Pilot trial of genetically modified, attenuated Salmonella expressing the E. coli cytosine deaminase gene in refractory cancer patients

We performed a pilot trial in refractory cancer patients to investigate the feasibility of intratumoral injection of TAPET-CD, an attenuated Salmonella bacterium expressing the E. coli cytosine deaminase gene. A total of three patients received three dose levels of TAPET-CD (3 x 10(6)-3 x 10(7) CFU/m(2)) via intratumoral injection once every 28 days as long as progression of disease or intolerable toxicity was not observed. From days 4 to 14 of each 28 day cycle, patients also received 5-fluorocytosine (5-FC) at a dose of 100 mg/kg/day p.o. divided three times daily. Six cycles of treatment were administered. No significant adverse events clearly attributable to TAPET-CD were demonstrated. Two patients had intratumor evidence of bacterial colonization with TAPET-CD, which persisted for at least 15 days after initial injection. Conversion of 5-FC to 5-fluorouracil (5-FU) as a result of cytosine deaminase expression was demonstrated in these two patients. The tumor to plasma ratio of 5-FU for these two colonized patients was 3.0, demonstrating significantly increased levels of 5-FU at the site of TAPET-CD colonization and insignificant systemic spread of the bacteria. In contrast, the tumor to plasma ratio of 5-FU of the patient who did not show colonization of TAPET-CD was less than 1.0. These results support the principle that a Salmonella bacterium can be utilized as a delivery vehicle of the cytosine deaminase gene to malignant tissue and that the delivered gene is functional (i.e. able to convert 5-FC to 5-FU) at doses at or below 3 x 10(7) CFU/m(2).

Hydrophilic interaction chromatography using amino and silica columns for the determination of polar pharmaceuticals and impurities

Hydrophilic interaction chromatography (HILIC) is described as a useful alternative to reversed-phase chromatography for applications involving polar compounds. In the HILIC mode, an aqueous-organic mobile phase is used with a polar stationary phase to provide normal-phase retention behavior. Silica and amino columns with aqueous-acetonitrile mobile phases offer potential for use in the HILIC mode. An examination of the retention and separation of several pyrimidines, purines, and amides on silica and amino columns from three manufacturers revealed that mobile phases should contain a buffer or acid for pH control to achieve similar and reproducible results among columns from different sources. Amino columns may also be used in an anion-exchange mode, which provides an advantage for some applications. In some cases, silica can provide different selectivity and better separation than an amino column. Example applications include: low-molecular-mass organic acids and amides as impurities in non-polar drug substances, 5-fluorouracil in 5-fluorocytosine, guanine in acyclovir, and different selectivity for polar basic compounds compared to an ion-pairing system.

Occupational exposure to antineoplastic agents at several departments in a hospital. Environmental contamination and excretion of cyclophosphamide and ifosfamide in urine of exposed workers

The occupational exposure to cyclophosphamide (CP), ifosfamide (IF), 5-fluorouracil (5FU), and methotrexate (MTX) of 25 pharmacy technicians and nurses from four departments of a hospital was investigated. Previously developed methods for the detection of exposure to some antineoplastic agents were validated. Exposure to CP, IF, 5FU, and MTX was measured by the analysis of these compounds in the environment (air samples and wipe samples from possible contaminated surfaces and objects). Contamination of the work environment was found not only on the working trays of the hoods and on the floors of the different rooms but also on other objects like tables, the sink unit, cleaned urinals and chamber pots, and drug vials and ampules used for preparation and packing of drugs. The gloves used during preparation of the drugs and during cleaning of the hoods were always contaminated. The uptake of CP or IF was determined by the analysis of both compounds in urine. CP or IF was detected in the urine of eight pharmacy technicians and nurses. The amounts ranged from less than 0.01 to 0.5 micrograms (median: 0.1 microgram). CP and IF were found not only in the urine of pharmacy technicians and nurses actively handling these compounds (n = 2) but also in the urine of pharmacy technicians and nurses not directly involved in the preparation and administration of these two drugs (n = 6). CP and IF were excreted during different periods ranging from 1.40 to 24.15h after the beginning of the working day, suggesting different times of exposure, different exposure routes, and/or interindividual differences in biotransformation and excretion rate for these compounds.(ABSTRACT TRUNCATED AT 250 WORDS)

