Programme: Industrial Chemistry

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Here you will find works strictly related to Industrial Chemistry.

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Natural and anthropogenic biomarkers in recent dated sediment cores from Refome Lake, SE Nigeria: environmental implications
(Environ Earth Sci, 2016) Oyo-Ita, Orok Esu; Oyo-Ita, Inyang Okon; Sam, Edidiong Sunday; Ikip, Ekpo Offem; Ugim, Ugim Samuel
Natural and anthropogenic biomarkers characteristics of two recent sediment cores collected toward the shoreline and center of Refome Lake (RS and RC; 30 cm long), southeastern Nigeria, were investigated in order to reconstruct past environmental conditions and asses humans-induced changes on the local ecosystem over the last century. Results from sediment bulk properties such as total organic carbon (TOC; 0.12–0.54%; mean— 0.26 ± 0.9%), total nitrogen (TN; 0.01–0.05%; mean— 0.03 ± 0.7%) and total inorganic carbon (TIC; 0.03–0.37%; mean—0.14 ± 1.0%) contents as well as TOC/TN (5–25; mean—11.55 ± 1.4) suggested slightly higher contribution from allochthonous over autochthonous organic matter (OM), lowered by low primary production and the characteristic Niger Delta sheltered basin morphology predominated by sandy lithology. Evaluation of molecular proxies such as carbon preference index (CPI(C24–C35); 1.23–1.74: mean—1.58 ± 0.4), carbon maxima (Cmax—17, 19, 26, 27, 29), long-chain/short-chain hydrocarbons (LHC/SH-C; 0.77–2.25, mean—1.52 ± 0.3) and Paq, (0.21–0.61, mean–0.45 ± 0.3) as well as C29/C27 (0.89–2.67; mean—1.53 ± 0.2) indicated an admixture slightly predominated by microbial OM (algae/bacteria) in the most recent top layer (RC1, 0–5 cm) of RC core and slightly more enhanced terrestrially derived OM in the middle layer (RS4, 15–20 cm) of RS core. The later sediment layer deposited at ca. 1947–1964 coincided with the period of greater wash-in of land-derived OM (associated with tree logging/forest clearing for foot path extension and farmland preparation authorized by the European settlers) occasioned by intense rainfall. The occurrence of gammacerane and 18a-oleanane in low levels in the lower and upper layers revealed trace contamination by petroleum hydrocarbons imported into the Nigerian economy prior to independence in 1960 and utilization of Niger Delta oil after 1960 following departure of the colonial masters (the British), respectively.
Source Characterization and Historical Trend of Sedimentary PAHs from Refome Lake, South–South Nigeria
(Aquat Geochem, 2017) Oyo-Ita, Inyang O.; Oyo-Ita, Orok E.; Ikip, Ekpo O.; Sam, Edidiong S.; Ugim, Ugim S.
Polycyclic aromatic hydrocarbons (PAHs) released from diverse sources passing through water column carry information into the sediment where they can be used to assess the environmental status of an ecosystem over specified geologic time frame. The vertical distributions of PAHs in two recent sediment cores (RS and RC, 30 cm long) from Refome Lake, South–South Nigeria,were investigated using gas chromatography–mass spectrometry in order to evaluate their sources and historical trends of deposition over the last ca. century. The total PAHs (TPAHs—sum of parent and retene) concentrations ranged from 66.99 ng/g dry weight (dw) at the middle layer ofRCcore (RC3 10–15 cm) to 182.24 ng/gdwat the near-bottomlayer of RS core (RS5 20–25 cm) with amean of 102.21 ± 24.32 ng/g. The elevated TPAH level at the near-bottom layer of the RS core, corresponding to geologic time-frame ca. 1930–1947, coincided with the period of inhabitation of the European settlers along the lake’s catchments when utilization of coal and/or coal products for domestic/recreational activity was at its peak. A decline in TPAH levels up-cores thereafter reflected the periods of gradual evacuation of inhabitants of the lake area hinterland following the departure of theWhite after the Nigerian independence in 1960. Evaluation of PAH category according to ring size coupled with data from specific molecular ratios revealed inputs dominated by wood/coal combustion with a moderate contribution from petrochemical/liquid fossil fuel exhaust emissions and a minor diagenetic sources. Principal component analysis result not only distinctively separated RS fromRCcore samples but also revealed that the RS samples weremore impacted by wood/coal combustion emissions than the RC, while liquid fossil fuel exhaust emission dominated the RC over the RS samples. Although short-range eolian transport did play a role in the delivery of PAHs to the lake, localization of source contamination was more important.
