char = S;code = 83
char = p;code = 112
char = e;code = 101
char = c;code = 99
char = t;code = 116
char = r;code = 114
char = o;code = 111
char = p;code = 112
char = h;code = 104
char = o;code = 111
char = t;code = 116
char = o;code = 111
char = m;code = 109
char = e;code = 101
char = t;code = 116
char = r;code = 114
char = i;code = 105
char = c;code = 99
char = ;code = 32
char = d;code = 100
char = e;code = 101
char = t;code = 116
char = e;code = 101
char = r;code = 114
char = m;code = 109
char = i;code = 105
char = n;code = 110
char = a;code = 97
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = ;code = 32
char = o;code = 111
char = f;code = 102
char = ;code = 32
char = a;code = 97
char = s;code = 115
char = c;code = 99
char = o;code = 111
char = r;code = 114
char = b;code = 98
char = i;code = 105
char = c;code = 99
char = ;code = 32
char = a;code = 97
char = c;code = 99
char = i;code = 105
char = d;code = 100
char = ;code = 32
char = a;code = 97
char = n;code = 110
char = d;code = 100
char = ;code = 32
char = d;code = 100
char = e;code = 101
char = h;code = 104
char = y;code = 121
char = d;code = 100
char = r;code = 114
char = o;code = 111
char = a;code = 97
char = s;code = 115
char = c;code = 99
char = o;code = 111
char = r;code = 114
char = b;code = 98
char = i;code = 105
char = c;code = 99
char = ;code = 32
char = a;code = 97
char = c;code = 99
char = i;code = 105
char = d;code = 100
char = .;code = 46
result sql = Spectrophotometric determination of ascorbic acid and dehydroascorbic acid.
Spectrophotometric determination of ascorbic acid and dehydroascorbic acid.
char = W;code = 87
char = e;code = 101
char = ;code = 32
char = p;code = 112
char = r;code = 114
char = e;code = 101
char = s;code = 115
char = e;code = 101
char = n;code = 110
char = t;code = 116
char = ;code = 32
char = a;code = 97
char = ;code = 32
char = m;code = 109
char = e;code = 101
char = t;code = 116
char = h;code = 104
char = o;code = 111
char = d;code = 100
char = ;code = 32
char = f;code = 102
char = o;code = 111
char = r;code = 114
char = ;code = 32
char = m;code = 109
char = e;code = 101
char = a;code = 97
char = s;code = 115
char = u;code = 117
char = r;code = 114
char = i;code = 105
char = n;code = 110
char = g;code = 103
char = ;code = 32
char = a;code = 97
char = s;code = 115
char = c;code = 99
char = o;code = 111
char = r;code = 114
char = b;code = 98
char = i;code = 105
char = c;code = 99
char = ;code = 32
char = a;code = 97
char = c;code = 99
char = i;code = 105
char = d;code = 100
char = ;code = 32
char = i;code = 105
char = n;code = 110
char = ;code = 32
char = m;code = 109
char = e;code = 101
char = t;code = 116
char = h;code = 104
char = a;code = 97
char = n;code = 110
char = o;code = 111
char = l;code = 108
char = /;code = 47
char = t;code = 116
char = r;code = 114
char = i;code = 105
char = c;code = 99
char = h;code = 104
char = l;code = 108
char = o;code = 111
char = r;code = 114
char = o;code = 111
char = a;code = 97
char = c;code = 99
char = e;code = 101
char = t;code = 116
char = i;code = 105
char = c;code = 99
char = ;code = 32
char = a;code = 97
char = c;code = 99
char = i;code = 105
char = d;code = 100
char = ;code = 32
char = e;code = 101
char = x;code = 120
char = t;code = 116
char = r;code = 114
char = a;code = 97
char = c;code = 99
char = t;code = 116
char = s;code = 115
char = ;code = 32
char = p;code = 112
char = r;code = 114
char = e;code = 101
char = p;code = 112
char = a;code = 97
char = r;code = 114
char = e;code = 101
char = d;code = 100
char = ;code = 32
char = f;code = 102
char = r;code = 114
char = o;code = 111
char = m;code = 109
char = ;code = 32
char = h;code = 104
char = u;code = 117
char = m;code = 109
char = a;code = 97
char = n;code = 110
char = ;code = 32
char = p;code = 112
char = l;code = 108
char = a;code = 97
char = s;code = 115
char = m;code = 109
char = a;code = 97
char = ;code = 32
char = a;code = 97
char = f;code = 102
char = t;code = 116
char = e;code = 101
char = r;code = 114
char = ;code = 32
