Tlou Thatayotlhe Mosekiemang

@ub.bw

Lecturer Department of Environmental Science
University of Botswana

Tlou Thatayotlhe Mosekiemang


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https://researchid.co/mosekiemang

EDUCATION

BSc Applied Chemistry RMIT University, MSc Environmental Science University of Botswana, PhD Chemistry Stellenbosch University

RESEARCH, TEACHING, or OTHER INTERESTS

Analytical Chemistry, Environmental Chemistry, Pollution, Water Science and Technology
7

Scopus Publications

238

Scholar Citations

5

Scholar h-index

5

Scholar i10-index

Scopus Publications

  • A Global Perspective of Mercury and Cadmium in Agricultural Soils and Cereal Grains
    Babra Moyo, Victor Ntuli, Bienvenu Gael Fouda-Mbanga, Tlou Mosekiemang
    Global Perspectives of Toxic Metals in Bio Environs Volume 1 Environmental Impact Ecotoxicology Health Concerns and Modelling, 2025
  • A facile lyophilisation-based sample preparation approach for the determination of selected wastewater-borne antiretroviral drugs and metabolites by SFC-MS/MS
    Tlou Mosekiemang, Sithandile Ngxangxa, Matlhogonolo Kelepile
    Arabian Journal of Chemistry, 2024
    The presence of pharmaceuticals in aquatic ecosystems is at the centre-stage of research after the realization that wastewater treatment processes are generally ineffective in the removal of these entities in wastewater given the high likelihood of effluent reuse after disposal. In addition, the continued efforts to scout for new and emerging aquatic contaminants has until recently elicited proliferation of numerous analytical methods for the determination of various (un)known contaminants, since emphasis is now placed in the development of environmentally benign approaches. Herein, we propose and discuss a novel and relatively eco-friendly analytical method based on lyophilization for sample preparation and SFC-MS/MS for the determination of eight (8) antiretroviral drugs (ARVDs) and three (3) metabolites in wastewater samples. This method proved useful in the improvement for the recoveries of lamivudine (3TC) and emtricitabine (FTC) by up to 99% compared to as low as 23% with solid phase extraction (SPE) method. Indeed, previous literature reports has reported poor recoveries for the polar ARVDs, especially on reversed phase (RP) SPE. In contrast, lyophilization promoted matrix effects as evidenced by ion suppression of up to 50% experienced on late eluting compounds. Despite this, lyophilization-SFC-MS/MS method was successfully validated for the quantification of all target analytes, partial exceptions were for ritonavir metabolite (RTVM) which could not be quantified using lyophilization possibly due to lyophilization-induced losses. Generally, the obtained data has proved that lyophilization is an alternative to SPE and SFC is a suitable alternative to LC.
  • Comparison of internal standard and standard additions calibration procedures for the determination of selected heavy metals in treated municipal effluent by MP-AES
    Keabetswe Sewawa, Tlou Mosekiemang, Kebonyethata Dintwe, Nashaat Mazrui, Sithandile Ngxangxa, Oagile Dikinya, Kwenga Sichilongo, Bontle Mbongwe, Julius Atlhopheng
    Results in Chemistry, 2023
    We compared the internal standard calibration and standard additions calibration methods in the determination of Cd, Cr, Fe, Mn, Pb and Zn in municipal effluent using microwave-induced plasma atomic emission spectrometer. Comparison was based on validation parameters such as linearities, linear ranges, limits of detection (LOD), precisions and recoveries obtained using both calibration methods. Both methods gave good linearities applicable to a simple linear regression data fitting. Severe loss of linearity was observed at levels beyond 3 mg/L particularly for Zn. Considering this, the compromise linear range for all target analytes was established at LOD–3 mg/L. While the LODs for the target analytes were sufficiently low for both methods, the internal standard method was found to be more sensitive compared to standard additions method. Thus, the optimal linear ranges were accurately established at 0.24–0.96 mg/L for the internal standard and 1.10–1.96 mg/L for the standard additions method. Analyte recoveries including for the certified reference material averaged ∼ 100%. Therefore, all target analytes with the exception of Cd, which was possibly below the method detection limit were confidently detected and accurately quantified in municipal effluent samples. Overall, the excellent quantitative data obtained in this study inferred a high level of confidence in the developed methods in that they differed by less than 10%. Indisputably, the performance of the MP-AES operated in internal standard- and standard additions modes have proved to be a sufficiently sensitive technique especially for heavy metals occurring at sub-ppm levels.
  • Investigating groundwater and surface water interactions using stable isotopes and hydrochemistry in the Notwane River Catchment, South East Botswana.
    L.T. Modie, P.K. Kenabatho, M. Stephens, T. Mosekiemang
    Journal of Hydrology Regional Studies, 2022
    The ephemeral Notwane River Catchment (NRC) is situated in semi-arid Southeast (SE) Botswana. It is part of the Ramotswa Transboundary Dolomitic Aquifer (RTBDA) in the Limpopo basin, shared by Botswana and South Africa. Stable isotopic composition of deuterium (2H) and oxygen (18O) of the water molecule and water chemistry of groundwater and surface water (GW and SW) including rainfall samples were used to assess GW-SW interactions in the NRC. In addition, the seasonal effects on GW-SW interactions were also evaluated. As such, sample collection excursions were timed to coincide with the wet- and dry seasons, respectively. GW and SW were found to have similar chemical characteristics. The major ions in both water types were Ca2+ and HCO-3 in both the dry- and wet season. There was a clear inverse relationship between ground relief and/or elevation and the concentration of chloride ions (mg/L) and electrical conductivity (µS/cm). That is, higher concentrations of chlorine were measured downstream compared to upstream and vice versa. The same trend was manifested for EC levels. Overall, the data indicated the existence of some highly active groundwater recharge sites along the Notwane River, that may be responsible for the aquifer recharge during above-normal rainfall events. In addition, the data revealed albeit inconclusively that GW-SW interactions in the NRC are likely to be influenced by an interplay of several factors such as: (a) the difference in water levels between the river and the adjacent groundwater table (b) the hydrogeology and location of the river channel because geologic formations such as faults and karsts play a critical role in GW-SW interactions. Karsts are known to support groundwater recharge which is different from the nearby semi-arid Kalahari region where recharge is driven by soil profile.
  • Ultra-high pressure liquid chromatography coupled to travelling wave ion mobility-time of flight mass spectrometry for the screening of pharmaceutical metabolites in wastewater samples: Application to antiretrovirals
    Tlou T. Mosekiemang, Maria A. Stander, André de Villiers
    Journal of Chromatography A, 2021
  • Simultaneous quantification of commonly prescribed antiretroviral drugs and their selected metabolites in aqueous environmental samples by direct injection and solid phase extraction liquid chromatography - tandem mass spectrometry
    Tlou T. Mosekiemang, Maria A. Stander, André de Villiers
    Chemosphere, 2019
  • Efficiency of chelating agents in retaining sludge-borne heavy metals in intensively applied agricultural soils
    T. Mosekiemang, O. Dikinya
    International Journal of Environmental Science and Technology, 2012