Surface contamination with antineoplastic agents in six cancer treatment centers in Canada and the United States

The level of contamination by antineoplastic agents in drug preparation and administration areas in cancer treatment centers in Canada and the United States was determined. Sampling locations at three cancer treatment centers in Canada and three centers in the United States were selected (biological safety cabinets, countertops, and floors in and adjacent to preparation areas; tabletops, chairs, and floors in administration areas). A solution of sodium hydroxide (0.03 M) was spread over the surface of each area. The surface was wiped with one or two absorbent tissues, which were then stored in plastic screw-top containers. Samples were stored at -40 degrees C before analysis of ifosfamide content (U.S. centers only) and cyclophosphamide content by gas chromatography in tandem with mass spectroscopy-mass spectroscopy and fluorouracil content by reverse-phase high-performance liquid chromatography with ultraviolet-light detection. Measurable amounts of the antineoplastic agents were detected in 75% of the pharmacy samples and 65% of the administration samples. In general, the levels of contamination were higher in the pharmacy areas than in the drug administration areas. The pharmacy area at the site with the highest number of drug preparations had considerably more drug contamination than the other sites. The results were similar for Canadian and U.S. centers. Substantial levels of contamination from three antineoplastic agents were detected on a variety of surfaces in pharmacy drug preparation areas and drug administration areas in six cancer treatment centers in Canada and the United States.

Reduction in surface contamination with antineoplastic drugs in 22 hospital pharmacies in the US following implementation of a closed-system drug transfer device

PURPOSE

Surface contamination with the antineoplastic drugs cyclophosphamide, ifosfamide, and 5-fluorouracil was compared in 22 US hospital pharmacies following preparation with standard drug preparation techniques or the PhaSeal® closed-system drug transfer device (CSTD).

METHODS

Wipe samples were taken from biological safety cabinet (BSC) surfaces, BSC airfoils, floors in front of BSCs, and counters and analyzed for contamination with cyclophosphamide, ifosfamide, and 5-fluorouracil. Contamination was reassessed several months after the implementation of the CSTD. Surface contamination (ng/cm(2)) was compared between the two techniques and evaluated with the Signed Rank Test.

RESULTS

Using the CSTD compared to the standard preparation techniques, a significant reduction in levels of contamination was observed for all drugs (cyclophosphamide: p < 0.0001; ifosfamide: p < 0.001; 5-fluorouracil: p < 0.01). Median values for surface contamination with cyclophosphamide, ifosfamide, and 5-fluorouracil were reduced by 95%, 90%, and 65%, respectively.

CONCLUSIONS

Use of the CSTD significantly reduces surface contamination when preparing cyclophosphamide, ifosfamide, and 5-fluorouracil as compared to standard drug preparation techniques.

Analytical detection and biological assay of antileukemic drug 5-fluorouracil using gold nanoparticles as probe

Gold nanoparticles are reported and evaluated as probes for the detection of anticancer drug 5-fluorouracil (5FU). The nature of binding between 5FU and gold nanoparticles via complexation is investigated using ultraviolet visible spectrophotometry, cyclic voltammetry, transmission electron microscopy, fluorescence and Fourier transform infrared (FTIR) spectroscopy. The bound antileukemic drug is fluorescent and the quenching property of gold nanoparticles could be exploited for biological investigations. The 5FU-colloidal gold complex (Au@5FU) is observed to have appreciable antibacterial and antifungal activity against Micrococcus luteus, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Aspergillus fumigatus, and Aspergillus niger. The experimental studies suggest that gold nanoparticles have the potential to be used as effective carriers for anticancer drugs.

