Ngumba, E., Gachanja, A., Tuhkanen, T., 2016a. Occurrence of selected antibiotics and antiretroviral drugs in Nairobi River Basin, Kenya. Sci. Total Environ. 539, 206–213. doi:10.1016/j.scitotenv.2015.08.139

Ngumba, E., Kosunen, P., Gachanja, A., Tuhkanen, T., 2016b. A multiresidue analytical method for trace level determination of antibiotics and antiretroviral drugs in wastewater and surface water using SPE-LC-MS/MS and matrix-matched standards. Anal. Methods 8, 6720–6729. doi:10.1039/C6AY01695B

Ng’ang’a F, Gachanja A., Onditi A. and Ngumba E., Application of Solid Phase Extraction with Gas Chromatography -Mass Spectrometry in Geographical Profiling and Characterization of Volatile Organics in Kenyan Honey. Journal of Food Science and Quality Management Vol 5 2012

Harrison Wanyika, Erastus Gatebe, Paul Kioni, Zhiyong Tang and Yan Gao. Mesoporous Silica Nanoparticles Carrier for Urea: Potential Applications in Agrochemical delivery systems. J. Nanosci. Nanotechnol. 12, 2221 – 2228 (2012)

Karanja B.K., Inoti, I.K., Thiong’o G.T., and Keriko J.M., (2012) A Method of converting low density polyethylene into useful product, International Journal of applied environmental sciences (193-203)

Keno D Kowanga, E Gatebe, G T Thiong’o and P Kareru (2012). Biosorption of Cu(II) and Pb(II) using Maerua subcordata root tubers. Tanzania Journal of Natural and Applied Sciences (TaJONAS), ISSN 1821-7249, pp 409-415


 H. N. Wanyika, P G Kareru, L M Gitu, E. G. Gatebe and B. N. Muyemba. Quantification of Albendazole in Dewormer Formulations  in the Kenyan market. Adv. Appl. Sci. Res. 2(2): 9 – 13 (2011).

Harrison Wanyika, Erastus Gatebe, Paul Kioni, Zhiyong Tang and Yan Gao. Synthesis and characterization of ordered Mesoporous Silica Nanoparticles with tunable physical properties by varying molar composition of the reagents. Afr. J. Pharm. Pharmacol. 5(21): 2402-2410 (2011).

John K Muthee, Daniel W Gakuya, James M Mbaria, Patrick G Kareru, Charles M. Mulei J, Francis K Njonge (2011). Ethnobotanical study of anthelmintic and other medicinal plants traditionally used in Loitoktok district of Kenya, Journal of Ethnopharmacology, 135: 15-21

Karanja B.K., Inoti, I.K., Thiong’o G.T., and Keriko J.M., (2011) a method of converting low densiry polystyurene into a waterproof paint. Journal of environmental issues 48-55

Mbiri A, Onditi A, Oyaro N. and Murago E. (2011) determination of essential and heavy metals in Kenyan Honey by Atomic absorption and emission Spectroscopy, Journal of Agriculture and Technology, Vol 13 No. 1 pp107-113

Mercy Githua, Patrick Kareru, Ahmed Hassanali, Joseph Keriko, Grace Murilla, Mary Ndungu and Gathu Nyagah (2011). Antitrypanosomal Tetratriterpenoids from Toona ciliata roots. Agriculture and Biology Journal of North America, 2(7): 1042-1047

Muiruri P. M., Nyagah C. G., Njenga J. W. and Gitu L. M. (2011).  Comparison of Distribution of Phosphorus in Minjingu Phosphate Rock to Mrima Hill and Magadi Rock Samples. Journal of the Kenya Chemical Society, Vol 6 (1) pp 42- 52

Ogwayo I. O., and Onditi A.O. (2011) The effect of potatoes in the maize and beans composite meal on the bioavailability of iron and zinc by In-Vitro method. International Journal of current research Volume 3 issue 5

Onditi O. Anam and Kinuthia Magdaline (2011) Improvement of sensitivity in AAS by solving interferences, international journal of Physical science Vol 3 issue 5

P.G. Muigai, P.M. Shiundu, F.B. Mwaura and G.N. Kamau (2011). ‘Initial Correlations among the Levels of Various Nutrient Species in Water from Nairobi Dam, Kenya’. Int. J. Biochemiphys; Vol. 19, P. 25 – 36.

