes with hyperthermia

Breast cancer is considered one of the most dangerous types of cancer with a high mortality rate among women worldwide. Potential alternative treatments such as hyperthermia (HT) often associated with poor specific heat distribution within the tumor microenvironment, thus reducing its anticancer potential. Owing to the fact that CNTs possessed high thermal conductivity, which could provide a uniform heat distribution, this study aims at exploring the combined effect of CNTs and HT in managing breast tumors. In this study, multiwalled CNTs were functionalized by acid washing protocol and validated by characterization analysis. Female Balb/c mice were inoculated with EMT6 breast cancer cells and then were intratumorally injected once with MWCNTs before being subjected to HT treatment for 3 consecutive days. Tumor progression and survival curves of mice were monitored. Our results demonstrated a successful functionalization of MWCNTs throughout dispersion, FTIR, TGA, XRD and FESEM analysis. Moreover, the combined-treated tumor showed complete eradication and prolonged survival median. The histological data revealed that combined treatment induced significant tumor necrosis post-treatment. Altogether, results from this preliminary study suggested that functionalized CNTs in combination with HT demonstrated a promising effect in eliminating EMT6 breast tumor

Development of biodegradable bio-based composite for bone tissue engineering: synthesis, characterization and in vitro biocompatible evaluation

Several significant advancements in the field of bone regenerative medicine have been made in recent years. However, therapeutic options, such as bone grafts, have several drawbacks. There is a need to develop an adequate bone substitute. As a result, significant bone defects/injuries pose a severe challenge for orthopaedic and reconstructive bone tissue. We synthesized polymeric composite material from arabinoxylan (ARX), β-glucan (BG), nano-hydroxyapatite (nHAp), graphene oxide (GO), acrylic acid (AAc) through free radical polymerization and porous scaffold fabricated using the freezedrying technique. These fabricated porous scaffolds were then coated with chitosan solution to enhance their biological activities. The complex structure of BG, nHAp, GO was studied through various characterization and biological assays. The structural, morphological, wetting and mechanical analyses were determined using FT-IR, XRD, XPS, SEM/EXD, water contact angle and UTM. The swelling (aqueous and PBS media) and degradation (PBS media) observed their behavior in contact with body fluid. The biological activities were conducted against mouse pre-osteoblast cell lines. The result found that BGH3 has desirable morphological, structural with optimum swelling, degradation, and mechanical behavior. It was also found to be cytocompatible against MC3T3-E1 cell lines. The obtained results confirmed that the fabricated polymeric scaffolds would be a potential bone substitute to regenerate defective bone with different loading bearing applications for bone tissue engineering

Transdermal delivery of crocin using bacterial nanocellulose membrane

This work reports the inclusion of crocin (an active agent of saffron) into bacterial nanocellulose (BNC) membrane for transdermal drug delivery. The BNC showed good uptake of the crocin based on the swelling studies and vibrational peaks of the FTIR spectra. Surface morphology of the crocin loaded BNC showed that the fibrous nano feature was still intact with no fiber damages. The crocin release via direct dissolution showed typical burst release. Franz diffusion test revealed stable and prolong drug permeation. Partition coefficient of the BNC-crocin via mice epidermal skin diffusion was found to be 2.44×10−4 cm−2 min−1 with the average mass flux of 0.53 cm−2 min−1. This facile method of utilizing BNC for the carrier of crocin can be useful for administrating other water soluble active compound. Thus BNC opens up choices for the delivery of crocin for medicinal purposes