Salicylate-based protic ionic liquids (PILs) were synthesised, characterised and assessed in this study for potential antioxidant in drug design. The synthesised PILs were known as 3-dimethylamino-1-propanol salicylate (3DMAPS) and 3-diethylamino-1propanol salicylate (3DEAPS). Proton nuclear magnetic resonance ( 1 HNMR), Fourier transformation infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) were used to characterise the synthesised PILs. Furthermore, the antioxidant activity of the synthesised PILs was determined using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical assay. Both 3DMAPS and 3DEAPS showed a good antioxidant activity compared to parent acid (salicylic acid) as these two compounds could scavenge 20% of DPPH free radical at a concentration of 66.76 0.09 M and 27.27 0.10 M, respectively.

An investigation was conducted on cabbage extract (Brassica oleracea) to observe its function as green antifouling agent in alkyd undercoat for mild steel in seawater. Cabbage extract shows 43.6% of inhibition efficiency towards Pseudomonas aeruginosa bacteria at 15.525 g/mL cabbage concentration. FTIR analysis shows the complexation between alkyd paint and cabbage extract where the peak in OH, C-H and C=O have shifted indicating the chain scission of the alkyd resin polymer backbone with cabbage extract. Weight gained analysis reveals that coated mild steel incorporated with cabbage extract had reduced the fouling attachment. However, weight gained value increases as the immersion period increases for all coated samples. Morphological profile of coated mild steel shows an attachment of fouling where prominent attachment can be observed on coated mild steel without cabbage extract.

The emergence of antibiotic resistance against bacterial strains has attracted great interest in the discovery and development of new antibacterial agents. Thiazole derivatives have been widely used in the biological as well as pharmacological fields and their efficiency as pharmaceutical drugs are well established. In this study, a series of thiazole derivatives were synthesized in reaction between 3-chloroacetyl acetone and ammonium thiocyanate followed by incorporating selected primary amines in one-pot synthesis manner. The compounds were structurally characterized by FTIR, 1H NMR, UV-Vis and GC-MS. Their antibacterial properties were screened using disc diffusion technique against Gram positive (B. cereus and S. epidermidis) as well as Gram negative (E.coli and P. aeruginosa) bacterial strains. The compound of T3 exhibited the most potent antibacterial activity. Molecular docking studies were also performed against Glucosamine-6-phosphate (GlcN-6-P) synthase which is known as the essential building block of most bacteria. According to the docking result, T3 exhibited the minimum binding energy of -7.09 kcal mol-1 as compared to T1 and T2 with -6.49 and 6.76 kcal mol-1,respectively which is in agreement with antibacterial result. The output of this preliminary study will contribute in structural enhancement in drug discovery.

Mesoporous silica is material that possesses the pore sizes between 2 nm to 50 nm which had expanded their applications rapidly.In this study, mesostructured SBA-15 was synthesized and characterized then the electrochemical behaviour being analysed to determine the current signal and the impedance of mesoporous silica carbon electrode.The material with pore sizes 5.5 nm was successfully synthesized by surfactant templating technique, using triblock copolymer pluronic (P123) as directing agent and tetraethyl orthosilicate (TEOS) as silica sources.The synthesized SBA-15 was characterized using X-ray diffraction (XRD), scanning electron microscope (SEM), nitrogen adsorption-desorption and infra-red (IR).Two different electrodes were fabricated which carbon paste electrode (CPE) and hybrid SBA-15 with carbon paste electrode (SBA-15/MCPE) and analysed using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS).The SBA-15/MCPE results better adsorption and enhanced the response signal to 30% and lower resistance compared to CPE with 179Ω and 187Ω respectively due to addition of meso-sites which improved the electron pathway This study demonstrates that mesoporous silica (SBA-15) can be considered as promising material in development of high performance, lightweight and flexible devices in electrochemistry.

Malachite green is widely used in the aquaculture, food, and textile industries.However, malachite green is carcinogenic, mutagenic, and teratogenic.Therefore, a chemical sensor was developed to detect malachite green in water samples.Screenprinted carbon electrode was coated with (p(AAm-co-EMA)/Ru(bpy) 3 2+/AgNWs to investigate its potential as a membrane for chemical sensor.The membrane was synthesized using the photopolymerization technique and characterized by fourier transform infrared (FTIR), 1 H nuclear magnetic resonance ( 1 H NMR), swelling test, field emission scanning electron microscopy/electron dispersive X-ray analysis (FESEM/EDX), thermogravimetric analysis (TGA), and cyclic voltammetry (CV).The peak of -CO in the FTIR spectra indicated that the copolymerization was successful.Furthermore, the NMR spectrum confirmed the FTIR result with the presence of peak at 4.2 ppm.Swelling test showed that p(AAm-co-EMA)/AgNWs had a lower swelling percentage than p(AAm-co-EMA) due to AgNWs filling the pores of the membrane, which can be seen in the cross section of the SEM micrograph.Thermal decomposition temperature of the membrane was around 400 °C.Cyclic voltammogram proved that the p(AAm-co-EMA)/Ru(bpy) 3 2+/ AgNWs film coated on screen-printed carbon electrode which acted as a working electrode was able to detect malachite green by showing anodic peak around 0.25 V and cathodic peak around -1.0 V.

