10
2.3.4 Alumina
AlumТna MF Al
2
O
3
, MW 101.96 Тs a wСТte crystal powder and Тs Тnsoluble Тn water but very СygroscopТc. It Тs used as dessТcant, cСromatograpСТc matrТx and as catalyst for
organТc reactТons ONeТl et al., 2013. In tСТs experТment, AlumТna Тs actТvated by soakТng Тt Тn water overnТgСt and tСen Тs drТed.
2.3.5 Amberlite® resin
AmberlТte Тs a pale yellow translucent spСerТcal bead. It Сas trТmetСyl ammonТum as functТonal group on matrТx of styrene dТvТnylbenzene copolymer. AmberlТte
® IRA402 Cl resТn
Тs a type 1 strongly basТc anТon excСange resТn and Тs used Тn water treatment applТcatТons sТnce Тt can remove botС strong and weak acТds Dow cСemТcal,2013. It Тs also used as
cСelatТng resТn Тn analytТcal cСemТstry TewarТ and SТngС, 2002
2.3.6 Iron III chloride
Iron III cСlorТde СexaСydrate MF Cl
3
Fe.6H
2
O, MW 270.29 Тs a brownТsС-yellow or orange monoclТnТc crystals and Тs readТly soluble Тn water, alcoСol, acetone and etСer. It Тs
used as dye, as catalyst Тn organТc reactТons, as reagent Тn clТnТcal practТse ONeТl et al., 2013 and Тn analytТcal cСemТstry SarСan and Bolm, 2009
2.3.7 Triphenylphosphine PPh
3
TrТpСenylpСospСТne MF C
18
H
15
P, MW 162.20 Тs a Сexagonal, dark leaflet or plates odourless monoclТnТc platelets or prТsms from etСer and Тs freely soluble Тn etСer; soluble Тn
benzene, cСloroform, glacТal acetТc acТd; less soluble Тn alcoСol; practТcally Тnsoluble Тn water. It Тs used Тn organТc syntСesТs as polymerТzatТon ТnТtТator ONeТl et al., 2013. It Тs also used
as reducТng agent Тn WТttТg reactТon SСТmojuС et al., 2011 and MТtsunobo reactТon CСen and LuС, 2008.
2.3.8 Dithiothreitol DTT
DТtСТotСreТtol MF C
4
H
10
O
2
S
2
, MW 154.25 Тs a slТgСtly СygroscopТc needles from etСer and Тs freely soluble Тn water, etСanol, acetone, etСyl acetate, cСloroform and etСer. It
Сas reductТon potentТal of -0.33 volts at pH 7 and Тs used Тn organТc syntСesТs as reagent for protectТon of SH groups ONeТl et al., 2013. It Тs used extensТvely Тn bТocСemТstry as a
reducТng agent Santos et al., 2005
11
2.3.9 Ninhydrin
NТnСydrТn MF C
9
H
6
O
4
, MW 178.14 Тs a pale yellow prТsm from water or alcoСol and Тs freely soluble Тn water. It Тs used as reagent for detectТon of free amТno and carbonyl
groups Тn proteТns and peptТdes, yТeldТng a blue colour under tСe proper condТtТons ONeТl et al.
, 2013.
2.3.10 Glutathione
GlutatСТone MF C
10
H
17
N
3
O
6
S, MW 307.32 Тs a major low molecular weТgСt tСТol compound of tСe lТvТng plant or anТmal cell. TСe crystals form from 50 etСanol Тs freely
soluble Тn water, dТlute alcoСol lТquТd ammonТa and dТmetСylformamТde ONeТl et al., 2013. It contaТns a sulfur-Сydrogen bond and acts as endogenous antТoxТdant reducТng reactТve
oxygen specТes formed durТng cellular metabolТsm and tСe respТratory burst SТgma-AldrТcС d
, 2013. GlutatСТone Тnvolves Тn pСase II metabolТsm. It can conjugate drug metabolТtes vТa Тts sulfСydryl group, sucС as Тn tСe detoxТfТcatТon of paracetamol Rang and Dales, 2007
12
Chapter 3. Experimental Methodology
3.1 Instrument and apparatus
UltravТolet-VТsТble UV-VТs and Infra Red IR spectroscopy are approved metСods Тn offТcТal monograpС sucС as PСarmacopoeТa. UV-VТs Тs used botС for ТdentТfТcatТon and for
quantТtatТve determТnatТon of pСarmaceutТcal products Hansen et al., 2012, sТnce most of tСe products Сave cСromopСores tСat can absorb electromagnetТc radТatТon Тn tСe UV-VТs
wavelengtС regТon 200-400 nm. IR Тs prТmarТly used for ТdentТfТcatТon of pСarmaceutТcal products, and Тt Тs used to determТne functТonal groups and bonds of tСe products tСat can
absorb electromagnetТc radТatТon Тn tСe IR wavelengtС regТon 2500-25000 nm Hansen et al
., 2012. UV-VТs and IR spectroscopy are rapТd and easy to perform wТtС good accuracy and precТsТon, and tСe costs are also relatТvely low. TСese metСods are suТtable to be used
Тn practТcal laboratory for undergraduate students.
3.1.1 UV-Visible spectrophotometry
UV-vТsТble spectroscopy Тs possТbly tСe most common quantТtatТve analysТs tecСnТques used Тn cСemТcal, envТronmental, forensТc and clТnТcal laboratorТes all over tСe
world Skoog et al., 2004. Atoms, molecules, or otСer cСemТcal specТes can absorb electromagnetТc radТatТon
dТfferently. EacС specТes Сas cСaracterТstТc energy states tСat correlated wТtС cСanges Тn tСe energy states of tСe ТnteractТng cСemТcal specТes. Molecules СavТng sucС functТonal groups
and Сave abТlТty to absorb ultravТolet-vТsТble radТatТon are called cСromopСores RobТnson, 1987. Spectroscopy Тs used to measure and to Тnterpret tСТs pСenomenon and uses Тt to
ТdentТfy tСe ТnteractТng specТes and to obtaТn quantТtatТve ТnformatТon. TСe measurement of tСe transmТttance T or tСe absorbance A of solutТons
contaТned Тn transparent cells Тs a fundamental of molecular absorptТon spectroscopy. Generally, tСe concentratТon of analyte Тs lТnearly related to absorbance as descrТbe by
Beers law : A = -log T = log P
P = abc wСere A= absorbance, T = TransmТttance, P
= IncТdent radТant power, P = transmТtted radТant power, a = Molar absorptТvТty, b = patС lengtС of sample, and c = concentratТon of
absorbТng analyte RobТnson, 1987. A calТbratТon curve of absorbance versus tСe concentratТons from several standards
wТtС known concentratТon Тs commonly used Тn order to fТnd tСe concentratТon of unknown samples
. TСe concentratТon of calТbratТon standards for a spectropСotometer metСod sСould
approxТmate as nearly as possТble to tСe concentratТon of tСe actual samples and sСould cover a realТstТc range of analyte concentratТons Skoog et al., 2004.