No abstract available.
Cyclosporine* ; Fluorescence Polarization Immunoassay* ; Fluorescence Polarization* ; Fluorescence*

A fluorescence polarization immunoassay (FPIA) was developed for the analysis ofaflatoxins (AFs) using an anti-aflatoxin B1 (AFB1) monoclonal antibody and a novel fluorescein-labeled AFB1 tracer. The FPIA showed an IC50 value of 23.33 ng/mL with a limit of detection of 13.12 ng/mL for AFB1. The cross-reactivities of AFB1, AFB2, AFG1, AFG2, AFM1, and AFM2 with the antibody were 100%, 65.7%, 143%, 23.5%, 111.4%, and 2%, respectively. The group-specificity of anti-AFB1mAb indicated that the FPIA could potentially be used in a screening method for the detection of total AFs, albeit not AFG2 and AFM2. The total time required for analyzing 96 samples in one microplate was less than 5 min. This study demonstrates the potential usefulness of the FPIA as a rapid and simple technique for monitoring AFs.
Aflatoxins ; analysis ; Fluorescence Polarization Immunoassay

BACKGROUND: The penetraton in vivo of topically applied substances can be assessed by physiological or pharmacalogical signs or analysed by chemical or histological techniques. In vitro absorption can be commonly quantitated by measuring the passage of a radioisotope-labelled substance across skin that has been mounted in a diffusion chamber. OBJECTIVE: Fluorescence polarization immunoassay technique has made the possible rapid growth of therapeutic drug nonitoring. We applied this methodology in measuring percutaneous absorption in a diffusion chamber. METHODS: We utilized sheets of whole epidermis prepared from the circumcised prepuce. Some epidermal sheets were treated with 2 ml of acetone for 2 minutes, and others not. The epidermal sheet was mounted in a diffusion chamber between the donor compartment for the penetrant and the receptor compartment containing saline. Lidocaine HC1(10 microgram/cm2) in vehicle(propylene glycol:ethanol; 7:3, vol/vol) was applied to the donor compartment for the penetrant. With flow rate of about 3 ml/h all of the receptor phase collected during 2 hours interval were quantitated for 10 hours by the fluorescence polarization immunoassay. RESULTS: Total absorption of lidocaine HC1 in the acetone-untreated group was 2.14+/-0.74% of the applied dose. Total absorption in the acetone-treated group showed no substantial difference (2.09+/-1.25%) compared to those of acetone-untreated group. The amount of lipid extracted from a epiderrnal sheet with acetone was 19+/-2.97%. CONCLUSION: Fluorescence polarization immunoassay may be a useful method in measuring percutaneous absorption in vitro.
Absorption ; Acetone ; Diffusion* ; Epidermis ; Fluorescence Polarization Immunoassay* ; Fluorescence Polarization* ; Fluorescence* ; Histological Techniques ; Humans ; Lidocaine ; Skin ; Skin Absorption* ; Tissue Donors

BACKGROUND: It was purposed to estimate correlation between fluorescence polarization immunoassay (FPIA) and high performance liquid chromatography (HPLC), and precision of individual methods. It was also objected to describe distribution of plasma total homocysteine in Korean adults. METHODS: The subjects were 100 adults admitted to Inha University Hospital during the month of October, 1998. The total plasma homocysteine concentration was measured by FPIA (IMx analyzer, Abbott Laboratories, IL, USA) and by HPLC (ACCLAIM Biogenic Amines Testing System, Bio-Rad Laboratories, CA, USA) using Bio-Rad Homocysteine. RESULTS: Plasma homocysteine levels (mean+/-SD) from Korean healthy adults by FPIA and HPLC were 9.75+/-3.80micromol/L, 7.72+/-3.36micromol/L, respectively. Plasma homocysteine levels according to sex by FPIA were 11.79micromol/L for male, 7.71micromol/L for female, and those by HPLC were 9.47micro mol/L for male, 5.98micromol/L for female, respectively. Intra-assay coefficient variations (CVs) of low, medium, and high concentration by FPIA are 1.83%, 0.47%, and 1.66%, and those by HPLC are 5.53%, 5.37%, and 4.56%, respectively. Inter-assay CVs of low, medium, and high concentration by FPIA are 2.28%, 1.44%, and 1.29%, and by HPLC are 7.23%, 5.54%, and 4.95%, respectively. CONCLUSION: Plasma homocysteine levels from male were significantly higher than female in Korean. Plasma homocysteine levels were increased according to increment of age. FPIA was more convenient, automatic, rapid, and reproducible than HPLC and also excellently correlated with HPLC. It is concluded that FPIA will potentially benefit for quantifying homocysteine in clinical laboratories.
Adult ; Biogenic Amines ; Chromatography, High Pressure Liquid ; Chromatography, Liquid* ; Female ; Fluorescence Polarization Immunoassay* ; Fluorescence Polarization* ; Fluorescence* ; Homocysteine* ; Humans* ; Male ; Plasma*