Determination Of Nutritional Potential Of Cymbopogon Citratus (D.C.) Staph By Atomic Absorption Spectroscopy And Its Health Benefits
(International Journal of Innovative Research and Advanced Studies (IJIRAS) Volume 5 Issue 3,, 2018) Umoh, Emmanuel Michael; Sam, Edidiong Sunday; Udoh, I. I.
Lemon grass (Cymbopogon citratus) was processed for analyses. They were sorted and chopped into bits. They were sundried for 12hrs, oven dried for 24hrs at 60oC and pulverized. Digestion was carried out according to AOAC 2000 and analysed for P, Mg, K, Na, Se, B, Co, Fe, Zn, Mn, Cu and Ca contents using Unicam 939/959 Atomic Absorption Spectrophotometer. Out of these twelve “botanical based minerals”, the most abundant was potassium followed by magnesium, phosphorus and calcium the least being boron. Most nutritional problems in Nigeria experienced by the vulnerable groups - the children and the elderly are due to mineral deficiencies in unwholesome or processed foods. Minerals usually obtained from synthetic mineral supplements are inadequate for the rural population due to high cost of procurement and at times adulteration. Most of them are toxic to susceptible individuals. Lemon grass is very effective in „Ajurvedic‟ medicine because of the “botanical based minerals” and bioactive compounds therefore taken in adequate quantities will help in the improvement of general health.
The Recycling of Sawdust Waste into Particleboard Using Starch- Based Modified Adhesive
(Communication in Physical Sciences, 6(1), 2020) Umoh, Emmanuel Michael; Sam, Edidiong Sunday
The challenges associated with the management of wastes from the cassava processing and timber industries necessitated an investigation into the possibility of implementing recycling approach to produced particle board from these wastes. Particleboards were produced from wood saw dust using various compositions of modified starch adhesives. The product obtained were evaluated for density, moisture content, hardness, flexural strength, water absorption and thickness swelling. The results obtained indicated that the density ranged from 753 to 798 kg/m3, moisture content ranged from 14.87 to 16.67 %, hardness ranged from 9.02 to 9.31 N/nm2, flexural strength ranged from 1.31 to 1.45 MPa, water absorption capacity at 24 h ranged from 1.06 to 9.31 %, thickness swelling ranged from 4.55 to 4.78%. The products were in conformity with IS 3087 (2005) and ANSI A 208.1 (1993) standards and could go for medium density particleboard.
VAPOUR GENERATION CHEMILUMINESCENCE DETECTION SYSTEM FOR DETERMINATION OF DIMETHYLSULPHONIOPROPIONATE AND DIMETHYLSULPHIDE IN TROPICAL SEAWATER
(Rasayan J. Chem., 13(1), 44-50(2020), 2020) Adedapo, A. E.; Benson, N. U.; Williams, A. B.,; Toda, K.
The vapour generation – chemiluminescence (VG-CL) detection system that was designed for this research was used for the measurement of dimethylsulphide (DMS) and its precursor dimethylsulphoniopropionate (DMSP). The present study attempted the development of a highly sensitive, portable and cost-effective detection system based on vapour generation and chemiluminescence for a pilot assessment and determination of DMSP and DMS concentrations in the Gulf of Guinea. The Elegushi Beach and Nigerian Institute of Oceanography and Marine Research (NIOMR) which are parts of the Atlantic Ocean were chosen as designated locations for this study. The average concentrations of DMSP and DMS in the surface seawater at the two locations ranged from 12.4 ± 0.2 to 26.5 ± 0.5 nM, 2.1± 0.0 to 40.9 ± 1.6 nM and 9.7 ± 0.4 to 44.9 ± 0.2 nM, 0 to 35.6 ± 2.3 nM, respectively. This study serves as a baseline measurement of the concentrations of DMS and DMSP in the tropical Atlantic Ocean (Lagos).
A censorious appraisal of the oil well acidizing corrosion inhibitors
(Journal of Petroleum Science and Engineering 215, 2022) Solomon, Moses M.; Uzoma, Ifeanyi E.; Olugbuyiro, Joseph A.O.; Ademosun, Olabisi T.
