The Malaysian Journal of Analytical Sciences Vol 16 No 2 (2012): 148 – 156

 

 

 

EFFECTS OF VARIOUS PARAMETERS ON IN-HOUSE COCKTAIL DEVELOPED FOR THE MEASUREMENT OF GROSS ALPHA AND BETA IN AQUEOUS ENVIRONMENTAL SAMPLES USING LIQUID SCINTILATION COUNTING TECHNIQUE

 

(Kesan Pelbagai Parameter Ke Atas Koktil yang Dibangunkan Sendiri bagi Pengukuran Gros Alfa dan Beta Di Dalam Sampel Air Persekitaran Menggunakan Teknik Pembilang Sintilasi Cecair)

 

Zaini Hamzah¹, Masitah Alias¹*, Ahmad Saat², Abdul Kadir Ishak³ and Zaharudin Ahmad³

 

¹Faculty of Applied Sciences,

Universiti Teknologi MARA, 40450 Shah Alam, Selangor

²International Education Centre (INTEC),

Universiti Teknologi MARA, 40200 Shah Alam, Selangor

³Radiochemistry and Environmental Laboratory,

Malaysian Nuclear Agency, 43000 Bangi, Selangor

 

*Corresponding author: ellyaa@yahoo.com

 

 

Abstract

Liquid scintillation counting (LSC) is a versatile technique for measuring beta emitters in organic liquid samples. When this technique is applied to the aqueous environmental samples, the limitation is to incorporate the aqueous phase which contains the radionuclides of interest into an organic phase which can readily mix with a scintillator that is responsible for the detection of photon through excitation processes. The in-house cocktail was developed by mixing the organic solvent which contains primary and secondary solutes with a specific emulsifier (Triton-N101) which is capable of linking the aqueous phase to the organic phase through its hydrophilic and hydrophobic tails. The best proportion for water: toluene: Triton-N101 is 2: 4: 4, respectively. Since the aqueous environmental samples are analyzed, there is a need to study various effects such as pH, buffer and salts on the cocktail to ensure the stability of the cocktail being used. ³H and ²³²U tracers were used throughout this study. pH value shows an optimal condition for both tracers, while  acid, base, buffer and salts all show decreased in counting efficiency when the their concentrations increased.

 

Keywords: liquid scintillation counting, cocktail, emulsifier, Triton N101, tritium

 

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