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  1. Fulltext Di-n-butyl-bis-[N-(2-meth-oxy-eth-yl)-N-methyl-dithio-carbamato-κ2S,S']tin(IV): crystal structure and Hirshfeld surface analysis
    Mohamad R, Awang N, Kamaludin NF, Jotani MM, Tiekink ER
    Acta Crystallogr E Crystallogr Commun, 2017 Feb 01;73(Pt 2):260-265.
    PMID: 28217355 DOI: 10.1107/S2056989017001098
    The complete mol-ecule of the title compound, [Sn(C4H9)2(C5H10NOS2)2], is generated by a crystallographic mirror plane, with the SnIV atom and the two inner methyl-ene C atoms of the butyl ligands lying on the mirror plane; statistical disorder is noted in the two terminal ethyl groups, which deviate from mirror symmetry. The di-thio-carbamate ligand coordinates to the metal atom in an asymmetric mode with the resulting C2S4 donor set defining a skew trapezoidal bipyramidal geometry; the n-butyl groups are disposed to lie over the longer Sn-S bonds. Supra-molecular chains aligned along the a-axis direction and sustained by methyl-ene-C-H⋯S(weakly coordinating) inter-actions feature in the mol-ecular packing. A Hirshfeld surface analysis reveals the dominance of H⋯H contacts in the crystal.
  2. Fulltext Crystal structures and Hirshfeld surface analyses of bis-[N,N-bis-(2-meth-oxy-eth-yl)di-thio-carbamato-κ2S,S']di-n-butyl-tin(IV) and [N-(2-meth-oxy-eth-yl)-N-methyl-dithio-carbamato-κ2S,S']tri-phenyl-tin(IV)
    Mohamad R, Awang N, Kamaludin NF, Jotani MM, Tiekink ERT
    Acta Crystallogr E Crystallogr Commun, 2018 Mar 01;74(Pt 3):302-308.
    PMID: 29765711 DOI: 10.1107/S2056989018001901
    The crystal and mol-ecular structures of the two title organotin di-thio-carbamate compounds, [Sn(C4H9)2(C7H14NO2S2)2], (I), and [Sn(C6H5)3(C5H10NOS2)], (II), are described. Both structures feature asymmetrically bound di-thio-carbamate ligands leading to a skew-trapezoidal bipyramidal geometry for the metal atom in (I) and a distorted tetra-hedral geometry in (II). The complete mol-ecule of (I) is generated by a crystallographic twofold axis (Sn site symmetry 2). In the crystal of (I), mol-ecules self-assemble into a supra-molecular array parallel to (10-1) via methyl-ene-C-H⋯O(meth-oxy) inter-actions. In the crystal of (II), supra-molecular dimers are formed via pairs of weak phenyl-C-H⋯π(phen-yl) contacts. In each of (I) and (II), the specified assemblies connect into a three-dimensional architecture without directional inter-actions between them. Hirshfeld surface analyses confirm the importance of H⋯H contacts in the mol-ecular packing of each of (I) and (II), and in the case of (I), highlight the importance of short meth-oxy-H⋯H(but-yl) contacts between layers.
  3. [N-Benzyl-N-(2-phenyl-eth-yl)di-thio-carbamato-κ(2)S,S']tri-phenyl-tin(IV) and [bis-(2-meth-oxy-eth-yl)di-thio-carbamato-κ(2)S,S']tri-phenyl-tin(IV): crystal structures and Hirshfeld surface analysis
    Mohamad R, Awang N, Kamaludin NF, Jotani MM, Tiekink ER
    Acta Crystallogr E Crystallogr Commun, 2016 Oct 1;72(Pt 10):1480-1487.
