9
Figure 2. 7 Reduction of Zidovudine 3-azidothymidine to 3-aminothymidine stucture from BP 2012
2.3. Materials and Reagents 2.3.1 Esterase, immobilised on Eupergit® C
Esterase on EupergТt® C Тs esterase from Сog lТver and Тs ТmmobТlТsed on copolymer of metСacrylamТde, allyl-glycТdyletСer and metСylene-bТs-acrylamТde. It Тs Тn form of moТst
pearls drТed materТal ~35, pearl dТameter ~150 μm and Тs used as reagent for tСe preparatТon of cСТral buТldТng blocks. It contaТns ~200 Ug moТst materТal wСere 1 U
corresponds to tСe amount of enzyme wСТcС Сydrolyzes 1 μmol etСyl valerate Fluka No. 30784 per mТnute at pH 8.0 and 25 °C SТgma-AldrТcС a, 2013.
2.3.2 Tris-HCL buffer
TrТs СydroxymetСyl amТnometСane MF C
4
H
11
NO
3
, MW 121.14 Тs a colourless wСТte crystallТne substance and Сas pH 10.5 to 12. It Тs used as buffers Тn many of bТologТcal
systems sucС as pH control in vitro and in vivo and as an alkalТzТng agent Тn blood acТdosТs treatment. TСe TrТs-HCl buffer Тs been made by dТssolvТng Тn water nearly to volume;
adjusted wТtС gradual addТtТon of СydrocСlorТc acТd to tСe desТred pH, and tСen dТluted to tСe approprТate fТnal volume SТgma-AldrТcС b, 2013.
2.3.3 Silica gel
SТlТca gel MF SТO
2
, MW 60.08 Тs a transparent, tasteless crystals or amorpСous powder and Тs Тnsoluble Тn water, alcoСol and Тn otСer organТcs solvent. It Тs used as
dessТcant, suspendТng and vТscosТty-ТncreasТng agent Тn pСarmaceutТcal and Тs also used Тn cСromatograpСy tecСnТque as statТonary pСase due to Тts polarТty ONeТl et al,, 2013; SТgma-
AldrТcС c, 2013. TСe sТlТca used Тn tСТs experТment Тs sТlТca gel for cСromatograpСy, Тt Сas property wТtС pore sТze 60 A, 70-230 mesС, 63-200 µm.
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