Well acidizing is a common stimulation technique for maximizing the output of oil reservoirs. It helps to overcome the low permeability of wellbore by creating new flow channels or enlarging old ones. Corrosion challenge is encountered during the process since tubings are metallic. Corrosion inhibitors are the defence mechanism used in mitigating corrosion problem during acidizing. This review has identified and grouped acidizing corrosion inhibitors into organic-, and polymer-based. The performance of these inhibitors at temperatures of ≥60 ◦C and acid concentration of ≥15 wt% is considered. It is noted that greater percentage of studies revolve round the 60 ◦C. Above 100 ◦C, the number of scientific articles decreased considerably. Four classes of intensifiers for acidizing corrosion inhibitors have been identified: formic acid, potassium iodide, copper iodide, and antimony chloride. Their chemistries have been discussed. The research gaps identified include (i) scanty information on acidizing inhibitors at temperatures ≥150 ◦C, (ii) limited information on natural polymers and plant biomaterials as acidizing inhibitors, (iii) scanty information on the mechanism of inhibition at temperatures ≥150 ◦C, and (v) limited information on the composition of corrosion products under acidizing conditions. Thus, recommendations for future researches have been given.
Photocatalytic Activity of Green Mixed Matrix Membranes for Degradation of Anionic Dye
(Green Chemistry for Sustainable Water Purification, 2022-12-27) Oladipo, Gabriel Opeoluwa; Alayande, Samson Oluwagbemiga; Ogunyinka, Opeyemi O; Akinsiku, Anuoluwa Abimbola; Akinsipo-Oyelaja, Oyesolape Basirat; Ofudje, Edwin Andrew; Bolarinwa, Hakeem S.; Akinlabi, Akinola Kehinde; Msagati, Titus. A.M.
Anionic dye is a notable constituent of textile effluent, which renders water unsafe for human and animal use. A notable approach to mitigating effluent is the use of membranes. In this study, a mixed matrix technique was adopted for the preparation of composite membranes. The composite membranes consist of crumb rubber filled with nanoparticles, respectively. The membranes were characterized by Fourier transform spectroscopy, scanning electron microscopy coupled with energy dispersive x-ray, thermogravimetric analyser, and drop shape analyzer. The photocatalytic activities of the mixed matrix membranes were investigated with anionic dye in the UV/visible region. Photocatalytic activity of composite membranes showed high degradation with an apparent rate constant. This study presents a rubber-based membrane for wastewater treatment.
Stable carbon isotope and n‑alkane distributions in sediment cores from saline and freshwater Gabu lakes, southeast Nigeria: environmental implications
(Environmental Earth Sciences, 2023) Oyo‑Ita, Inyang O.; Sam, Edidiong S.; Oyo‑Ita, Orok E.; Arnold, Elliott T.; Inyang, David O.; Werne, Josef P.
Studies on the utilization of molecular and isotopic proxies for the characterization of organic matter (OM) sources and environmental conditions in lakes have been well-documented globally. Nevertheless, inland lacustrine salt basins remain less well-studied, particularly in tropical sub-Saharan Africa. In this study, we quantified OM sources and evaluated the effects of salt deposit and barite mining on the distribution of n -alkanes in saline and freshwater Gabu lakes sediment cores, southeast Nigeria using elemental, bulk carbon isotope ratios and biomarker distributions. Our results indicate a system inundated with comparable proportions of vascular plant leaf waxes (mean = 56.6%) and submerged/floating macrophytes (mean = 41.1%) with minor contribution from algae/photosynthetic bacteria (mean = 2.3%). The scenario indicates a shallow water system that predominantly preserved long chain n-alkanes derived from vascular plant leaf waxes and macrophytes. The capacity of macrophyte to biosynthesize long chain n-alkanes most likely reflects adaptation of these organisms to partial exposure to the atmosphere. The occurrence in moderate abundance of C17 and C19 n-alkanes and the near absence of other low molecular weight (LMW) n-alkanes in the saline lake was linked to the effect of salt stress. The absence of LMW n-alkanes in freshwater lake may be associated with slow barite hydrolysis likely to cause acidification. Our results have demonstrated that long chain n -alkanes of terrestrial and submerged/floating macrophyte origins are better preserved under conditions of low salinity and acidification in inland shallow lakes than those derived from algae/bacteria