    PMID: 27746946
    The crystal and mol-ecular structures of two tri-phenyl-tin di-thio-carbamates, [Sn(C6H5)3(C16H16NS2)], (I), and [Sn(C6H5)3(C7H14NO2S2)], (II), are described. In (I), the di-thio-carbamate ligand coordinates the Sn(IV) atom in an asymmetric manner, leading to a highly distorted trigonal-bipyramidal coordination geometry defined by a C3S2 donor set with the weakly bound S atom approximately trans to one of the ipso-C atoms. A similar structure is found in (II), but the di-thio-carbamate ligand coordinates in an even more asymmetric fashion. The packing in (I) features supra-molecular chains along the c axis sustained by C-H⋯π inter-actions; chains pack with no directional inter-actions between them. In (II), supra-molecular layers are formed, similarly sustained by C-H⋯π inter-actions; these stack along the b axis. An analysis of the Hirshfeld surfaces for (I) and (II) confirms the presence of the C-H⋯π inter-actions but also reveals the overall dominance of H⋯H contacts in the respective crystals.
  4. Distinct coordination geometries in bis-[N,N-bis-(2-meth-oxy-eth-yl)di-thio-carbamato-κ(2) S,S']di-phenyltin(IV) and bis-[N-(2-meth-oxy-eth-yl)-N-methyl-dithio-carbamato-κ(2) S,S']di-phenyl-tin(IV): crystal structures and Hirshfeld surface analysis
    Mohamad R, Awang N, Jotani MM, Tiekink ER
    Acta Crystallogr E Crystallogr Commun, 2016 Aug 1;72(Pt 8):1130-7.
    PMID: 27536397 DOI: 10.1107/S2056989016011385
    The crystal and mol-ecular structures of two di-phenyl-tin bis-(di-thio-carbamate)s, [Sn(C6H5)2(C5H10NOS2)2], (I), and [Sn(C6H5)2(C7H14NO2S2)2], (II), are described. In (I), in which the metal atom lies on a twofold rotation axis, the di-thio-carbamate ligand coordinates with approximately equal Sn-S bond lengths and the ipso-C atoms of the Sn-bound phenyl groups occupy cis-positions in the resulting octa-hedral C2S4 donor set. A quite distinct coordination geometry is noted in (II), arising as a result of quite disparate Sn-S bond lengths. Here, the four S-donors define a trapezoidal plane with the ipso-C atoms lying over the weaker of the Sn-S bonds so that the C2S4 donor set defines a skewed trapezoidal bipyramid. The packing of (I) features supra-molecular layers in the ab plane sustained by methyl-ene-C-H⋯π(Sn-ar-yl) inter-actions; these stack along the c-axis direction with no specific inter-actions between them. In (II), supra-molecular chains along the b-axis direction are formed by methyl-ene-C-O(ether) inter-actions; these pack with no directional inter-actions between them. A Hirshfeld surface analysis was conducted on both (I) and (II) and revealed the dominance of H⋯H inter-actions contributing to the respective surfaces, i.e. >60% in each case, and other features consistent with the description of the mol-ecular packing above.
  5. Fulltext (N,N-Diiso-propyl-dithio-carbamato)tri-phenyl-tin(IV): crystal structure, Hirshfeld surface analysis and computational study
    Haezam FN, Awang N, Kamaludin NF, Jotani MM, Tiekink ERT
    Acta Crystallogr E Crystallogr Commun, 2019 Oct 01;75(Pt 10):1479-1485.
    PMID: 31636979 DOI: 10.1107/S2056989019012490
    The crystal and mol-ecular structures of the title triorganotin di-thio-carbamate, [Sn(C6H5)3(C7H14NS2)], are described. The mol-ecular geometry about the metal atom is highly distorted being based on a C3S tetra-hedron as the di-thio-carbamate ligand is asymmetrically chelating to the tin centre. The close approach of the second thione-S atom [Sn⋯S = 2.9264 (4) Å] is largely responsible for the distortion. The mol-ecular packing is almost devoid of directional inter-actions with only weak phenyl-C-H⋯C(phen-yl) inter-actions, leading to centrosymmetric dimeric aggregates, being noted. An analysis of the calculated Hirshfeld surface points to the significance of H⋯H contacts, which contribute 66.6% of all contacts to the surface, with C⋯H/H⋯C [26.8%] and S⋯H/H⋯H [6.6%] contacts making up the balance.