char = e;code = 101
char = n;code = 110
char = z;code = 122
char = y;code = 121
char = m;code = 109
char = a;code = 97
char = t;code = 116
char = i;code = 105
char = c;code = 99
char = ;code = 32
char = o;code = 111
char = x;code = 120
char = i;code = 105
char = d;code = 100
char = a;code = 97
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = ;code = 32
char = o;code = 111
char = f;code = 102
char = ;code = 32
char = a;code = 97
char = s;code = 115
char = c;code = 99
char = o;code = 111
char = r;code = 114
char = b;code = 98
char = i;code = 105
char = c;code = 99
char = ;code = 32
char = a;code = 97
char = c;code = 99
char = i;code = 105
char = d;code = 100
char = ;code = 32
char = t;code = 116
char = o;code = 111
char = ;code = 32
char = d;code = 100
char = e;code = 101
char = h;code = 104
char = y;code = 121
char = d;code = 100
char = r;code = 114
char = o;code = 111
char = a;code = 97
char = s;code = 115
char = c;code = 99
char = o;code = 111
char = r;code = 114
char = b;code = 98
char = i;code = 105
char = c;code = 99
char = ;code = 32
char = a;code = 97
char = c;code = 99
char = i;code = 105
char = d;code = 100
char = ;code = 32
char = b;code = 98
char = y;code = 121
char = ;code = 32
char = a;code = 97
char = s;code = 115
char = c;code = 99
char = o;code = 111
char = r;code = 114
char = b;code = 98
char = a;code = 97
char = t;code = 116
char = e;code = 101
char = ;code = 32
char = o;code = 111
char = x;code = 120
char = i;code = 105
char = d;code = 100
char = a;code = 97
char = s;code = 115
char = e;code = 101
char = .;code = 46
char = ;code = 32
char = S;code = 83
char = a;code = 97
char = m;code = 109
char = p;code = 112
char = l;code = 108
char = e;code = 101
char = s;code = 115
char = ;code = 32
char = w;code = 119
char = e;code = 101
char = r;code = 114
char = e;code = 101
char = ;code = 32
char = a;code = 97
char = s;code = 115
char = s;code = 115
char = a;code = 97
char = y;code = 121
char = e;code = 101
char = d;code = 100
char = ;code = 32
char = b;code = 98
char = y;code = 121
char = ;code = 32
char = s;code = 115
char = p;code = 112
char = e;code = 101
char = c;code = 99
char = t;code = 116
char = r;code = 114
char = o;code = 111
char = p;code = 112
char = h;code = 104
char = o;code = 111
char = t;code = 116
char = o;code = 111
char = m;code = 109
char = e;code = 101
char = t;code = 116
char = r;code = 114
char = i;code = 105
char = c;code = 99
char = a;code = 97
char = l;code = 108
char = l;code = 108
char = y;code = 121
char = ;code = 32
char = m;code = 109
char = o;code = 111
char = n;code = 110
char = i;code = 105
char = t;code = 116
char = o;code = 111
char = r;code = 114
char = i;code = 105
char = n;code = 110
char = g;code = 103
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = k;code = 107
char = i;code = 105
char = n;code = 110
char = e;code = 101
char = t;code = 116
char = i;code = 105
char = c;code = 99
char = s;code = 115
char = ;code = 32
char = o;code = 111
char = f;code = 102
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = c;code = 99
char = o;code = 111
char = n;code = 110
char = c;code = 99
char = e;code = 101
char = n;code = 110
char = t;code = 116
char = r;code = 114
char = a;code = 97
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = -;code = 45
char = d;code = 100
char = e;code = 101
char = p;code = 112
char = e;code = 101
char = n;code = 110
char = d;code = 100
char = e;code = 101
char = n;code = 110
char = t;code = 116
char = ;code = 32
char = a;code = 97
char = b;code = 98
char = s;code = 115
char = o;code = 111
char = r;code = 114
char = b;code = 98
char = a;code = 97
char = n;code = 110
char = c;code = 99
char = e;code = 101
char = ;code = 32
char = c;code = 99
char = h;code = 104
char = a;code = 97
char = n;code = 110
char = g;code = 103
char = e;code = 101
char = s;code = 115
char = ;code = 32
char = o;code = 111
char = f;code = 102
char = ;code = 32
char = d;code = 100
char = e;code = 101
char = h;code = 104
char = y;code = 121
char = d;code = 100
char = r;code = 114