RECENT SCHOLAR PUBLICATIONS

  • A Global Perspective of Mercury and Cadmium in Agricultural Soils and Cereal Grains
    B Moyo, V Ntuli, BG Fouda-Mbanga, T Mosekiemang
    Global Perspectives of Toxic Metals in Bio Environs: Volume 1: Environmental … , 2025
    2025.0
    Citations: 1
  • A facile lyophilisation-based sample preparation approach for the determination of selected wastewater-borne antiretroviral drugs and metabolites by SFC-MS/MS
    T Mosekiemang, S Ngxangxa, M Kelepile
    Arabian Journal of Chemistry 17 (9), 105924 , 2024
    2024.0
    Citations: 4
  • Occurrences of Cadmium, Arsenic, Lead, and Mercury in Potable
    B Mbongwe, PT Odirile, B Letsholo, B Lesetedi, R Tapera, L Mmualefe, ...
    Poisoning: Prevention, Diagnosis, Treatment and Poison Repurposing, 43 , 2024
    2024.0
  • Household Water Access and Water, Sanitation and Hygiene (WASH) Services in Rural Botswana, a Case of Molepolole Village
    TI Sebobi, M Kelepile, H Garekae, TT Mosekiemang
    Sanitation 8 (1), 24-24 , 2024
    2024.0
  • Occurrences of cadmium, arsenic, Lead, and mercury in potable water in greater Gaborone, Botswana: Implications for Public Health
    B Mbongwe, PT Odirile, B Letsholo, B Lesetedi, R Tapera, L Mmualefe, ...
    Poisoning-Prevention, Diagnosis, Treatment and Poison Repurposing , 2023
    2023.0
    Citations: 2
  • Comparison of internal standard and standard additions calibration procedures for the determination of selected heavy metals in treated municipal effluent by MP-AES
    K Sewawa, T Mosekiemang, K Dintwe, N Mazrui, S Ngxangxa, O Dikinya, ...
    Results in Chemistry 5, 100907 , 2023
    2023.0
    Citations: 11
  • Investigating groundwater and surface water interactions using stable isotopes and hydrochemistry in the Notwane River Catchment, South East Botswana.
    LT Modie, PK Kenabatho, M Stephens, T Mosekiemang
    Journal of Hydrology: Regional Studies 40, 101014 , 2022
    2022.0
    Citations: 57
  • Ultra-high pressure liquid chromatography coupled to travelling wave ion mobility-time of flight mass spectrometry for the screening of pharmaceutical metabolites in wastewater …
    TT Mosekiemang, MA Stander, A de Villiers
    Journal of Chromatography A 1660, 462650 , 2021
    2021.0
    Citations: 18
  • Novel analytical methods for the determination of antiretroviral drugs and their metabolites in environmental water samples.
    TT Mosekiemang
    Stellenbosch: Stellenbosch University , 2021
    2021.0
    Citations: 2
  • Simultaneous quantification of commonly prescribed antiretroviral drugs and their selected metabolites in aqueous environmental samples by direct injection and solid phase …
    TT Mosekiemang, MA Stander, A de Villiers
    Chemosphere 220, 983-992 , 2019
    2019.0
    Citations: 124
  • Sorption of heavy metals by Ferralic-Arenosol and Vertic-Luvisol: a comparative isothermal study
    T Mosekiemang, O Dikinya, E Toteng
    Environment and Pollution (Published by Canadian Center of Science and … , 2014
    2014.0
    Citations: 1
  • Efficiency of chelating agents in retaining sludge-borne heavy metals in intensively applied agricultural soils
    T Mosekiemang, O Dikinya
    International Journal of Environmental Science and Technology 9 (1), 129-134 , 2012
    2012.0
    Citations: 16
  • Yield and yield component compensation in pearl millet [Pennisetum glaucum L.] in Botswana
    SK Karikari, T Mosekiemang
    CROP RESEARCH-HISAR- 23 (1), 27-33 , 2002
    2002.0
    Citations: 2
  • Results in Chemistry
    K Sewawa, T Mosekiemang, K Dintwe, N Mazrui, S Ngxangxa, O Dikinya, ...