  6. Fulltext Crystal structures and Hirshfeld surface analyses of (N-hexyl-N-methyl-dithio-carbamato-κ2S,S')triphenyl-tin(IV) and [N-methyl-N-(2-phenyl-ethyl)-dithio-carbamato-κ2S,S']tri-phenyl-tin(IV)
    Mohamad R, Awang N, Kamaludin NF, Jotani MM, Tiekink ERT
    Acta Crystallogr E Crystallogr Commun, 2018 May 01;74(Pt 5):630-637.
    PMID: 29850080 DOI: 10.1107/S2056989018005133
    The crystal and mol-ecular structures of two tri-phenyl-tin di-thio-carbamate compounds, viz. [Sn(C6H5)3(C8H16NS2)], (I), and [Sn(C6H5)3(C10H12NS2)], (II), are described. The di-thio-carbamate ligand in each mol-ecule coordinates in an asymmetric fashion resulting in heavily distorted tetra-hedral C3S coordin-ation geometries for the Sn atoms, with the distortions traced to the close approach of the non-coordinating thione-S atom. The mol-ecular packing in both compounds features C-H⋯π(Sn-phen-yl) inter-actions. In (I), the donors are Sn-phenyl-C-H groups leading to centrosymmetric aggregates, while in (II), the donors are both Sn-phenyl-C-H and methyl-C-H groups leading to supra-molecular chains propagating along the b axis. The identified aggregates assemble into their respective crystals with no directional inter-actions between them. An analysis of the Hirshfeld surfaces show distinctive patterns, but an overwhelming predominance (>99% in each case) of H⋯H, C⋯H/H⋯C and S⋯H/H⋯S contacts on the respective Hirshfeld surface.
  7. Fulltext (N,N-Di-allyl-dithio-carbamato-κ2 S,S')tri-phenyltin(IV) and bis-(N,N-di-allyl-dithio-carbamato-κ2 S,S')di-phenyl-tin(IV): crystal structure, Hirshfeld surface analysis and computational study
    Haezam FN, Awang N, Kamaludin NF, Jotani MM, Tiekink ERT
    Acta Crystallogr E Crystallogr Commun, 2020 Feb 01;76(Pt 2):167-176.
    PMID: 32071741 DOI: 10.1107/S2056989020000122
    The crystal and mol-ecular structures of the title organotin di-thio-carbamate compounds, [Sn(C6H5)3(C7H10NS2)] (I) and [Sn(C6H5)2(C7H10NS2)2] (II), present very distinct tin atom coordination geometries. In (I), the di-thio-carbamate ligand is asymmetrically coordinating with the resulting C3S2 donor set defining a coordination geometry inter-mediate between square-pyramidal and trigonal-bipyramidal. In (II), two independent mol-ecules comprise the asymmetric unit, which differ in the conformations of the allyl substituents and in the relative orientations of the tin-bound phenyl rings. The di-thio-carbamate ligands in (II) coordinate in an asymmetric mode but the Sn-S bonds are more symmetric than observed in (I). The resulting C2S4 donor set approximates an octa-hedral coordination geometry with a cis-disposition of the ipso-carbon atoms and with the more tightly bound sulfur atoms approximately trans. The only directional inter-molecular contacts in the crystals of (I) and (II) are of the type phenyl-C-H⋯π(phen-yl) and vinyl-idene-C-H⋯π(phen-yl), respectively, with each leading to a supra-molecular chain propagating along the a-axis direction. The calculated Hirshfeld surfaces emphasize the importance of H⋯H contacts in the crystal of (I), i.e. contributing 62.2% to the overall surface. The only other two significant contacts also involve hydrogen, i.e. C⋯H/H⋯C (28.4%) and S⋯H/H⋯S (8.6%). Similar observations pertain to the individual mol-ecules of (II), which are clearly distinguishable in their surface contacts, with H⋯H being clearly dominant (59.9 and 64.9%, respectively) along with C⋯H/H⋯C (24.3 and 20.1%) and S⋯H/H⋯S (14.4 and 13.6%) contacts. The calculations of energies of inter-action suggest dispersive forces make a significant contribution to the stabilization of the crystals. The exception is for the C-H⋯π contacts in (II) where, in addition to the dispersive contribution, significant contributions are made by the electrostatic forces.