Amino-functionalised mesoporous silica nanoparticles for the delivery of isoniazid and its metal complexes
(Materials Chemistry and Physics Volume 326, 2024) Tella, Josephine Oluwagbemisola; Adekoya, Joseph Adeyemi; Ajanaku, Kolawole Oluseyi; Banerjee, Rajkumar; Patra, Chitta Ranjan; Pavuluri, Srinivasu; Sreedhar, Bojja
The effective delivery of poor water-soluble anti-tubercular drugs such as isoniazid to their target sites is a major factor that has made it difficult for tuberculosis to be eradicated. Isoniazid derivatives and nano-particulate drug delivery systems are explored as one way to address this limitation. This study investigated the use of amino functionalised mesoporous silica nanoparticles (MCM-41) as nano-carriers for the delivery of isoniazid-based metal complexes, Cu–INH and Fe–INH. The Sol-gel method was used to synthesise the nano-carriers, which produced a series of well-ordered nano-carriers. Their physicochemical properties were modified through surface functionalisation with amino groups via post-grafting synthesis. The isoniazid based metal complexes were incorporated into the nano-carriers using rotary evaporation. The nano-carriers were characterised using X-ray diffraction (XRD), Zeta potential, Fourier Transmission Infra-red (FT-IR), Brunaeur Emmett Teller (BET), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Thermogravimetric analysis (TGA). These characterisation techniques confirmed the successful surface functionalisation of the nano-carriers with amino groups and their encapsulation with INH, Cu–INH and Fe–INH. The amino-functionalised nano-carriers were observed to have the highest drug loading capacities and entrapment efficiencies within the range of 7.85%–19.31 % and 39.26%–96.53 %, respectively. The release rates of INH, Cu–INH, and Fe–INH from the nano-carriers were also studied in Phosphate Buffer Solution (PBS) with pH of 7.4 and 5.4 using ultraviolet–visible spectroscopy. The cumulative release rates of INH, Cu–INH, and Fe–INH from their nano-carriers depended on their release media's textural properties and environmental conditions. Amino functionalised nano-carriers had high release rates, with A-MCM 41+Cu–INH having the highest of 37.09 % in PBS at 5.4 after 24 h. The cumulative data obtained was fitted into Zero order, First order, Hixson Crowell, Higuchi, Korsmeyer Peppas and Weibull models. The Hixson Crowell, Korsmeyer-Peppas, and Weibull models fitted well with correlation coefficients (R2) of 0.9813, 0.9769 and 0.9802, respectively, for MCM-41+INH in PBS of pH 5.4.
Biosynthesis, characterization, and antimicrobial study of zinc oxide nanoparticles using Adonida merrilli leaf extract
(International Conference on Science, Engineering and Business for Driving Sustainable Development Goals, 2024) Owoeye, Taiwo Felicia; Bamisaye, Abayomi; Adekoya, Joseph Adeyemi; Afolalu, Sunday A.; Monye, Stella Isioma; Ojo, Augustine Oluwatyin
The utilization of plant-mediated methods to synthesize metal oxide nanoparticles (NPs) is becoming increasingly popular due to its simplicity, low cost, and environmental friendliness. Adonida merrilli leaf extracts in aqueous form were used for the production of nanoparticles of zinc oxide (ZnO). scanning electron microscope with energy dispersive X-ray (SEM-EDX), Fourier transform infrared spectrometer (FTIR), X-ray diffractometry (XRD), and UV-Vis spectrophotometer were accustomed to analyze the ZnO nanoparticles. The antibacterial effects of the ZnO NPs was examined on pathogens such Salmonella, Candida, Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa.XRD indicate spherical crystalline nanoparticles with an average particle size of 73.82 nm. Zinc oxide nanoparticle absorption wavenumber at 715 cm-1 was seen in the FTIR, and EDX chemical mapping confirms the elemental composition of zinc and oxygen. For Candida, Salmonella, Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus measured Zones of Inhibition (ZI) values are 30.00, 36.00, 32.00, 40.00, and 36.00 mm, and the measured Minimum Inhibitory Concentration (MIC) values are 7.81, 1.95, 7.81, 1.95, and 3.90 mg/mL, respectively. The results of this investigation, as shown by the MIC and ZI values, point to the possible use of Adonida merrilli extract in the synthesis of highly crystalline Zinc oxide nanoparticles (ZnONPs) as an alternative medication.