Patrick L Kinney, Michael Gatari Gichuru, Nicole Volavka-Close, Nicole Ngo, Peter K Ndiba, Anna Law, Anthony Gachanja, Samuel Mwaniki Gaita, Steven N Chillrud, Elliott Sclar Traffic Impacts on PM(2.5) Air Quality in Nairobi, Kenya. Environmental Science Policy Vol14, 2011, 369-378


 P.G. Muigai, P.M. Shiundu, F.B. Mwaura and G.N. Kamau (2010). ‘Correlation between Dissolved Oxygen and Total Dissolved Solids and Their Role in the Eutrophication of Nairobi Dam, Kenya’. Int. J. Biochemiphys; Vol. 18(1) 1 – 15.

P.G. Muigai, P.M. Shiundu, F.B. Mwaura and G.N. Kamau (2010). ‘Phosphorous as the Limiting Nutrient Element for the Eutrophication of Nairobi Dam, Kenya’. Int. J. Biochemiphys; 18(1) 16 – 31.

Cyrus G Wagate, James M Mbaria, Daniel W Gakuya, Mark O Nanyingi, Kareru P G, Kimani Njung’e, Nduhiu Gitahi, James K Macharia. (2010). Screening of Kenyan medicinal Plants for antibacterial activity. Phytotherapy Research: 24: 150-153

H. N. Wanyika, A. N.   Gachanja, G. M. Kenji, J. M. Keriko   and A. N. Mwangi. A rapid method based on UV spectrophotometry for Quantitative determination of allicin in aqueous garlic extracts. JAGST 12 (1): 74 – 82 (2010).

H. N. Wanyika,   E. G. Gatebe, L. M. Gitu, E. K. Ngumba and C. W. Maritim. Determination of caffeine content of tea and instant coffee brands found in the Kenyan market. Afr.  J.  Food   Sci. 4(6): 353 – 358 (2010).

Kareru P.G*, Keriko, J.M, Kenji, G.M, Thiong’o, G.T, Gachanja, A.N, Mukiira, H.N (2010). Antimicrobial activities of skincare preparations from plant extracts. African Journal of Complementary and Alternative Medicine, 7(3): 214-218

Kareru P.G*, J.M. Keriko, G.M. Kenji and A.N. Gachanja (2010). Anti-termite and antimicrobial properties of paint made from Thevetia peruviana (Pers.) Schum. oil extract. African Journal of Pharmacy and Pharmacology, 4(2): 87-89

Keriko, J M., Chege, C W, Magu, M M., Mwachiro, E C., Murigi, A N., Githua, M N. and Kareru, P G. (2010). Fish lipid contents and classes of selected fish species found in Lake Naivasha (Kenya) and the fish feeding habits of the lake’s inhabitants. African Journal of Pharmacy and Pharmacology, 4(10): 745-753


 H.N. Wanyika, P.G. Kareru,  J.M. Keriko, A.N. Gachanja, G.M. Kenji   and N.J Mukiira. Contact toxicity of some fixed plant oils and stabilized natural pyrethrum extracts against adult maize weevils (Sitophilus zeamais Motschulsky). Afr.  J.  Pharm. Pharmacol. 3(2): 066-069 (2009).

Jackson K. Kiptoo, J. Catherine Ngila and Ned D. Silavwe. Evaluation of copper speciation in model solutions of humic acid by mini-columns packed with Chelex-100 and new chelating agents: Application to speciation of selected heavy metals in environmental water samples. Journal of Hazardous Materials, 2009, 172,1163-1167.

Kareru P G*., Wanyika H N., Kenji G M., Keriko J M., Gachanja A N., and Mukiira N J (2009) Contact toxicity of some fixed plant oils and stabilized natural pyrethrum extracts against adult maize weevils (Sitophilus zeamais Motschulsky). African Journal of Pharmacy and Pharmacology, 3(2): 066-069

Mburu DM, Ochola L., Maniania NK, Njagi PG, Gitonga LM, Ndungu MW, Wanjoya AK, Hassanali A. Relationship between virulence and repellency of entomopathogenic isolates of Metarhizium anisopliae and Beauveria bassiana to the termite Macrotermes michaelseni. Journal of Insect Physiology, 55, 774-780, 2009