  8. Cellular and DNA Toxicity Study of Triphenyltin Ethyl Phenyl Dithiocarbamate and Triphenyltin Butyl Phenyl Dithiocarbamate on K562, Leukemia Cell Line
    Hamid A, Rajab NF, Charmagne Y, Awang N, Jufri NF, Rasli NR
    Anticancer Agents Med Chem, 2024;24(1):58-65.
    PMID: 37921147 DOI: 10.2174/0118715206266851231025054446
    INTRODUCTION: Continuous research for new effective drugs to treat cancer has improved our understanding on the mechanism of action of these drugs and paved new potential for their application in cancer treatments. In this study, organotin compounds known as triphenyltin ethyl phenyl dithiocarbamate and triphenyltin butyl phenyl dithiocarbamate were investigated for their toxicity on leukemia cell line (K562) and non-cancerous cell line (Chang liver cell and lung fibroblast, V79 cell).

    METHODS: MTT assay was performed to evaluate the cytotoxic effects of both compounds toward the cells after 24, 48 and 72 hours of exposure or treatment. The alkaline comet assay was conducted to determine the DNA damage on K562 cells after been exposed to both compounds for 30, 60 and 90 minutes.

    RESULTS: The IC50 values obtained from K562 cells ranged from 0.01 to 0.30 μM, whereas for both Chang liver cell and lung fibroblast V79 cell, the values ranged from 0.10 to 0.40 μM. For genotoxicity evaluation, the percentage of damaged DNA is measured as an average of tail moment, and was found to be within 1.20 to 2.20 A.U while the percentage of DNA intensity ranging from 1.50 to 3.50% indicating no genotoxic effects.

    CONCLUSION: Both compounds are cytotoxic toward leukemia cells and non-cancerous cells but do not exert their genotoxic effects towards leukemia cell.

  9. The Development of Organotin(IV) N-Ethyl-N-Benzyldithiocarbamate Complexes: A Study on Their Synthesis, Characterization, and Cytocidal Effects on A549 Cell Line
    Abd Aziz NA, Awang N, Kamaludin NF, Mohamad Anuar NN, Hamid A, Chan KM, et al.
    Anticancer Agents Med Chem, 2024 Apr 15.
    PMID: 38629375 DOI: 10.2174/0118715206309421240402093335
    BACKGROUND: Organotin(IV) complexes of dithiocarbamate are vital in medicinal chemistry, exhibiting potential in targeting cancer cells due to their unique properties that enhance targeted delivery. This study aimed to synthesize and characterize organotin(IV) N-ethyl-N-benzyldithiocarbamate complexes (ONBDCs) and evaluate their cytotoxicity against A549 cells, which are commonly used as a model for human lung cancer research.

    METHOD: The two ONBDC derivatives - ONBDC 1 (dimethyltin(IV) N-ethyl-N-benzyldithiocarbamate) and ONBDC 2 (triphenyltin(IV) N-ethyl-N-benzyldithiocarbamate) - were synthesized via the reaction of tin(IV) chloride with N-ethylbenzylamine in the presence of carbon disulfide. A range of analytical techniques, including elemental analysis, IR spectroscopy, NMR spectroscopy, UV-Vis spectrometry, TGA/DTA analysis, and X-ray crystallography, was conducted to characterize these compounds comprehensively. The cytotoxic effects of ONBDCs against A549 cells were evaluated using MTT assay.

