EDWIN SHIGWENYA MADIVOLI

Dr. EDWIN SHIGWENYA MADIVOLI

Chemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Nairobi City, Kenya
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Research Focus & Metrics

Academic Career Length

13Years (2014-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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28 August 2023 in Scientific Reports
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DNDennis Mwanza Nzilu
Dennis Mwanza Nzilu
EMEDWIN SHIGWENYA MADIVOLI
EDWIN SHIGWENYA MADIVOLI
DMDavid Sujee Makhanu
David Sujee Makhanu
SWSammy Indire Wanakai
Sammy Indire Wanakai
GKGideon Kirui Kiprono
Gideon Kirui Kiprono
PKPatrick Gachoki Kareru
Patrick Gachoki Kareru
In recent ages, green nanotechnology has gained attraction in the synthesis of metallic nanoparticles due to their cost-effectiveness, simple preparation steps, and environmentally-friendly. In the present study, copper oxide nanoparticles (CuO NPs) were prepared usingParthenium hysterophoruswhole plant aqueous extract as a reducing, stabilizing, and capping agent. The CuO NPs were characterized via UV–Vis Spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), powder X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and Dynamic Light Scattering (DLS). The UV–Vis spectra of CuO NPs showed a surface plasmonic resonance band to occur at 340 nm. FTIR analysis revealed the presence of secondary metabolites on the surface of CuO NPs, with a characteristic Cu–O stretching band being identified at 522 cm−1. Scanning electron micrographs and transmission electron micrographs showed that CuO NPs were nearly spherical, with an average particle of 59.99 nm obtained from the SEM micrograph. The monoclinic crystalline structure of CuO NPs was confirmed using XRD, and crystallite size calculated using the Scherrer-Debye equation was found to be 31.58 nm. DLS showed the presence of nanoparticle agglomeration, which revealed uniformity of the CuO NPs. Furthermore, the degradation ability of biosynthesized nanoparticles was investigated against rifampicin antibiotic. The results showed that the optimum degradation efficiency of rifampicin at 98.43% was obtained at 65℃ temperature, 50 mg dosage of CuO NPs, 10 mg/L concentration of rifampicin solution, and rifampicin solution at pH 2 in 8 min. From this study, it can be concluded that CuO NPs synthesized fromParthenium hysterophorusaqueous extract are promising in the remediation of environmental pollution from antibiotics. In this light, the study reports thatParthenium hysterophorus-mediated green synthesis of CuO NPs can effectively address environmental pollution in cost-effective, eco-friendly, and sustainable ways.

29 April 2019 in SN Applied Sciences
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EMEDWIN SHIGWENYA MADIVOLI
EDWIN SHIGWENYA MADIVOLI
PKPatrick Gachoki Kareru
Patrick Gachoki Kareru
EMErnest Gachui Maina
Ernest Gachui Maina
ANAugustine Otieno Nyabola
Augustine Otieno Nyabola
SWSammy Indire Wanakai
Sammy Indire Wanakai
JNJared Onyango Nyang’aU
Jared Onyango Nyang’aU

19 July 2019 in Journal of Inorganic and Organometallic Polymers and Materials
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YGYahaya Gavamukulya
Yahaya Gavamukulya
EMEsther N. Maina
Esther N. Maina
AMAmos M. Meroka
Amos M. Meroka
EMEDWIN SHIGWENYA MADIVOLI
EDWIN SHIGWENYA MADIVOLI
HEHany A. El-Shemy
Hany A. El-Shemy
GMGabriel Magoma
Gabriel Magoma

14 June 2019 in SN Applied Sciences
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EMEDWIN SHIGWENYA MADIVOLI
EDWIN SHIGWENYA MADIVOLI
PKPatrick Gachoki Kareru
Patrick Gachoki Kareru
AGAnthony Ngure Gachanja
Anthony Ngure Gachanja
SMSamuel Mutuura Mugo
Samuel Mutuura Mugo
DMDavid Sujee Makhanu
David Sujee Makhanu