In vitro release of 5-fluorouracil with cyclic core dendritic polymer

This paper describes the first synthesis of a series of dendritic polymers with a core of 1,4,7,10-tetraazacyclododecane. This core was allowed to react with methyl acrylate through a Michael addition and was then amidated with ethylenediamine. Repeating the two steps led to controlled molecular weight increasing and branching on the molecular level and produced four direction poly(amide-amine) dendrimers. We successfully synthesized dendrimers from generation 0. 5 to generation 5.5. Each generation was analyzed by Fourier- transform infrared (FT-IR) spectroscopy, 1H NMR and elemental analysis. Titrimetry was also used to determine the number of -NH2 of each full generation (2.0, 3.0, 4.0, 5.0). SEC (size exclusion chromatography) was performed to test the purity of G-3.0, G-4.0 and G-5.0. Parts of the outer layer -NH2 groups of the dendrimers generation 4 and generation 5 were acylated by acetic anhydride. The solubility in water of the dendrimer was thus greatly enhanced. The acetylated dendrimers were then reacted with 1-bromoacetyl-5-fluorouracil to form dendrimer-5FU conjugates. Hydrolysis of the conjugates in a phosphate buffer solution (pH 7.4) at 37 degreesC will release free 5FU. Different generation of dendrimer-5FU conjugates exert marking influence on the amount of 5FU released. The dendritic polymer seems to be a promising carrier for the controlled release of antitumor drugs.

Mass flows of X-ray contrast media and cytostatics in hospital wastewater

Little is known about the significance of hospitals as point sources for emission of organic micropollutants into the aquatic environment. A mass flow analysis of pharmaceuticals and diagnostics used in hospitals was performed on the site of a representative Swiss cantonal hospital. Specifically, we analyzed the consumption of iodinated X-ray contrast media (ICM) and cytostatics in their corresponding medical applications of radiology and oncology, respectively, and their discharge into hospital wastewater and eventually into the wastewater of the municipal wastewater treatment plant. Emission levels within one day and over several days were found to correlate with the pharmacokinetic excretion pattern and the consumed amounts in the hospital during these days. ICM total emissions vary substantially from day to day from 255 to 1259 g/d, with a maximum on the day when the highest radiology treatment occurred. Parent cytostatic compounds reach maximal emissions of 8-10 mg/d. A total of 1.1%, 1.4%, and 3.7% of the excreted amounts of the cytostatics 5-fluorouracil, gemcitabine, and 2',2'-difluorodeoxyuridine (main metabolite of gemcitabine), respectively, were found in the hospital wastewater, whereas 49% of the total ICM was detected, showing a high variability among the compounds. These recoveries can essentially be explained by the high amount administered to out-patients (70% for cytostatics and 50% for ICM); therefore, only part of this dose is expected to be excreted on-site. In addition, this study emphasizes critical issues to consider when sampling in hospital sewer systems. Flow proportional sampling over a longer period is crucial to compute robust hospital mass flows.

Determination of 5-fluorouracil in hospital effluents

Cytostatic anticancer drugs are an increasingly important issue in the environmental debate, mainly due to the lack of knowledge about the fate of these toxic substances. Over the last decades, 5-fluorouracil (5-FU) has been one of the most frequently used antineoplastic agents and may, therefore, be regarded as one of the pilot substances for environmental contamination. As a prerequisite for these investigations, a method for the determination of 5-FU in hospital effluents has been developed. Waste water samples were enriched by solid-phase extraction on ENV(+) columns (concentration factor 500) and analysed by capillary electrophoresis using a buffer containing 80% 160 mM sodium borate buffer (pH 9.5) and 20% acetonitrile (v/v). This method is applicable within the range 5-500 microg 5-FU L(-1). The standard curve (correlation coefficient >0.99) was linear with recovery rates from 80 to 96% and an accuracy from 9.0 to 20% (intra-assay standard deviation 0.7-8.9%; inter-assay standard deviation 2.2-9.5%). Based on the consumption of 5-FU in oncologic departments and the detection limit of 1.7 microg L(-1), this method covers the range necessary to evaluate 5-FU in hospital effluents. The applicability of the method was proven by chemical analysis of real hospital waste water samples. Obtained over a time period of 1 month (range 20-122 microg 5-FU L(-1)), the results were similar to those calculated by an input-output model. The presented method provides an analytical tool necessary to face the monitoring of environmental contamination problems.