char = o;code = 111
char = a;code = 97
char = s;code = 115
char = c;code = 99
char = o;code = 111
char = r;code = 114
char = b;code = 98
char = i;code = 105
char = c;code = 99
char = ;code = 32
char = a;code = 97
char = c;code = 99
char = i;code = 105
char = d;code = 100
char = ;code = 32
char = w;code = 119
char = i;code = 105
char = t;code = 116
char = h;code = 104
char = ;code = 32
char = p;code = 112
char = h;code = 104
char = o;code = 111
char = s;code = 115
char = p;code = 112
char = h;code = 104
char = a;code = 97
char = t;code = 116
char = e;code = 101
char = -;code = 45
char = c;code = 99
char = i;code = 105
char = t;code = 116
char = r;code = 114
char = a;code = 97
char = t;code = 116
char = e;code = 101
char = -;code = 45
char = m;code = 109
char = e;code = 101
char = t;code = 116
char = h;code = 104
char = a;code = 97
char = n;code = 110
char = o;code = 111
char = l;code = 108
char = ;code = 32
char = b;code = 98
char = u;code = 117
char = f;code = 102
char = f;code = 102
char = e;code = 101
char = r;code = 114
char = s;code = 115
char = .;code = 46
char = ;code = 32
char = A;code = 65
char = s;code = 115
char = c;code = 99
char = o;code = 111
char = r;code = 114
char = b;code = 98
char = i;code = 105
char = c;code = 99
char = ;code = 32
char = a;code = 97
char = c;code = 99
char = i;code = 105
char = d;code = 100
char = ;code = 32
char = w;code = 119
char = a;code = 97
char = s;code = 115
char = ;code = 32
char = d;code = 100
char = e;code = 101
char = t;code = 116
char = e;code = 101
char = r;code = 114
char = m;code = 109
char = i;code = 105
char = n;code = 110
char = e;code = 101
char = d;code = 100
char = ;code = 32
char = a;code = 97
char = s;code = 115
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = d;code = 100
char = i;code = 105
char = f;code = 102
char = f;code = 102
char = e;code = 101
char = r;code = 114
char = e;code = 101
char = n;code = 110
char = c;code = 99
char = e;code = 101
char = ;code = 32
char = b;code = 98
char = e;code = 101
char = t;code = 116
char = w;code = 119
char = e;code = 101
char = e;code = 101
char = n;code = 110
char = ;code = 32
char = d;code = 100
char = e;code = 101
char = h;code = 104
char = y;code = 121
char = d;code = 100
char = r;code = 114
char = o;code = 111
char = a;code = 97
char = s;code = 115
char = c;code = 99
char = o;code = 111
char = r;code = 114
char = b;code = 98
char = i;code = 105
char = c;code = 99
char = ;code = 32
char = a;code = 97
char = c;code = 99
char = i;code = 105
char = d;code = 100
char = ;code = 32
char = a;code = 97
char = n;code = 110
char = d;code = 100
char = ;code = 32
char = t;code = 116
char = o;code = 111
char = t;code = 116
char = a;code = 97
char = l;code = 108
char = ;code = 32
char = a;code = 97
char = s;code = 115
char = c;code = 99
char = o;code = 111
char = r;code = 114
char = b;code = 98
char = i;code = 105
char = c;code = 99
char = ;code = 32
char = a;code = 97
char = c;code = 99
char = i;code = 105
char = d;code = 100
char = ;code = 32
char = c;code = 99
char = o;code = 111
char = n;code = 110
char = t;code = 116
char = e;code = 101
char = n;code = 110
char = t;code = 116
char = .;code = 46
char = ;code = 32
char = T;code = 84
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = d;code = 100
char = e;code = 101
char = t;code = 116
char = e;code = 101
char = c;code = 99
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = ;code = 32
char = l;code = 108
char = i;code = 105
char = m;code = 109
char = i;code = 105
char = t;code = 116
char = ;code = 32
char = w;code = 119
char = a;code = 97
char = s;code = 115
char = ;code = 32
char = <;code = 60
char = ;code = 32
char = 0;code = 48
char = .;code = 46
char = 5;code = 53
char = ;code = 32
char = m;code = 109
char = u;code = 117
char = m;code = 109
char = o;code = 111
char = l;code = 108
char = /;code = 47
char = L;code = 76
char = .;code = 46
char = ;code = 32
char = T;code = 84
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = c;code = 99
char = a;code = 97
