Transcript Makalah Prof. Dibyo 3

Metode
Spektrofotometri
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Spektrofotometri
Teknik analisis yang berhubungan
dengan
penggunaan cahaya
untuk
- melihat pola spektrum senyawa
- mengukur konsentrasi bahan kimia
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Conventional
Spectrophotometer
Schematic of a conventional single-beam spectrophotometer
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Penyerapan warna yang
berbeda
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Anilin vs Pelarut
NH2
1
10 mg/L dlm etanol
2
200 mg/L dlm 0,1N HCl
C6H7N
3
10 mg/L dlm (1+99) NaOH
Ibuprofen [ C13H18O2 ]
COOH
CH3
H3C
CH3
BM = 206,3
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PK. Ibuprofen Spektro UV
Pelarut
Air-basa
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1%
1cm
A
( 265 nm )
18,5
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Meloksikam
Sifat fisika-kimia ?
Adakah kromofor dan auksokrom ?
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The Magnitude of Molar absorptivity is 0 to around 105
e = 8.7 x
19
10
PA
P: transition probability (0 to 1)
A: cross sectional target area in square centimeters
(for organic molecules, this number is around 10-15
cm2).
Forbidden transition: P = 0.01; e < 103
Allowed transition: P = 0.1 to 1
Strong absorption: e = 104 to 105 L/ (mol*cm)
Weak absorption: e =103 L/ (mol*cm)
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Rumus Pendekatan
E
1%
1cm
Pada pelarut dan  tertentu
Rumus Pendekatan
A=ebc
e=
E
1% x BM
10
1cm
Propil barbital vs Fenobarbital
O
O
C
NH
C
NH
C
C
C
NH
H3C-H2C
H2C=CH-CH2
C
C
C
NH
O
O
H2C=CH-CH2
O
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O
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Spektrum Fenobarbital
Ultraviolet Spectrum
O
C
O
NH
C
H3C-H2C
H3C-H2C C
C
C
C
N
O
C
O
NH
_
O
C
N
_
O
Fenobarbital
dalam larutan bufer pH 9,2
O
C
H3C-H2C
NH
C
C
C
N
O
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Auksokrom
_
O
Kromofor16
Spektrum propil barbital
O
C
NH
C
C
C
NH
H2C=CH-CH2
O
H2C=CH-CH2
O
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Papaverin HCl
H3CO
N
H3CO
CH2
OCH3
.HCl
OCH3
Kunang-kunang
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Visible Spectrum
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Colors of Visible light
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Paprika
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Lycopene  Tomato
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Zeaxanthin  Corn
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-Carotene  Wortel
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