Environmental Radioactivity Monitoring and Radiological Impact Assessment of Agbara Industrial Area, Ogun State, Nigeria
(Polytechnica, 2024) Usikalu, Mojisola Rachael; Orosun, Muyiwa Michael; Akinwumi, Akinpelu; Babarimisa, Idowu Olaegbe; Arijaje, Theophilus Emuobor; Mohammed, Adamu Usman
Abstract This study assessed the naturally occurring radioactivity of 40K, 238U, and 232Th, which pose a significant threat to human health, particularly when their concentrations exceed the threshold. Background radiation levels were measured at two specific locations, Access Bank and Market areas, across a total of forty (40) sample points. The measurements were taken using a calibrated RS125 Gamma Spectrometer (a portable NaI [Tl] detector) designed in Canada, in conjunction with a global positioning system (GPS) to accurately record the research coordinates within the Agbara industrial area, Ogun State, Nigeria. The mean activity concentrations of the primordial radionuclides were 177.87 Bqkg-1, 20.01 Bqkg 1, and 52.90 Bqkg-1 for 40K, 238U, and 232Th, respectively. More so, the in-situ measured dose rate (DR) ranges between 12.18 nGyh-1 (Access Bank area) and 97.95 nGyh-1 (Market area), with an average value of 47.22 nGyh-1. The average measured and estimated absorbed dose rates were within the safe limit of 57 nGyh-1 provided by UNSCEAR. However, the measured dose rates exceeded the recommended limit in ten locations, while measured activity for thorium exceeded the world average value for over half of the study locations. Although all estimated radiological parameters were within recommended threshold values, suggesting the low risk of exposure to higher levels of ionising radiation in most locations in the Agbara industrial area, there is a potential cancer risk for individuals who have resided in the area for 70 years or more due to long-term exposure to ionising radiation.
Nutritional Indices, Phytochemistry, and the In Vitro Antioxidant Activity of Carrot Fortified Tomato Concentrate
(Wiley Journal of Food Quality, 2024) Ademosun, Olabisi Theresa; Adebayo, Abiodun Humphrey; Ajanaku, Kolawole Oluseyi
Researchers are constantly looking at the development of functional foods from local materials that o.er both nutritional and therapeutic potentials. e study investigated the proximate composition, antioxidant capacity, and phytochemical pro0le of di.erent compositions of formulations produced from tomato and carrot. e plant materials were sourced locally, dried to a uniform weight, and milled using a mechanical blender. Nutritional indices, viz., proximate analysis, were analyzed using a standard protocol. e phytocompounds present in the formulations and their in vitro antioxidant activities were analyzed using spectrophotometric methods. e results for proximate composition showed low moisture content in formulations (0.44 ± 0.015–0.54 ± 0.021%). e protein content of the formulations (16.51 ± 0.217–17.94 ± 0.134%) was signi0cantly higher than that of carrot alone (8.41 ± 0.154%). Similarly, the crude fat was elevated in the formulations (0.31 ± 0.008–1.63 ± 0.017%) compared to tomato alone (0.10 ± 0.399). However, these values were lower than the values obtained for carrot alone (8.72 ± 0.009%). e energy value for the formulations ranged from 87.01 to 93.30 kcal, which was low compared to carrot alone (136.89 kcal). Phytochemical screening showed the presence of terpenoids, cardiac glycosides, saponins, phenols,
Whole-exome sequencing of Nigerian benign prostatic hyperplasia reveals increased alterations in apoptotic pathways
(The Prostate April 2024 Vol 84 No. 5, 2024-01-04) Kaninjing, Ernest T.; Adeniji, Kayode A.; Jibrin, Paul; Obafunwa, John O.; Path, FMC; Path, FRC; Ogo, Chidiebere N.; Mohammed, Faruk; Popoola, Ademola; Fatiregun, Omolara A.; Oluwole, Olabode P.; Thorpe, Roland J.; Karanam, Balasubramanyam; Elhussin, Isra; Ambs, Stefan; Tang, Wei; Davis, Melissa; Polak, Paz; Campbell, Moray J.; Brignole, Kathryn R.; Rotimi, Solomon O.; Dean-Colomb, Windy; Odedina, Folake T.; Yates, Clayton
Background Through whole-exome sequencing of 60 formalin-fixed paraffin-embedded Nigerian (NGRn) benign prostatic hyperplasia (BPH) samples, we identified germline and somatic alterations in apoptotic pathways impacting BPH development and progression. Prostate enlargement is a common occurrence in male aging; however, this enlargement can lead to lower urinary tract symptoms that negatively impact quality of life. This impact is disproportionately present in men of African ancestry. BPH pathophysiology is poorly understood and studies examining non-European populations are lacking. Methods In this study, NGRn BPH, normal prostate, and prostate cancer (PCa) tumor samples were sequenced and compared to characterize genetic alterations in NGRn BPH. Results Two hundred and two nonbenign, ClinVar-annotated germline variants were present in NGRn BPH samples. Six genes [BRCA1 (92%), HSD3B1 (85%), TP53 (37%), PMS2 (23%), BARD1 (20%), and BRCA2 (17%)] were altered in at least 10% of samples; however, compared to NGRn normal and tumor, the frequency of