    RESULTS: Both compounds were synthesized and characterized successfully via elemental and spectroscopies analysis. MTT assay revealed that ONBDC 2 demonstrated remarkable cytotoxicity towards A549 cells, with an IC50 value of 0.52 μM. Additionally, ONBDC 2 displayed significantly higher cytotoxic activity against the A549 cell line when compared to the commercially available chemotherapeutic agent cisplatin (IC50: 32 μM).

    CONCLUSION: Thus, it was shown that ONBDC 2 could have important anticancer properties and should be further explored as a top contender for creating improved and specialized cancer treatments.

  10. Persistence of cognitive deficits following paediatric head injury without professional rehabilitation in rural East Coast Malaysia
    Abdullah JM, Kumaraswamy N, Awang N, Ghazali MM, Abdullah MR
    Asian J Surg, 2005 Jul;28(3):163-7.
    PMID: 16024307
    To use data from a prospective, longitudinal study to determine whether psychomotor functions improve spontaneously during the first year following paediatric traumatic brain injury without modern rehabilitation facilities in a rural area of Malaysia.
  11. Composition of heavy metals and airborne fibers in the indoor environment of a building during renovation
    Latif MT, Baharudin NH, Velayutham P, Awang N, Hamdan H, Mohamad R, et al.
    Environ Monit Assess, 2011 Oct;181(1-4):479-89.
    PMID: 21181256 DOI: 10.1007/s10661-010-1843-3
    The renovation of a building will certainly affect the quality of air in the vicinity of where associated activities were undertaken, this includes the quality of air inside the building. Indoor air pollutants such as particulate matter, heavy metals, and fine fibers are likely to be emitted during renovation work. This study was conducted to determine the concentration of heavy metals, asbestos and suspended particulates in the Biology Building, at the Universiti Kebangsaan, Malaysia (UKM). Renovation activities were carried out widely in the laboratories which were located in this building. A low-volume sampler was used to collect suspended particulate matter of a diameter size less than 10 μm (PM₁₀) and an air sampling pump, fitted with a cellulose ester membrane filter, were used for asbestos sampling. Dust was collected using a small brush and scope. The concentration of heavy metals was determined through the use of inductively coupled plasma-mass spectroscopy and the fibers were counted through a phase contrast microscope. The concentrations of PM₁₀ recorded in the building during renovation action (ranging from 166 to 542 μg m⁻³) were higher than the value set by the Department of Safety and Health for respirable dust (150 μg m⁻³). Additionally, they were higher than the value of PM₁₀ recorded in indoor environments from other studies. The composition of heavy metals in PM₁₀ and indoor dust were found to be dominated by Zn and results also showed that the concentration of heavy metals in indoor dust and PM₁₀ in this study was higher than levels recorded in other similar studies. The asbestos concentration was 0.0038 ± 0.0011 fibers/cc. This was lower than the value set by the Malaysian Department of Occupational, Safety and Health (DOSH) regulations of 0.1 fibers/cc, but higher than the background value usually recorded in indoor environments. This study strongly suggests that renovation issues need to be considered seriously by relevant stakeholders within the university in order to ensure that the associated risks toward humans and indoor environment are eliminated, or where this is not feasible, minimized as far as possible.
  12. Wavelet-based time series model to improve the forecast accuracy of PM10 concentrations in Peninsular Malaysia
    Yong NK, Awang N
    Environ Monit Assess, 2019 Jan 11;191(2):64.
    PMID: 30635772 DOI: 10.1007/s10661-019-7209-6
    This study presents the use of a wavelet-based time series model to forecast the daily average particulate matter with an aerodynamic diameter of less than 10 μm (PM10) in Peninsular Malaysia. The highlight of this study is the use of a discrete wavelet transform (DWT) in order to improve the forecast accuracy. The DWT was applied to convert the highly variable PM10 series into more stable approximations and details sub-series, and the ARIMA-GARCH time series models were developed for each sub-series. Two different forecast periods, one was during normal days, while the other was during haze episodes, were designed to justify the usefulness of DWT. The models' performance was evaluated by four indices, namely root mean square error, mean absolute percentage error, probability of detection and false alarm rate. The results showed that the model incorporated with DWT yielded more accurate forecasts than the conventional method without DWT for both the forecast periods, and the improvement was more prominent for the period during the haze episodes.