PURPOSE: To compare the antibiotic release kinetics of the implant coated with antibiotic-impregnated polymers MATERIALS AND METHODS: Authors used polylactic acid (PLA) and polylactic-co-glycolic acid (PLGA) as the biodegradable carriers, gentamicin sulfate as the antibiotic and Steinmann pin as the implant. Ten Steinmann pins were coated with gentamicin of each 10, 20 and 30% mixture of PLA or PLGA for the elution kinetics study. In the elution study, total 60 coated implants were incubated in 10 mL of phosphate buffered saline (PBS) at 37 delta C and sampled at 6 hrs, 1, 3, 6, 9, 12, 15, 20, and 25 days. Assays were performed with fluorescence polarization immunoassay. Statistical analysis was done with SAS release 2.01. RESULTS: Released concentration of GM decreased with time. Minimum inhibitory concentration was maintained until 6th day on PLA 10% subgroup, 9th day in the 20 and 30% subgroups, until 6th day on PLGA 20% subgroup, and 3rd day in the 10 and 30% subgroups. Released concentrations were significantly higher in all PLA subgroups than in PLGA as a parameter of sampled time (all p<0.05). There was no statistical difference between PLA 20 and 30% subgroup after 12th sampled day (p=0.2636). CONCLUSION: PLA-GM group showed higher effective concentration for longer time than PLGA-GM group. 20 and 30% subgroups of PLA-GM showed prolonged maintenance of minimum inhibitory concentration compared with 10% subgroup, but there was no difference between the two groups.
Fluorescence Polarization Immunoassay ; Gentamicins ; Kinetics* ; Microbial Sensitivity Tests ; Polymers*

In this symposium, we reviewed the principle and development of time-resolved fluorescence anisotropy measurement. Its method of measurement, characteristics and applications in the research of biomacromolecule, configuration and molecular structure have been discussed. Its potential applications are also illustrated.
Fluorescence Polarization ; methods ; Macromolecular Substances ; Mathematics ; Models, Molecular ; Time Factors

BACKGROUND: Cyclosporine dosing is traditionally based on trough levels(C0 level) rather than area under the concentration-time curve(AUC), although AUC correlates better with post transplantation acute rejection and acute toxicity. It is reported that C2 levels(2-hour postdose blood levels) are single sampling point that best reflects AUC0-4. But there has been no recommended C2 levels for patients after 12 months post kidney transplantation. The purpose of this study was to evaluate the correlation between C0 levels and C2 levels and define recommended target C2 levels in patients after 12 months post kidney transplantation. METHODS: Seventy three patients after 12 months post transplantation were studied. 83 data were obtained from 73 renal transplant patients. Blood C0 levels, blood C2 levels, body weight and serum creatinine level were measured. Blood cyclsporine levels were measured by monoclonal fluorescence polarization immunoassay(mFPIA)(TDX, Abbot). The data of C0 levels were divided into three groups : low group (mean+SD, 197.1 ng/mL). RESULTS: There was a positive correlation between C0 levels and C2 levels, but no correlation between C0 levels and C2 levels when C0 levels were divided into three groups. There was a positive correlation between cyclosporine/body weight and C2 levels in normal C0 group. Recommended C2 levels in normal C0 group is 724.7+/-210.1 ng/mL. CONCLUSION: It is assumed that cyclosporine doses can be individualized by using C2 levels rather than C0 levels in renal transplant patients. However, prospective study may be needed to confirm the improvement of longterm renal allograft survival by individualizing cyclosporine doses based on C2 levels.
Allografts ; Area Under Curve ; Body Weight ; Creatinine ; Cyclosporine* ; Fluorescence Polarization ; Humans ; Kidney Transplantation* ; Kidney*