alterations in BPH samples showed no significant differences at the gene or variant level. BRCA2_rs11571831 and TP53_rs1042522 germline alterations had a statistically significant co-occurrence interaction in BPH samples. In at least two BPH samples, 173 genes harbored somatic variants known to be clinically actionable. Three genes (COL18A1, KIF16B, and LRP1) showed a statistically significant (p < 0.05) higher frequency in BPH. NGRn BPH also had five gene pairs (PKD1/KIAA0100, PKHD1/PKD1, DNAH9/LRP1B, NWD1/DCHS2, and TCERG1/LMTK2) with statistically significant co-occurring interactions. Two hundred and seventynine genes contained novel somatic variants in NGRn BPH. Three genes (CABP1, FKBP1C, and RP11-595B24.2) had a statistically significant (p < 0.05) higher alteration frequency in NGRn BPH and three were significantly higher in NGRn tumor (CACNA1A, DMKN, and CACNA2D2). Pairwise Fisher's exact tests showed 14 gene pairs with statistically significant (p < 0.05) interactions and four interactions approaching significance (p < 0.10). Mutational patterns in NGRn BPH were similar to COSMIC (Catalog of Somatic Mutations in Cancer) signatures associated with aging and dysfunctional DNA damage repair. Conclusions NGRn BPH contained significant germline alteration interactions (BRCA2_rs11571831 and TP53_rs1042522) and increased somatic alteration frequencies
Interaction of black carbon surface mass with meteorological variables and spatial pattern across the 36 states of tropical Nigeria
(Remote Sensing Applications: Society and Environment Volume 35, 2024-08) Etchie, Ayotunde Titilayo
Black carbon (BC) has been linked to cardio-pulmonary diseases and lung cancer. It is also the second largest contributor to climate change, after carbon dioxide (CO2 ), Effective mitigation of BC is of much benefits, but it requires detailed knowledge of its spatial distribution, as well as the influence of local meteorology on the spread of the pollutant. Many countries in sub-Sahara Africa including Nigeria, lack data on BC level. There is also limited information on meteorological impact on BC spatial distribution. This study therefore assessed the spatial and temporal distribution of BC across the 36 states of Nigeria and the influence of meteorology on the pollutant spread. Data on BC surface mass (BCMASS) and seven meteorological variables (air temperature, relative humidity, rainfall, wind speed, planetary boundary layer height (PBLH), atmospheric pressure and wind direction) were obtained from Modern Era Retrospective analysis for Research (MERRA-2). Spatial distribution of BCSMASS across 36 states of Nigeria, and interaction with meteorology was studied using correlation analyses, Bayesian ridge regression with marginal maximum likelihood estimation, and a Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model. There was significant (p < 0.05) variation in BCSMASS across the states. The meteorological variables, except wind direction, significantly influenced BCSMASS and they accounted for 63% of the variation. Five-day backward trajectory modelled for each month of the year revealed that northern Nigeria is majorly under the influence of the dry and dusty tropical continental wind, and this could partially account for the lower BCSMASS concentration in the region, compared to southern Nigeria. Based on population-weighted exposure, states in southern Nigeria, especially the south-eastern part, should be prioritized in planning mitigation, for effective climate action.
Advances in nanoparticles as drug delivery systems: A review
(Scientific African, 2025) Akomolafe, Oluwatobi Abayomi; Akinsiku, Anuoluwa Abimbola
The use of nanoparticles in the pharmaceutical sector as drug carriers is rapidly growing, with many benefits over conventional drug delivery procedures. These nanoscale carriers are composed of biodegradable biocompatible materials, delivering therapeutic agents to the target with precise control and mitigating unwanted side effects. Despite numerous reports, many research gaps remain; thus, opportunities to improve the specificity and effectiveness of nanoparticle-based drug delivery for various illnesses, such as cancer, cardiovascular disease, infectious diseases, and central nervous system (CNS) disorders, are identified. The advances in nanoparticle-based drug delivery and their tremendous potential for revolutionising how drugs are delivered to treat disease are discussed. This review provides an overview of the various types of nanoparticles, including lipid-based, polymeric, natural polymers, and inorganic nanoparticles, which are being developed with their unique physical and chemical characteristics. It also reveals the strategies employed to enhance the targeting efficacy and stability of these nanoscale carriers in nanomedicine. The advantages, mechanisms, future direction, and drawbacks of each nanoparticle-based drug delivery system in target therapy and personalised medicine are well reviewed. Thus, addressing the identified gaps will be crucial for the clinical translation of nanoparticle-based therapeutics.