Genetically engineered Bifidobacterium longum for tumor-targeting enzyme-prodrug therapy of autochthonous mammary tumors in rats

A fundamental obstacle in systemic therapy for cancer patients is the specific targeting of therapy directly to solid tumors. A strain of the domestic bacterium Bifidobacterium longum, which is non-pathogenic and anaerobic, showed selective localization to and proliferation within solid tumors after systemic application. Here, we propose a novel approach to cancer gene therapy in which anaerobic and non-pathogenic bacteria of the genus B. longum are used to achieve tumor-specific gene delivery and enzyme-prodrug therapy. We constructed a plasmid, pBLES100-S-eCD, which included eCD. Transfected B. longum produced CD in hypoxic tumors and achieved tumor site-specific conversion of 5-FC to 5-FU. Furthermore, we demonstrated antitumor efficacy in rat bearing autochthonous mammary tumors injected with the transfected B. longum directly or intravenously. This method was confirmed to be effective for enzyme-prodrug therapy not only by intratumoral injection but also by systemic administration. To estimate the toxicity of this bacterial vector, the systemic immunogenicity was evaluated by ASA reaction and the anaphylactic activity of IgG was evaluated by PCA reaction in guinea pigs. In the ASA reaction, no anaphylaxis symptoms were observed in any immunized guinea pigs injected with transfected B. longum. In the PCA reaction, B. longum/S-eCD specific-PCA-induced antibody was not detected. Thus, we proposed that anaerobic bacteria of the genus B. longum were an attractive and safe tumor-targeting vector and transfected B. longum was a potential anticancer agent that could effectively and specifically treat solid tumors.

Fluorine-19 or phosphorus-31 NMR spectroscopy: A suitable analytical technique for quantitative in vitro metabolic studies of fluorinated or phosphorylated drugs

Fluorine-19 or phosphorus-31 NMR (19F NMR or 31P NMR) spectroscopy provides a highly specific tool for identification of fluorine- or phosphorus-containing drugs and their metabolites in biological media as well as a suitable analytical technique for their absolute quantification. This article focuses on the application of in vitro 19F or 31P NMR to the quantitative metabolic studies of some fluoropyrimidine or oxazaphosphorine drugs in clinical use. The first part presents an overview of the advantages (non-destructive and non-selective direct quantitative study of the biological matrices) and limitations (expensive cost of the spectrometers, limited mass or concentration sensitivity) of NMR spectroscopy. The second part deals with the criteria to be considered for successful quantification by NMR (uniform excitation over the entire spectral width of the spectrum, resonance signals properly characterised by taking into account T1 values and avoiding NOE enhancements, optimisation of the data processing, choice of a suitable standard reference). The third and fourth parts report some examples of quantification of 5-fluorouracil, its prodrug capecitabine, 5-fluorocytosine and their metabolites in bulk solutions (biofluids, tissue extracts, perfusates and culture media) and heterogeneous media (excised tissues and packed intact cells) as well as cyclophosphamide and ifosfamide in biofluids. These two parts emphasise the high potential of in vitro 19F or 31P NMR for absolute quantification, in a single run, of all the fluorine- or phosphorus-containing species in the matrices analysed. The limit of quantification in bulk solutions is 1-3 microM for 19F NMR and approximately 10 microM for 31P NMR. In heterogeneous media analysed with 19F NMR, it is 2-5 nmol in excised tissues and cell pellets.