char = l;code = 108
char = i;code = 105
char = b;code = 98
char = r;code = 114
char = a;code = 97
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = ;code = 32
char = c;code = 99
char = u;code = 117
char = r;code = 114
char = v;code = 118
char = e;code = 101
char = ;code = 32
char = w;code = 119
char = a;code = 97
char = s;code = 115
char = ;code = 32
char = l;code = 108
char = i;code = 105
char = n;code = 110
char = e;code = 101
char = a;code = 97
char = r;code = 114
char = ;code = 32
char = (;code = 40
char = r;code = 114
char = ;code = 32
char = >;code = 62
char = ;code = 32
char = 0;code = 48
char = .;code = 46
char = 9;code = 57
char = 9;code = 57
char = 5;code = 53
char = );code = 41
char = ;code = 32
char = o;code = 111
char = v;code = 118
char = e;code = 101
char = r;code = 114
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = r;code = 114
char = a;code = 97
char = n;code = 110
char = g;code = 103
char = e;code = 101
char = ;code = 32
char = 0;code = 48
char = -;code = 45
char = 1;code = 49
char = 0;code = 48
char = 0;code = 48
char = 0;code = 48
char = ;code = 32
char = m;code = 109
char = u;code = 117
char = m;code = 109
char = o;code = 111
char = l;code = 108
char = /;code = 47
char = L;code = 76
char = .;code = 46
char = ;code = 32
char = A;code = 65
char = n;code = 110
char = a;code = 97
char = l;code = 108
char = y;code = 121
char = t;code = 116
char = i;code = 105
char = c;code = 99
char = a;code = 97
char = l;code = 108
char = ;code = 32
char = r;code = 114
char = e;code = 101
char = c;code = 99
char = o;code = 111
char = v;code = 118
char = e;code = 101
char = r;code = 114
char = y;code = 121
char = ;code = 32
char = o;code = 111
char = f;code = 102
char = ;code = 32
char = a;code = 97
char = s;code = 115
char = c;code = 99
char = o;code = 111
char = r;code = 114
char = b;code = 98
char = i;code = 105
char = c;code = 99
char = ;code = 32
char = a;code = 97
char = c;code = 99
char = i;code = 105
char = d;code = 100
char = ;code = 32
char = a;code = 97
char = d;code = 100
char = d;code = 100
char = e;code = 101
char = d;code = 100
char = ;code = 32
char = t;code = 116
char = o;code = 111
char = ;code = 32
char = p;code = 112
char = l;code = 108
char = a;code = 97
char = s;code = 115
char = m;code = 109
char = a;code = 97
char = ;code = 32
char = w;code = 119
char = a;code = 97
char = s;code = 115
char = ;code = 32
char = 9;code = 57
char = 3;code = 51
char = -;code = 45
char = 1;code = 49
char = 0;code = 48
char = 5;code = 53
char = %;code = 37
char = .;code = 46
char = ;code = 32
char = T;code = 84
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = b;code = 98
char = e;code = 101
char = t;code = 116
char = w;code = 119
char = e;code = 101
char = e;code = 101
char = n;code = 110
char = -;code = 45
char = d;code = 100
char = a;code = 97
char = y;code = 121
char = ;code = 32
char = v;code = 118
char = a;code = 97
char = r;code = 114
char = i;code = 105
char = a;code = 97
char = n;code = 110
char = c;code = 99
char = e;code = 101
char = ;code = 32
char = w;code = 119
char = a;code = 97
char = s;code = 115
char = ;code = 32
char = <;code = 60
char = ;code = 32
char = 7;code = 55
char = %;code = 37
char = .;code = 46
char = ;code = 32
char = C;code = 67
char = o;code = 111
char = m;code = 109
char = p;code = 112
char = a;code = 97
char = r;code = 114
char = i;code = 105
char = s;code = 115
char = o;code = 111
char = n;code = 110
char = ;code = 32
char = o;code = 111
char = f;code = 102
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = s;code = 115
char = p;code = 112
char = e;code = 101
char = c;code = 99
char = t;code = 116
char = r;code = 114
char = o;code = 111
char = p;code = 112
char = h;code = 104
char = o;code = 111
char = t;code = 116
char = o;code = 111
char = m;code = 109
char = e;code = 101
char = t;code = 116
char = r;code = 114
char = i;code = 105
char = c;code = 99
char = ;code = 32
char = d;code = 100
char = e;code = 101
char = t;code = 116
char = e;code = 101
char = r;code = 114
char = m;code = 109