Antimicrobial and cytotoxicity evaluation of Annona muricata-based silver-cobalt nanoparticles on WEHI 164 cell line
(Results in Chemistry, 2025) Akinsiku, Anuoluwa Abimbola; Odaudu, Ruth Opiotu; Ejilude, Oluwaseun
The harsh chemicals in conventionally fabricated metal nanoparticles have limited their applications for biomedical purposes. As part of green and sustainable chemistry in this study, an aqueous extract of indigenous Annona muricata was a reductant in preparing silver‑cobalt nanoparticles (Ag Co NPs) for therapeutic appli cation. The reaction progress and rate of formation of nanoparticles were monitored with a UV–visible spec trophotometer. The functional groups, structural morphology, and elemental composition of the Ag Co NPs were confirmed using FTIR, SEM, TEM, and EDX techniques, respectively. This study evaluated the cytotoxicity potential of 21.38± 8.0 nm Ag–– Co NPs on the WEHI 164 cell line for the first time, using an MTT assay and the antimicrobial potential of Ag Co NPs against six microorganisms. The characteristic wavelength of absorption was observed between 400 and 450 nm. The antimicrobial test showed evident growth inhibition by Ag Co NPs on P. aeruginosa, Candida albicans and Aspergillus niger. The in vitro cytotoxicity evaluation on the WEHI 164 cell line indicated that the Ag–– Co NPs were cytotoxic at an IC 50 dosage of 84 concentration-dependent. Hence, the Annona muricata synthesised Ag μ g/mL, and the cytotoxic potential was Co NPs are potential pharmaceutical drug candidates.
Structure-based Design of Coumarin Moieties as Sustainable Inhibitors of Diabetes Mellitus Type 2
(2025) Opebiyi, O. T.; Oduselu, G.O.; Ogunnupebi, T. A.; Elebiju, O. F.; Adekoya, Joseph Adeyemi; Ajani, O. O.
The search for novel and more potent antidiabetic agents globally is due to the increase in insulin resistance, and more type 2 diabetes patients become susceptible to secondary compilations. Many pharmacologically active compounds are organic, mostly heterocyclic compounds, accounting for about 85% of Food and Drug Administration (FDA)-approved drugs. An example of a heterocyclic compound is coumarin, a benzopyrone group containing oxygen heteroatoms. Coumarin has been reported to possess several pharmacological properties, and combining coumarin with other compounds has made coumarin more potent. Computer-aided techniques have helped improve the design of potential drug candidates. Using computer-aided techniques, coumarin moieties were investigated for antidiabetic activities for future drug design. Coumarin template was used to search for ligand library on PubChem, an open chemistry database at the National Institutes of Health (NIH); 1653 compounds were downloaded with acarbose and metformin in SDF format, 1632 compounds, acarbose and metformin were successfully prepared, and then docked against human pancreatic alpha-amylase (Protein Data Bank- PDB ID: 4GQR) with Autodock vina. The qualitative structural assessment of the best hits from this molecular docking of a ligand library, acarbose and metformin was done. The functional groups present in this best hits, acarbose and metformin were used to generate 15 novel coumarin derivatives. The designed compounds were also docked against 4GQR, and their chemical absorption, distribution, metabolism, excretion, and toxicity (ADMET) studies were conducted. It was observed that 11 of the designed compounds had the lowest binding affinity than the co-crystalized ligand of 4GQR. The best hits compounds from the docking studies were 2g, 2f, 1a and 3e, and the ADMET studies predicted that compounds 1a, 3b, 3c and 3a had better pharmacokinetic and toxicity profiles. This promising result suggests that the designed compounds, particularly 1a, 3b, 3c and 3a, have the potential to be further optimized, synthesized and developed as potent antidiabetic agents, offering a hopeful future for diabetes treatment.