MOST CITED SCHOLAR PUBLICATIONS

  • Simultaneous quantification of commonly prescribed antiretroviral drugs and their selected metabolites in aqueous environmental samples by direct injection and solid phase …
    TT Mosekiemang, MA Stander, A de Villiers
    Chemosphere 220, 983-992 , 2019
    2019.0
    Citations: 124
  • Investigating groundwater and surface water interactions using stable isotopes and hydrochemistry in the Notwane River Catchment, South East Botswana.
    LT Modie, PK Kenabatho, M Stephens, T Mosekiemang
    Journal of Hydrology: Regional Studies 40, 101014 , 2022
    2022.0
    Citations: 57
  • Ultra-high pressure liquid chromatography coupled to travelling wave ion mobility-time of flight mass spectrometry for the screening of pharmaceutical metabolites in wastewater …
    TT Mosekiemang, MA Stander, A de Villiers
    Journal of Chromatography A 1660, 462650 , 2021
    2021.0
    Citations: 18
  • Efficiency of chelating agents in retaining sludge-borne heavy metals in intensively applied agricultural soils
    T Mosekiemang, O Dikinya
    International Journal of Environmental Science and Technology 9 (1), 129-134 , 2012
    2012.0
    Citations: 16
  • Comparison of internal standard and standard additions calibration procedures for the determination of selected heavy metals in treated municipal effluent by MP-AES
    K Sewawa, T Mosekiemang, K Dintwe, N Mazrui, S Ngxangxa, O Dikinya, ...
    Results in Chemistry 5, 100907 , 2023
    2023.0
    Citations: 11
  • A facile lyophilisation-based sample preparation approach for the determination of selected wastewater-borne antiretroviral drugs and metabolites by SFC-MS/MS
    T Mosekiemang, S Ngxangxa, M Kelepile
    Arabian Journal of Chemistry 17 (9), 105924 , 2024
    2024.0
    Citations: 4
  • Occurrences of cadmium, arsenic, Lead, and mercury in potable water in greater Gaborone, Botswana: Implications for Public Health
    B Mbongwe, PT Odirile, B Letsholo, B Lesetedi, R Tapera, L Mmualefe, ...
    Poisoning-Prevention, Diagnosis, Treatment and Poison Repurposing , 2023
    2023.0
    Citations: 2
  • Novel analytical methods for the determination of antiretroviral drugs and their metabolites in environmental water samples.
    TT Mosekiemang
    Stellenbosch: Stellenbosch University , 2021
    2021.0
    Citations: 2
  • Yield and yield component compensation in pearl millet [Pennisetum glaucum L.] in Botswana
    SK Karikari, T Mosekiemang
    CROP RESEARCH-HISAR- 23 (1), 27-33 , 2002
    2002.0
    Citations: 2
  • A Global Perspective of Mercury and Cadmium in Agricultural Soils and Cereal Grains
    B Moyo, V Ntuli, BG Fouda-Mbanga, T Mosekiemang
    Global Perspectives of Toxic Metals in Bio Environs: Volume 1: Environmental … , 2025
    2025.0
    Citations: 1
  • Sorption of heavy metals by Ferralic-Arenosol and Vertic-Luvisol: a comparative isothermal study
    T Mosekiemang, O Dikinya, E Toteng
    Environment and Pollution (Published by Canadian Center of Science and … , 2014
    2014.0
    Citations: 1
  • Occurrences of Cadmium, Arsenic, Lead, and Mercury in Potable
    B Mbongwe, PT Odirile, B Letsholo, B Lesetedi, R Tapera, L Mmualefe, ...
    Poisoning: Prevention, Diagnosis, Treatment and Poison Repurposing, 43 , 2024
    2024.0
  • Household Water Access and Water, Sanitation and Hygiene (WASH) Services in Rural Botswana, a Case of Molepolole Village
    TI Sebobi, M Kelepile, H Garekae, TT Mosekiemang
    Sanitation 8 (1), 24-24 , 2024
    2024.0
  • Results in Chemistry
    K Sewawa, T Mosekiemang, K Dintwe, N Mazrui, S Ngxangxa, O Dikinya, ...