10 January 2016 in International Research Journal of Pure and Applied Chemistry
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EMEDWIN SHIGWENYA MADIVOLI
EDWIN SHIGWENYA MADIVOLI
PKP. G. Kareru
P. G. Kareru
AGA. N. Gachanja
A. N. Gachanja
Samuel MugoSamuel Mugo
Samuel Mugo
MMM. K. Murigi
M. K. Murigi
FNF.K. Njonge
F.K. Njonge
Cellulose is an inexpensive, renewable, bio-based and an abundant raw material suitable for the development of filter membranes for water purification. This is because it has numerous functional groups that afford ease of modification to create active surfaces upon chemical modification. In this study, cellulose was isolated from two abundant biomasses, namely, Eichhornia crassipes and Cyperus papyrus using the soda process followed by bleaching with peracetic acid. The percent yield of cellulose nanofibrils (CNF) obtained from E. crassipes and C. papyrus was found to be 31.64 ± 1.46% and 29.55 ± 0.64% respectively. The degree of crystallinity and crystal sizes were calculated to be 71.42% and 0.059 nm for E. crassipes and 46.15% and 0.068 nm for C. papyrus respectively. The FT-IR absorption of the carbonyl functional group of an ester indicated that effective esterification of cellulose using citric acid was obtained when cellulose nanofibrils to citric acid ratio was 1:1. From batch adsorption studies, the capacity for citric acid modified cellulose to remove heavy metals was determined to be 8.36 mg/g Zn2+, 18.06 mg/g Cu2+, 42.69 mg/g Cd2+ and 21.64 mg/g Pb2+. In comparison to the % adsorption using unmodified cellulose of less than 5%, the heavy metals adsorption using modified nanocellulose materials were 86.47% Pb2+, 85.20% Cd2+, 77.40% Cu2+, and 70.04% Zn2+. From these results, it was concluded that modified cellulose could be used as a low cost adsorbent for removal of heavy metals and that development of household water filtration units using modified cellulose could be exploited.

2 April 2024 in BMC Complementary Medicine and Therapies
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WMWangui Clement Mwangi
Wangui Clement Mwangi
WWWalyambillah Waudo
Walyambillah Waudo
EMEDWIN SHIGWENYA MADIVOLI
EDWIN SHIGWENYA MADIVOLI
JGJoyline Gichuki
Joyline Gichuki
Background: A study carried out by World Health Organization revealed that around 80% of individuals globally depends on herbal forms of medication with 40% of pharmaceutical products being sourced from medicinal plants. The study objective was to evaluate the phytochemicals composition, in vitro antimicrobial and antioxidant properties of the leaves of Terminalia catappa L. aqueous and methanolic extracts. Methods: Antimicrobial activity was analyzed by disk diffusion, the minimum inhibitory concentration in-vitro assays with ciprofloxacin as the standard for antibacterial assay while nystatin for antifungal assay. Ferric reducing antioxidant power and 2,2-diphenyl-1-picryl-hydrazyl-hydrate assays were used for the evaluation of antioxidant properties of the crude extracts while the groups responsible for this activity identified using Fourier transform infrared spectrophotometer. Results: The study found that the leaves of Terminalia catappa contained alkaloids, tannins, steroids, cardiac glycosides, flavonoids, phenols, saponins, and coumarins, but terpenoids were absent. Presence of functional groups associated with this class of compounds such as OH vibrational frequencies were observed in IR spectrum of the crude extracts. Methanolic extract from Terminalia catappa exhibited greater antibacterial properties against Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus, whereas aqueous extract displayed greater antibacterial activity against Bacillus subtilis for all concentrations tested. The amount of the sample that scavenged 50 percent of DPPH (IC50) was found to be 8.723, 13.42 and 13.04 µg/mL for L-ascorbic acid, Terminalia catappa L. methanolic and aqueous extracts respectively. The antimicrobial and antioxidant activities varied with the extract concentration and solvent used in extractions. Conclusion: Terminalia catappa L. leaves are prospective for use as a source of therapeutic agents that could lead to the advancement of new antimicrobial and antioxidant products.