Recent developments strategies in high entropy modified lithium-rich layered oxides cathode for lithium-ion batteries
(ECS Meeting Abstracts, Volume MA2025-01,, 2025) Ajayi, Samuel O.; Ehi-Eromosele, Cyril; Liu, Xinying; Mathe, Mahlanyane Kenneth
LiNi0.5Mn0.2Co0.2O2 (NMC532) is a widely used cathode material in commercial lithium-ion batteries; however, it suffers from capacity degradation and poor rate performance. In this study, sol-gel combustion synthesis (SCS) with a controlled fuel-to-oxidizer ratio (fuel stoichiometric (FS) and fuel-rich (FR) compositions, the fuel-lean (FL)) respectively, was employed to improve the structural and electrochemical performance of the NMC532 cathode. The fuel-to-oxidizer ratio was found to significantly impact the exothermicity of the combustion reaction, which subsequently influenced the morphology, crystal structure, and electrochemical performance of the synthesized NMC532 material. The FL composition produced a well-defined layered structure, the largest crystallite size, and the lowest degree of cation mixing compared to the FS and FR compositions. The FL cell exhibited an initial discharge capacity of 180 mAh/g and the highest capacity retention of 92.2% when cycled at 0.1 C within a voltage range of 2.5–4.4 V. Additionally, it demonstrated superior rate capability, delivering capacities of 180, 178, 175, and 173 mAh/g at current densities of 1 C, 3 C, 5 C, and 10 C, respectively, within a voltage range of 3.0–4.6 V. The electrochemical impedance spectroscopy (EIS) measurements confirmed that the FL cell had the lowest polarization and impedance. The superior electrochemical performance of the FL cathode was ascribed to its improved structural properties.
Improving cycling performance and high rate capability of LiNi0.5 Mn0.3 Co0.2 O2 cathode materials by sol-gel combustion synthesis
(Journal of Physics and Chemistry of Solids, Volume 196, 2025-01) Ehi-Eromosele, Cyril O.; Liu, Xinying; Mathe, Mkhulu K.
The layered LiNi0.5 Mn0.2 Co0.2 O2 (NMC532) material displays capacity loss and poor rate performance even though it is a widely used cathode in commercial Li-ion batteries (LIBs). In this work, the structural and electrochemical performance of the NMC532 cathode were optimized using the fuel-to-oxidizer ratio assisted sol-gel combustion synthesis (SCS). It was shown that the fuel-to-oxidizer ratio markedly influenced the exothermicity of the combustion reaction which affected the crystal structure, morphology, and electrochemical performance of the final NCM532 materials. The fuel lean (FL) composition produced NMC532 cathode materials with the biggest crystallite and particle sizes, less cation mixing degree and better layered structure compared with the fuel stoichiometric (FS) and fuel rich (FR) compositions. The FL cell presented an initial discharge capacity of 180 mAh g−1 and the highest capacity retention of 92.2 % when it was cycled at 0.1 C between 2.5 and 4.4 V. Also, the FL cell displayed exceptional rate capability with the average capacities reaching 180, 178, 175, and 173 mAh/g at current densities of 1 C, 3 C, 5 C, and 10 C, respectively between 3.0 and 4.6 V. The EIS tests and dQ/dV plots showed that the FL cell both had the least impedance and polarization. The superior electrochemical performance of the FL material was ascribed to its optimized structural properties. Furthermore, the electrochemical results also show the influence of voltage window and current density on the performance of the NMC532 cathode materials.
Recent developments strategies in high entropy modified lithium-rich layered oxides cathode for lithium-ion batteries
(Inorganic Chemistry Communications, 2025-02) Ajayi, Samuel O.; Dolla, Tarekegn H.; Bello, Ismaila T; Liu, Xinying; Makgwane, Peter R.; Mathe, Mkhulu K.; Ehi-Eromosele, Cyril O.
Lithium-rich layered oxides (LRLOs) are of intense interest and are regarded as one of the best cathodes for next-generation Lithium-Ion batteries (LIBs). LRLOs are favored due to the low cost of production, high energy densities, voltage, and specific capacity. LRLOs suffer from irreversible capacity loss, poor rate capability, voltage, and capacity fade, which in turn limit their full practical applications and commercialization. Therefore, strategies such as surface coating, surface treatment, composition optimization, and elemental doping have been explored to enhance the structural and electrochemical performance of LRLO. Nevertheless, high entropy (multiple elements) doping has proven to be a very effective strategy due to its simplicity and expansion of LRLO lattice interplanar spacing without damaging their original structure. It is worth noting that there has been little research work on high entropy strategies for modifying LRLO cathode. Thus, the aim of this review is current update on high entropy strategies for modifying LRLO cathode materials.