  13. Multiple linear regression and regression with time series error models in forecasting PM10 concentrations in Peninsular Malaysia
    Ng KY, Awang N
    Environ Monit Assess, 2018 Jan 06;190(2):63.
    PMID: 29306973 DOI: 10.1007/s10661-017-6419-z
    Frequent haze occurrences in Malaysia have made the management of PM10 (particulate matter with aerodynamic less than 10 μm) pollution a critical task. This requires knowledge on factors associating with PM10 variation and good forecast of PM10 concentrations. Hence, this paper demonstrates the prediction of 1-day-ahead daily average PM10 concentrations based on predictor variables including meteorological parameters and gaseous pollutants. Three different models were built. They were multiple linear regression (MLR) model with lagged predictor variables (MLR1), MLR model with lagged predictor variables and PM10 concentrations (MLR2) and regression with time series error (RTSE) model. The findings revealed that humidity, temperature, wind speed, wind direction, carbon monoxide and ozone were the main factors explaining the PM10 variation in Peninsular Malaysia. Comparison among the three models showed that MLR2 model was on a same level with RTSE model in terms of forecasting accuracy, while MLR1 model was the worst.
  14. Histopathological changes in placenta and liver of pregnant rats administered with aqueous extract of Dioscorea hispida var. daemona (Roxb) Prain & Burkill
    Muhammad H, Maslan SF, Md Saad WM, Thani NSIA, Ibnu Rasid EN, Mahomoodally MF, et al.
    Food Chem Toxicol, 2019 Sep;131:110538.
    PMID: 31152790 DOI: 10.1016/j.fct.2019.05.046
    Dioscorea hispida var. daemona (Roxb) Prain & Burkill (DH), also known a tropical yam or intoxicating yam is a bitter wild tuber which is consumed as a staple food and traditionally used as a remedy in Malaysia. However, DH is also notorious for its intoxicating effects and there is currently a dearth of study of possible effects of DH on liver and placental tissues and hence its safe consumption warrants in-depth investigation. This study was therefore designed to investigate into the effect of DH on liver and placenta of pregnant rat via histopathological examination. Thirty pregnant Sprague-Dawley rats were randomly divided into five groups consisting of a control (distilled water) and four DH aqueous extract groups (250, 500, 1000 and 2000 mg/kg body weight). The extracts were administered via oral gavage daily throughout the study and animals were sacrificed on day 21. Paraffin-embedded, hematoxylin and eosin stained sections of placenta and liver were examined. Significant changes (p 
  15. Fulltext Cellular Basis of Organotin(IV) Derivatives as Anticancer Metallodrugs: A Review
    Syed Annuar SN, Kamaludin NF, Awang N, Chan KM
    Front Chem, 2021;9:657599.
    PMID: 34368075 DOI: 10.3389/fchem.2021.657599
    Organotin(IV) compounds have wide applications in industrial and agricultural fields owing to their ability to act as poly(vinyl chloride) stabilizers and catalytic agents as well as their medicinal properties. Moreover, organotin(IV) compounds may have applications as antitumor, anti-inflammatory, antifungal, or antimicrobial agents based on the observation of synergistic effects following the binding of their respective ligands, resulting in the enhancement of their biological activities. In this review, we describe the antiproliferative activities of organotin(IV) compounds in various human cancer cell lines based on different types of ligands. We also discuss the molecular mechanisms through which organotin(IV) compounds induce cell death via apoptosis through the mitochondrial intrinsic pathway. Finally, we present the mechanisms of cell cycle arrest induced by organotin(IV) compounds. Our report provides a basis for studies of the antitumor activities of organotin(IV) compounds and highlights the potential applications of these compounds as anticancer metallodrugs with low toxicity and few side effects.