OBJECTIVE: This study was conducted to confirm the results of the authors' previous research on schizophrenia manifesting high serum homocysteine and low folate levels. This study is anchored on a theory that a high serum homocysteine concentration affects schizophrenia by virtue of a neurotoxic mechanism, and on a report that some schizophrenia patients with high homocysteine levels benefited from high folate ingestion. METHODS: The serum homocysteine, folate, and vitamin B12 levels of 236 normal-control-group subjects and 234 schizophrenia subjects who met the diagnostic criteria based on DSM-IV-TR were compared. The homocysteine levels were measured via fluorescence polarization immunoassay, and the folate and vitamin B12 levels were determined via radioimmunoassay. RESULTS: The homocysteine levels of the patient group were significantly higher than those of the normal control group. The homocysteine level was more negatively correlated with the folate level in the schizophrenia group than in the control group. The percentages of female and male schizophrenia subjects manifesting high homocysteine levels were 33.8 and 51.5%, respectively. The percentage of schizophrenia subjects with low folate levels was 66.2%. In the low- and normal-folate-level groups, the patient group showed significantly higher homocysteine levels than the normal control group. The low-folate-level patient group particularly showed significantly higher homocysteine levels than the low-folate-level normal control group. CONCLUSION: Some schizophrenia patients with high serum homocysteine levels may have the genetic defect of having low folate serum levels. In such cases, folate ingestion may be a good management modality for clinical improvement.
Eating ; Female ; Fluorescence Polarization Immunoassay ; Folic Acid ; Homocysteine ; Humans ; Male ; Schizophrenia ; Virtues ; Vitamin B 12

BACKGROUND: Vancomycin assay was performed to evaluate the clinical significance of therapeutic drug monitoring (TDM) of vancomycin and to compare pharmacokinetic parameters of vancomycin in our patients with population pharmacokinetic parameters. METHODS: In seventy-eight patients (45 males, 33 females), vancomycin serum concentrations were measured by fluorescence polarization immunoassay. At steady-state, peak levels were obtained one hour postinfusion, and trough levels were obtained just before a next dose. And also predicted serum vancomycin levels were determined by CAPCIL program in all subjects and compared with measured values, respectively. All patients were divided into two groups. Sixty-two patients in group I had a creatinine concentration in serum of < or =1.2 mg/dL and sixteen patients in group IIhad abnormal renal function as defined by a creatinine concentration in serum of >1.2 mg/dL. Follow-up second vancomycin concentrations were measured in 22 of 78 patients several days after initial TDM and were compared with initial TDM results. RESULTS: Mean values of peak and trough vancomycin concentration were 30.1 and 10.4, and 37.3 and 14.5 microgram/mL in groups I, and II, respectively. Predicted mean values of those were 26.3 and 9.2, and 28.2 and 7.8 microgram/mL in groups I, and II, respectively. Statistically significant differences between predicted and measured values in peak levels of group I,and IIand in trough level of group IIwere observed (P<0.01). Dose modification were required in 13 (21%) of 62 patients with normal renal function, and in 9 (56%) of 16 patients with abnormal renal function. Among 79 paired samples with a trough value below 15 mg/L, there were no peaks greater than 40 mg/L except two samples. CONCLUSION: Significant differences were noted between predicted and measured serum vancomycin concentrations and so TDM of vancomycin is needed to obtain effective dose and interval of vancomycin. More data about measured peak and trough values should be collected to establish pharmacokinetic parameters of vancomycin in Korean population.
Creatinine ; Drug Monitoring* ; Fluorescence Polarization Immunoassay ; Follow-Up Studies ; Humans ; Male ; Vancomycin*

The aim of this study was to provide a basis for studying the molecular mechanism of pharmacological action of chlorhexidine digluconate. Fluorescence polarization of n- (9-anthroyloxy) stearic acid was used to examine the effect of chlorhexidine digluconate on differential rotational mobility of different positions of the number of membrane bilayer phospholipid carbon atoms. The six membrane components differed with respect to 2, 3, 6, 9, 12, and 16- (9-anthroyloxy) stearic acid (2-AS, 3-AS, 6-AS, 9-AS, 12-AS and 16-AP) probes, indicating different membrane fluidity. Chlorhexidine digluconate increased the rate of rotational mobility of hydrocarbon interior of the cultured Porphyromonas gingivalis outer membranes (OPG) in a dose-dependent manner, but decreased the mobility of surface region (membrane interface) of the OPG. Disordering or ordering effects of chlorhexidine digluconate on membrane lipids may be responsible for some, but not all of its bacteriostatic and bactericidal actions.
Carbon ; Chlorhexidine* ; Fluorescence Polarization ; Membrane Fluidity ; Membrane Lipids ; Membranes* ; Porphyromonas gingivalis ; Porphyromonas* ; Thiram