Further study of nebulisation chemotherapy, a new chemotherapeutic method in the treatment of lung carcinomas: fundamental and clinical

Nebulisation chemotherapy, a chemotherapeutic method for the treatment of lung cancer that involves the administration of anticancer agents through the inhalation of nebulised aerosols, has been found to be highly effective (Tatsumura et al., 1983a,b). We confirmed that 5-FU administered by this method accumulates in the trachea, bronchi and regional lymph nodes of patients treated before surgery, along with 5-FU metabolites, FUR and FUdR, indicating that 5-FU is directly incorporated and metabolised in the respiratory tract. Parallel result were obtained using mongrel dogs. The 5-FU levels in other organs, such as the heart and liver, were found to be extremely low. Only a trace of 5-FU was found in the serum of both the patients and the dogs. We further investigated the anti-tumour effect of this therapy in ten selected patients and observed a satisfactory anti-tumour response of 60.0%. These results, along with our previous finding that the retention time of isotope tracers inhaled as aerosol is considerably longer in tumour tissues than in normal parts (Tatsumura et al., 1983a) explain the high antitumour action of this therapy and the absence of adverse effects of administered 5-FU.

Comparison of surface contamination with cyclophosphamide and fluorouracil using a closed-system drug transfer device versus standard preparation techniques

PURPOSE

A comparison was conducted of the levels of surface contamination with two commonly used antineoplastic drugs, cyclophosphamide and fluorouracil, on countertops, floors, and hood surfaces in three oncology pharmacies following preparation with standard hazardous drug (HD) preparation techniques, or a closed-system drug transfer device (CSTD) in conjunction with standard HD preparation techniques, or a CSTD in conjunction with standard HD preparation techniques but prepared on a countertop outside the biological safety cabinet (BSC).

METHODS

Wipe samples of the various surfaces in each pharmacy were obtained biweekly for 12 weeks (six samples) to establish a baseline. Following implementation of the CSTD, an additional six biweekly samples were collected. The CSTD was then removed, and a final six samples were collected again using standard preparation techniques. During the CSTD Phase, fluorouracil was prepared on the countertop outside the BSC.

RESULTS

During the 36-week study, 342 samples were collected. A total of 8% positive fluorouracil wipe samples were found in the three pharmacies. The proportion of positive fluorouracil samples was significantly less in the CSTD Phase than in the control phases (p = 0.0002). There were 324 (95%) positive cyclophosphamide wipe samples. The median surface contamination was significantly different across the three phases (p < 0.00001). This was consistent at all sites, for both the BSC work surfaces and countertops. Contamination on floors adjacent to the BSCs was not consistently reduced.

CONCLUSION

The use of a CSTD in the BSC in conjunction with standard HD preparation techniques significantly reduced cyclophosphamide surface contamination as compared to standard techniques alone. Preparation of fluorouracil outside the BSC using the CSTD did not result in significant analytically detectable contamination on the countertops.

Determination of S-1 (combined drug of tegafur, 5-chloro-2,4-dihydroxypyridine and potassium oxonate) and 5-fluorouracil in human plasma and urine using high-performance liquid chromatography and gas chromatography-negative ion chemical ionization mass spectrometry

A high-performance liquid chromatography (HPLC) and gas chromatography-negative ion chemical ionization mass spectrometry (GC-NICI-MS) method was developed for the analysis of the combined antitumor drug S-1 (tegafur, 5-chloro-2,4-dihydroxypyridine and potassium oxonate) and active metabolite 5-fluorouracil in human plasma and urine. Tegafur was fractionated from biological fluids by extraction with dichloromethane and analyzed by HPLC. 5-Fluorouracil and 5-chloro-2,4-dihydroxypyridine were extracted with ethyl acetate from the residual layer after extraction of tegafur, and converted to pentafluorobenzyl (PFB) derivatives. Potassium oxonate was cleaned up with an anion-exchange column (Bond Elut NH2). The extracted potassium oxonate was degraded to 5-azauracil and converted to PFB derivatives. The PFB derivatives were analyzed by GC-NICI-MS. A stable isotope was employed as the internal standard in the GC-NICI-MS analysis. The limits of quantitation of tegafur, 5-fluorouracil, 5-chloro-2,4-dihydroxypyridine and potassium oxonate in plasma were 10, 1, 2 and 1 ng/ml, respectively. The reproducibility of the analytical method according to the statistical coefficients is approximately 10%. The accuracy of the method is good; that is, the relative error is < 10%. The methods were applied to pharmacokinetic studies of S-1 in patients.

