instrumentation, simplicity, speed, precision,
accuracy, and low cost (Tehrani et al., 2014).
Copper determination can be conducted by
atomic absorption spectrophotometry (AAS).
Several studies had determined Cu levels in samples
such as Windri (2011), Listiowati et al., (2011) and
Sa'adah and Winata (2010) that examinied Cu levels
in samples using AAS.
Another method in addition to AAS is UV-Vis
Spectrophotometry which use a variety of
complexing agents. Applicable complexing agents
are 6- (2-Methoxynaphthyl) -2,3-dihydro-1,2,4-
triazine-3-thione that was carried out by Tehrani et
al. (2014), Ligan (2- [6-Nitro -2-benzothiazolylazo]
-4-hydroxy benzoic acid) that was carried out by
Jreo (2015) and neocuproine that was carried out by
Itnawita and Bali (2012).
Copper (Cu) examination using UV-Vis
Spectrophotometry with neocuproine complexing
agent (American Public Health Association) and
Atomic Absorption Spectrophotometry (SNI 06-
6989.6-2004) are well established and standardized
methods. Validation is usually performed for newly
manufactured and developed analytical methods,
whereas for available and standardized methods (e.g.
from AOAC, ASTM, and others) in exception for
the first time use in certain laboratories, validation is
usually unnecessary, only verification is required.
Verification of analysis method is a method
validation measure, an assessment of certain
parameters aimed to prove that the parameters meet
the requirements for its application. Parameter
verification methods include: linearity, detection and
quantitative limit, accuracy, and precision
(Anggraini, 2016). Based on description above, the
authors aim to find the difference of copper (Cu)
examination results using UV-Vis
Spectrophotometry with neocuproine complexing
agents and Atomic Absorption Spectrophotometry
(AAS) in which method verification will be
performed.
2. SUBJECT AND METHODS
This study was conducted in Balai Riset and
Standarisasi Industri (BARISTAND) from April 09
to May 03, 2017. The samples in this study were
made using SRM based on the standard working
range that were made from pure Copper (Cu)
products from NIST (National Institute of Standards
and Technology). The standard working range of
UV-Vis Spectrophotometry were 0.0; 0.4; 1,2; 2.0;
2.8; and 3.6 ppm (Standard Method, 2005) while
Atomic Absorption Spectrophotometry were 0.0
ppm; 0.2 ppm; 0.5 ppm; 1 ppm; 2 ppm; 3 ppm and 4
ppm (SNI 06-6989.6-2004). Water samples were
taken at three points 0.5 ppm; 1.0 ppm; and 2.0 ppm.
This study is a comparative study. The
examination methods used in this study is UV-Vis
Spectrophotometry with neocuproine complexing
agent and Atomic Absorption Spectrophotometry
(AAS).
3. RESULTS AND DISCUSSION
3.1 Verification of UV-Vis
Spectrophotometry and AAS
Methods
Method verification is a reconfirmation measure by
testing a method by completing objective evidences,
whether the methods meet the established
requirements and fit the objectives.
3.1.1 Determination of Wavelength on UV-
Vis Spectrophotometry
Determination of wavelength was conducted by
measuring the absorbance of copper standard
solution of 2 ppm concentration in the wavelength
range of 400 – 550 nm. The results of maximum
wavelength measurements were presented in Figure
1.
Figure 1: UV-Vis Spectrophotometry Wavelength Curve
Based on above figure of wavelength spectrum, a
wavelength of 456 nm was obtained. Wavelength
range for copper examination using UV-Vis
spectrophotometry with a neocuproine complexing
agent is 450 – 460 nm (American Public Health
Association).