char = i;code = 105
char = n;code = 110
char = a;code = 97
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = ;code = 32
char = (;code = 40
char = y;code = 121
char = );code = 41
char = ;code = 32
char = w;code = 119
char = i;code = 105
char = t;code = 116
char = h;code = 104
char = ;code = 32
char = a;code = 97
char = ;code = 32
char = c;code = 99
char = h;code = 104
char = r;code = 114
char = o;code = 111
char = m;code = 109
char = a;code = 97
char = t;code = 116
char = o;code = 111
char = g;code = 103
char = r;code = 114
char = a;code = 97
char = p;code = 112
char = h;code = 104
char = i;code = 105
char = c;code = 99
char = ;code = 32
char = p;code = 112
char = r;code = 114
char = o;code = 111
char = c;code = 99
char = e;code = 101
char = d;code = 100
char = u;code = 117
char = r;code = 114
char = e;code = 101
char = ;code = 32
char = (;code = 40
char = x;code = 120
char = );code = 41
char = ;code = 32
char = g;code = 103
char = a;code = 97
char = v;code = 118
char = e;code = 101
char = ;code = 32
char = y;code = 121
char = ;code = 32
char = =;code = 61
char = ;code = 32
char = 1;code = 49
char = .;code = 46
char = 0;code = 48
char = 2;code = 50
char = x;code = 120
char = ;code = 32
char = -;code = 45
char = ;code = 32
char = 0;code = 48
char = .;code = 46
char = 6;code = 54
char = 5;code = 53
char = 3;code = 51
char = ;code = 32
char = (;code = 40
char = S;code = 83
char = y;code = 121
char = l;code = 108
char = x;code = 120
char = ;code = 32
char = =;code = 61
char = ;code = 32
char = 3;code = 51
char = .;code = 46
char = 6;code = 54
char = 1;code = 49
char = );code = 41
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result sql = We present a method for measuring ascorbic acid in methanol/trichloroacetic acid extracts prepared from human plasma after enzymatic oxidation of ascorbic acid to dehydroascorbic acid by ascorbate oxidase. Samples were assayed by spectrophotometrically monitoring the kinetics of the concentration-dependent absorbance changes of dehydroascorbic acid with phosphate-citrate-methanol buffers. Ascorbic acid was determined as the difference between dehydroascorbic acid and total ascorbic acid content. The detection limit was < 0.5 mumol/L. The calibration curve was linear (r > 0.995) over the range 0-1000 mumol/L. Analytical recovery of ascorbic acid added to plasma was 93-105%. The between-day variance was < 7%. Comparison of the spectrophotometric determination (y) with a chromatographic procedure (x) gave y = 1.02x - 0.653 (Sylx = 3.61) over the range of physiologically relevant concentrations. Total analysis time is < 10 min per sample and allows the simultaneous analysis of multiple samples.

Publication: Clin. Chem. 1995 Aug ;41(8 Pt 1)::1177-81.
Publication Date: 1995 Aug
Study Author(s): Moeslinger, T;Brunner, M;Volf, I;Spieckermann, P G;
Institution: Institute for Medical Physiology, Vienna, Austria.
Shortcut link to this study:
We present a method for measuring ascorbic acid in methanol/trichloroacetic acid extracts prepared from human plasma after enzymatic oxidation of ascorbic acid to dehydroascorbic acid by ascorbate oxidase. Samples were assayed by spectrophotometrically monitoring the kinetics of the concentration-dependent absorbance changes of dehydroascorbic acid with phosphate-citrate-methanol buffers. Ascorbic acid was determined as the difference between dehydroascorbic acid and total ascorbic acid content. The detection limit was < 0.5 mumol/L. The calibration curve was linear (r > 0.995) over the range 0-1000 mumol/L. Analytical recovery of ascorbic acid added to plasma was 93-105%. The between-day variance was < 7%. Comparison of the spectrophotometric determination (y) with a chromatographic procedure (x) gave y = 1.02x - 0.653 (Sylx = 3.61) over the range of physiologically relevant concentrations. Total analysis time is < 10 min per sample and allows the simultaneous analysis of multiple samples.
PMID: 7628094

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