The inclusion complexation behaviour of bisphenol A (BPA) into hydrophobic cavity of -cyclodextrin (-CD) was investigated by using 1 H NMR spectroscopy in deuterium oxide by varying the molar ratios between -CD and BPA from 1:0 to 1:2. The ideal molar ratio for the -CD:BPA complex was determined as 1:1. In addition, the inclusion of BPA into -CD produced significant changes in the chemical shifts of H5 and H3 protons, which were located inside the cavity of cyclodextrin. On the other hand, the H2, H4 and H6 protons that were located at the exterior surface of -CD did not result in any significant changes in the chemical shift, and thus confirmed the formation of the -CD:BPA inclusion complex. The observed chemical shifts of H5 and H3 protons, when BPA interacted with the -CD cavity, were utilised to determine the binding association constant (K a ) and maximum chemical shift difference ( max ). From the nonlinear calculation, the K a for H3 proton, i.e. 4.10 x 10 3 M -1 , was shown to be stronger than that of H5, i.e. 3.62 x 10 3 M -1 . However, the H5 proton gave a higher max than the H3 proton, which were 0.1412 ppm and 0.0573 ppm, respectively.

Determining the shooter is an important element during investigation of firearm related offences, particularly through the detection of gunshot residue (GSR) as forensic evidence on shooter's hand. However, such detection could be restrained if it is obstructed by the wearing of gloves by a shooter. Hence, it is worth investigating the presence of GSR on gloves, aiming to suggest an individual's contact with a weapon. In this study, Modified Griess Reagent (MGT) commonly available in forensic laboratory was utilised to screen GSR on individual gloves of different materials worn by a shooter during a shooting training session. The experimental results revealed that both the palm and back of gloves equally allows the detection of GSR by MGT (p = 0.083). No statistically significant association was evident between the types of gloves and positive indication of MGT (p = 0.122). The types of firearms, neither revolver nor semi-automatic pistol showed significant association with the detection of GSR on the gloves (p = 0.248). When two-hand shooting was performed, glove samples worn on left and right hands gave almost similar testing results (p = 0.626). Although the presence of GSR on a glove after a shooting could be relatively low, the study has demonstrated that applying MGT, a simple test could assist crime scene investigation in determining the presence of GSR, in cases when gloves were used.

This research was aimed to optimize hydrogen production from fruit waste, particularly on the effect of the substrate-toinoculum ratio (SIR).Production of hydrogen was carried out through dark fermentation process both in mesophilic (30 °C, 1 atm) and thermophilic (55 °C, 1 atm) condition.Fermentation was conducted at SIR value ranging from 0.800 to 174 VS substrate /g VS inoc .In mesophilic fermentation, the highest cumulative total gas yield was achieved at SIR value of 19 corresponding total gas yield of 113 ml STP/g VS (5%v of H 2 ).In thermophilic condition, the highest H 2 yield was obtained at SIR value of 0.800 VS substrate /g VS inoc with H 2 yield of 294 mL STP/g VS (50 -60%v of purity).It was noticed that the lower SIR value, the higher hydrogen yield.In summary, it is concluded that substrate-to-inoculum ratio (SIR) plays important role in dark fermentation process to produce renewable energy of hydrogen fuel.

The harmful algal bloom (HABs) phenomena affects human health, ecosystems, fishing, and tourism industries. In a single occasion, the loss due to HABs can reach thousands of Ringgit Malaysia. In this study, a chitosan-silica composite (RHA-CHi) was synthesized via sol-gel technique for the mitigation of Alexandrium tamiyavanichii, a toxic HAB species isolated from Malaysian waters. Rice husk ash silica was used as the silica precursor in the composite synthesis. The FT-IR spectroscopy suggests that the chitosan was covalently bonded with the surface silanol groups. Light microscope analysis showed that the algal cells were stuck on the surface of the composite and underwent lysis. The incorporation of chitosan decreased the surface negative charge of the silica, hence, increasing the electrostatic attraction between the cells and RHA-Chi. The removal efficiency of A. tamiyavanichii was 75% using 0.1 mg/mL of RHA-Chi in 2 hours, increasing to 85% after 24 hours. Reduced removal efficiency (16%) was observed using silica alone. The findings show that the chitosan-silica composite has high potential to be used in the mitigation of A. tamiyavanichii.

An ex-mining site has created an undesirable effect on the environment, such as the destruction of plants and contamination. Thus, this study was conducted to determine the natural radioactivity and heavy metal presence in the ex-mining site at Kolej University Islam Antarabangsa Selangor (KUIS) lake. Both parameters were measured using gamma spectrometry and inductively coupled plasma-mass spectrometry (ICP-MS). The results showed that the concentrations of 238 U (0.44 0.31 Bq/L), 232 Th (0.04 0.02 Bq/L), 226 Ra (0.19 0.11 Bq/L), and 40 K (0.62 0.37 Bq/L) in water samples were below the recommended values by the World Health Organization (WHO) for drinking water source, which implied the safe consumption of the water. However, the presence of 238 U, 232 Th, 226 Ra, and 40 K in sediment samples exceeded the limit proposed by UNSCEAR, with the radioactivity of 49.1 18.8 Bq/kg, 102.3 3.3 Bq/kg, 133.2 18.8 Bq/kg, and 297.1 25.7 Bq/kg, respectively. For heavy metal determination, zinc was found in the sediment with the highest concentration (17.34 15.79 mg/kg) compared to other heavy metals, while the concentration of arsenic was highest in water with 0.58 0.26 g/L. All hazard indices were found to be below the safety limit except for the gamma index of 1.6 0.7 Bq/kg and 104.1 48.4 nGy/h for the gamma dose rate.