Serum acid glycoprotein

Proteins. A chiral stationary phase with immobilized a -acid glycoprotein on silica beads was introduced by Hermansson in 1983 [18, 19]. Several other proteins such as chicken egg albumin (ovalbumin), human serum albumin, and cellohy-drolase were also used later for the preparation of commercial CSPs. Their selectivity is believed to occur as a result of excess of dispersive forces acting on the more retained enantiomer [17]. These separation media often exhibit only modest loading capacity. 

CRP , complement , PLA2 , serum amyloid A , fibrinogen , c -acid glycoprotein , IL-1Ra , ceruloplasmin , ai-antichymotrypsin , LBP albumin , haptoglobin , IGF-1 , transferrin , u2-HS glycoprotein ... 

Bovine serum albumin covalently bonded to silica and a-acid glycoprotein immobilized on silica have been used to resolve a wide range of acidic and basic drugs and amino acid derivatives [807-810]. Because of their complex structures, however, the... 

There is a wide variety of commercially available chiral stationary phases and mobile phase additives.32 34 Preparative scale separations have been performed on the gram scale.32 Many stationary phases are based on chiral polymers such as cellulose or methacrylate, proteins such as human serum albumin or acid glycoprotein, Pirkle-type phases (often based on amino acids), or cyclodextrins. A typical application of a Pirkle phase column was the use of a N-(3,5-dinitrobenzyl)-a-amino phosphonate to synthesize several functionalized chiral stationary phases to separate enantiomers of... 

Bovine serum albumin Oii-Acid glycoprotein Bovine serum albumin Teicoplanin (Chirobtiotic T) Napthylurea Napthylurea... 

Bovine serum albumin oq-Acid glycoprotein Bovine serum albumin Chiracel OJ-R... 

Body composition 1 Total body water 1 Lean body mass T Body fat or i Serum albumin <-> or T -Acid glycoprotein (T by several disease states)... 

The use of triphenylethylene SERMs as Pgp inhibitors for clinical application has been hampered by unacceptable toxicity at doses required to achieve adequate cellular concentration, which is likely due to the involvement of proteins with the ability to bind these compounds. For instance, toremifene is able to reverse MDR and to sensitize human renal cancer cells to vinblastine in vitro. However, in vivo toremifene is tightly bound to serum proteins, in particular a 1-acid glycoprotein (AAG), which may limit its tissue availability (Braybrooke et al. 2000). In agreement with this, Chatterjee and Harris (1990) have shown that tamoxifen and 4-OH-tamoxifen were similarly potent in reversing MDR in Chinese hamster ovary (CHO) cells with acquired resistance to adriamycin. However, the addition of AAG (0.5 to 2 mg/ml, the range found in vivo) to cell cultures decreased the effect of tamoxifen on reversing MDR, and at the highest AAG concentration there was a complete reversal of the effects of... 

Chiral stationary phases for the separation of enantiomers (optically active isomers) are becoming increasingly important. Among the first types to be synthesized were chiral amino acids ionically or covalently bound to amino-propyl silica and named Pirkle phases after their originator. The ionic form is susceptable to hydrolysis and can be used only in normal phase HPLC whereas the more stable covalent type can be used in reverse phase separations but is less stereoselective. Polymeric phases based on chiral peptides such as bovine serum albumin or a -acid glycoproteins bonded to... 

There have been several studies that underscore the importance of unbound concentration in cell-based studies of receptor function. In a model study of the effect of plasma protein binding on the renal transport of organic anions using the expression of various organic anion transporters (OATPs) in Xenopus oocytes, the transport of ochratoxin A, methotrexate, and estrone sulfate was found to be strongly inhibited by the addition of human serum albumin to the culture medium [16]. Similarly, the addition of oq-acid glycoprotein was found to reverse the blockade of sodium-ion current by cocaine in a preparation of cardiac myocytes [17]. 

The unbound fraction of the epidermal growth factor receptor tyrosine kinase inhibitor gefitinib has been extensively studied in cancer patients [39]. The drug was found to bind to serum albumin, oq-acid glycoprotein, and red blood cells with a mean unbound fraction of 3.4% which was constant over 28 days of dosing. Unbound fraction ranged from 2.2% to 5.4% and was inversely correlated with pre-treatment levels of oq-acid glycoprotein. 

Pharmacokinetics Ticlopidine is rapidly absorbed (more than 80%), with peak plasma levels occurring at approximately 2 hours after dosing, and is extensively metabolized. Administration after meals results in a 20% increase in the area under the plasma concentration-time curve (AUC). Ticlopidine displays nonlinear pharmacokinetics and clearance decreases markedly on repeated dosing. Ticlopidine binds reversibly (98%) to plasma proteins, mainly to serum albumin and lipoproteins. The binding to albumin and lipoproteins is nonsaturable over a wide concentration range. Ticlopidine also binds to alpha-1 acid glycoprotein at concentrations attained with the recommended dose, 15% or less in plasma is bound to this protein. 

Primarily bound to human serum albumin and alpha-] acid glycoprotein over the ritonavir concentration range of 0.01 to 30 mcg/mL. 

Distribution - The mean volume of distribution is 12 L/kg. Sirolimus is extensively bound (approximately 92%) to human plasma proteins. The binding of sirolimus was shown mainly to be associated with serum albumin (97%), - -acid glycoprotein, and lipoproteins. The majority of sirolimus is... 

Bezkorovainy, A. 1965. Comparative study of the acid glycoproteins isolated from bovine serum colostrum and milk whey. Arch. Biochem. Biophys. 110, 558-567. 

Proteins, amino acids bonded through peptide linkages to form macromolecular biopolymers, used as chiral stationary phases for hplc include bovine and human serum albumin, OL-acid glycoprotein, ovomucoid, avidin, and cellobiohydrolase. The bovine serum albumin column is marketed under the name Resolvosil and can be obtained from Phenomenex. The human serum albumin column can be obtained from Alltech Associates, Advanced Separation Technologies, Inc., and J. T. Baker. The a1-acid glycoprotein and cellobiohydrolase can be obtained from Advanced Separation Technologies, Inc. or J. T. Baker, Inc. 

Proteins have also been used as CMPAs for chiral resolution by liquid chromatography. Bovine serum albumin (BSA) and a]-acid glycoproteins (AGP) were investigated as CMPAs. Allenmark et al. [87] used BSA protein as the CMPA for... 

---