  16. Gene Expression Profiling associated with Hepatoxicity in Pregnant Rats treated with Ubi Gadong (Dioscorea hispida) Extract
    Faradianna Lokman E, Muhammad H, Awang N, Hasyima Omar M, Mansor F, Saparuddin F
    Int J Biomed Sci, 2017 Mar;13(1):26-34.
    PMID: 28533734
    Dioscorea hispida (D.hispida) is the most well-known starchy tuber in Malaysia and called 'ubi gadong'. Despite concerns over toxicity effects, the tuber is known to possess therapeutic values due to the presence of bioactive compounds such as saponins. This study was performed to identify the changes in gene expression profiles associated with hepatoxicity in pregnant rat treated with D.hispida using RT² Profiler PCR Array. The identification of steroidal saponins from D.hispida was carried out by UHPLC/MS method. Treatment of D.hispida caused mortality when dosage above 2000 mg/kg b.w. was given to pregnant rats. The PCR array showed that several genes were significantly up and down-regulated upon treatment with D.hispida. Treatment of D.hispida at 2000 mg/kg b.w leads to significant upregulation of several genes such as Btg2, Gsr, L2hgdn, S100a8, Slc17a3, Bhmt, Cd68, Cyp1a2 whereas several genes were downregulated such as Abcb1a, Aldoa, Cdc14b, Icam1, Krt18, Hpn and Maob. The consumption of D.hispida extract when taken at lower dosage of 2000 mg/kg may not be harmful to rats. D.hispida extract given at the highest dosage to pregnant rats caused alterations of several genes categorized in different hepatotoxic group functions such as necrosis, cholestasis and phospholipodisis.
  17. Fulltext Determination of lead, cations, and anions concentration in indoor and outdoor air at the primary schools in Kuala Lumpur
    Awang N, Jamaluddin F
    J Environ Public Health, 2014;2014:408275.
    PMID: 25136371 DOI: 10.1155/2014/408275
    This study was carried out to determine the concentration of lead (Pb), anions, and cations at six primary schools located around Kuala Lumpur. Low volume sampler (MiniVol PM10) was used to collect the suspended particulates in indoor and outdoor air. Results showed that the concentration of Pb in indoor air was in the range of 5.18 ± 1.08 μg/g-7.01 ± 0.08 μg/g. All the concentrations of Pb in indoor air were higher than in outdoor air at all sampling stations. The concentrations of cations and anions were higher in outdoor air than in indoor air. The concentration of Ca(2+) (39.51 ± 5.01 mg/g-65.13 ± 9.42 mg/g) was the highest because the cation existed naturally in soil dusts, while the concentrations of NO3 (-) and SO4 (2-) were higher in outdoor air because there were more sources of exposure for anions in outdoor air, such as highly congested traffic and motor vehicles emissions. In comparison, the concentration of NO3 (-) (29.72 ± 0.31 μg/g-32.00 ± 0.75 μg/g) was slightly higher than SO4 (2-). The concentrations of most of the parameters in this study, such as Mg(2+), Ca(2+), NO3 (-), SO4 (2-), and Pb(2+), were higher in outdoor air than in indoor air at all sampling stations.
  18. Fulltext A review on the potential of photocatalysis in combatting SARS-CoV-2 in wastewater
    Nasir AM, Awang N, Hubadillah SK, Jaafar J, Othman MHD, Wan Salleh WN, et al.
    J Water Process Eng, 2021 Aug;42:102111.
    PMID: 35592059 DOI: 10.1016/j.jwpe.2021.102111
    Photocatalytic technology offers powerful virus disinfection in wastewater via oxidative capability with minimum harmful by-products generation. This review paper aims to provide state-of-the-art photocatalytic technology in battling transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in wastewater. Prior to that, the advantages and limitations of the existing conventional and advanced oxidation processes for virus disinfection in water systems were thoroughly examined. A wide spectrum of virus degradation by various photocatalysts was then considered to understand the potential mechanism for deactivating this deadly virus. The challenges and future perspectives were comprehensively discussed at the end of this review describing the limitations of current photocatalytic technology and suggesting a realistic outlook on advanced photocatalytic technology as a potential solution in dealing with similar upcoming pandemics. The major finding of this review including discovery of a vision on the possible photocatalytic approaches that have been proven to be outstanding against other viruses and subsequently combatting SARS-CoV-2 in wastewater. This review intends to deliver insightful information and discussion on the potential of photocatalysis in battling COVID-19 transmission through wastewater.
  19. Fulltext Organotin (IV) Dithiocarbamate Compounds as Anticancer Agents: A Review of Syntheses and Cytotoxicity Studies
    Abd Aziz NA, Awang N, Chan KM, Kamaludin NF, Mohamad Anuar NN
    Molecules, 2023 Aug 03;28(15).
    PMID: 37570810 DOI: 10.3390/molecules28155841
    Organotin (IV) dithiocarbamate has recently received attention as a therapeutic agent among organotin (IV) compounds. The individual properties of the organotin (IV) and dithiocarbamate moieties in the hybrid complex form a synergy of action that stimulates increased biological activity. Organotin (IV) components have been shown to play a crucial role in cytotoxicity. The biological effects of organotin compounds are believed to be influenced by the number of Sn-C bonds and the number and nature of alkyl or aryl substituents within the organotin structure. Ligands target and react with molecules while preventing unwanted changes in the biomolecules. Organotin (IV) dithiocarbamate compounds have also been shown to have a broad range of cellular, biochemical, and molecular effects, with their toxicity largely determined by their structure. Continuing the investigation of the cytotoxicity of organotin (IV) dithiocarbamates, this mini-review delves into the appropriate method for synthesis and discusses the elemental and spectroscopic analyses and potential cytotoxic effects of these compounds from articles published since 2010.
  20. Respiratory health status of workers that exposed to welding fumes at Lumut shipyard
    Ithnin A, Zubir A, Awang N, Mohamad Sulaiman NN
    Pak J Biol Sci, 2019 Jan;22(3):143-147.
    PMID: 30972984 DOI: 10.3923/pjbs.2019.143.147
    BACKGROUND AND OBJECTIVE: Welding fume exposure has led to the respiratory problems among welders including cough, phlegm, chest illnesses, nausea and fatigue. Inadequate ventilation during welding works causes the situation to worsen. Welding fumes can cause a decrease in lung function among welders. Chronic exposure will lead to other health effects especially COPD (Chronic Obstructive Pulmonary Disease). The objective of this study is to determine the exposure of welding fumes (Cd, Fe, Pb and Zn) towards respiratory health including lung function test (FEV1, FVC, FEV1/FVC, PEFR) of workers in Lumut shipyard, Perak.

    MATERIAL AND METHODS: This research study the relationship between exposures of welding fumes towards lung function test among workers in Lumut shipyard, Perak. Lung function test was measured by spirometry among 30 welders and 31 non-welders. The concentration welding fume exposure was measured using OSHA ID-121 method. Sociodemographic data, respiratory symptoms and smoking habit data was analyzed based on the ATS 1987 questionnaire.

    RESULTS: The mean concentration for Pb in welding fumes was 2.752 mg m-3 which is above 0.5 mg m-3 PEL-TWA. The FEV1 and FVC readings showed significant different between welders and non-welders (p = 0.001). Cough and phlegm symptoms showed significant different between welders and non-welders (p = 0.001). Welders had higher prevalence in smoking habit than the non-welders. Chest illnesses symptom showed an association with the smoking habit (p = 0.01).

    CONCLUSION: There is relationship between welding fumes exposure on lung function test of workers in Lumut shipyard. Pb in welding fumes has high concentration and exceeded PEL-TWA level. The FEV1 and FVC in welders are lower than non-welder due to the fumes exposure. Welders showed higher respiratory symptoms than non-welders. Smoking habit is a contributing factor towards respiratory problem.
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