Characterization of 5-fluorouracil microspheres for colonic delivery

The purpose of this investigation was to prepare and evaluate the colon-specific microspheres of 5-fluorouracil for the treatment of colon cancer. Core microspheres of alginate were prepared by the modified emulsification method in liquid paraffin and by cross-linking with calcium chloride. The core microspheres were coated with Eudragit S-100 by the solvent evaporation technique to prevent drug release in the stomach and small intestine. The microspheres were characterized by shape, size, surface morphology, size distribution, incorporation efficiency, and in vitro drug release studies. The outer surfaces of the core and coated microspheres, which were spherical in shape, were rough and smooth, respectively. The size of the core microspheres ranged from 22 to 55 microm, and the size of the coated microspheres ranged from 103 to 185 microm. The core microspheres sustained the drug release for 10 hours. The release studies of coated microspheres were performed in a pH progression medium mimicking the conditions of the gastrointestinal tract. Release was sustained for up to 20 hours in formulations with core microspheres to a Eudragit S-100 coat ratio of 1:7, and there were no changes in the size, shape, drug content, differential scanning calorimetry thermogram, and in vitro drug release after storage at 40 degrees C/75% relative humidity for 6 months.

The use of 19F spectroscopy and diffusion-weighted MRI to evaluate differences in gene-dependent enzyme prodrug therapies

To evaluate noninvasive measures of gene expression and tumor response in a gene-dependent enzyme prodrug therapy (GDEPT), a bifunctional fusion gene between Saccharomyces cerevisiae cytosine deaminase (CD) and Haemophilus influenzae uracil phosphoribosyltransferase (UPRT) was constructed. CD deaminates 5-fluorocytosine (5FC) to 5-fluorouracil (5FU), and UPRT subsequently converts 5FU to fluorouridine monophosphate, and both of these reactions can be monitored noninvasively in vitro and in vivo using 19F magnetic resonance spectroscopy (MRS). Following transient transfection the CD-UPRT fusion protein exhibited both UPRT and CD enzymatic activities as documented by 19F MRS. In addition, an increase in CD activity and thermal stability was witnessed for the fusion protein compared to native CD. Stable expression of CD-UPRT in 9L glioma cells increased both 5FC and 5FU sensitivity in vitro compared to CD-expressing and wild-type 9L cells. Noninvasive 19F MRS of both CD and UPRT gene function in vivo demonstrated that in animals bearing CD-expressing tumors there was limited conversion of 5FC to 5FU with no measurable accumulation of cytotoxic fluorinated nucleotides (F-nucs). In contrast, CD-UPRT-expressing tumors had increased CD gene activity with a threefold higher intratumoral accumulation of 5FU and significant generation of F-nucs. Finally, CD-UPRT yielded increased efficacy in an orthotopic animal model of high-grade glioma. More importantly, early changes in cellular water mobility, which are felt to reflect cellular death, as measured by diffusion-weighted MRI, were predictive of both durable response and increased animal survival. These results demonstrate the increased efficacy of the CD-UPRT GDEPT compared to CD alone both biochemically and in a preclinical model and validate both 19F MRS and diffusion-weighted MRI as tools to assess gene function and therapeutic efficacy.

The nature of the oil phase and the release of solutes from multiple (w/o/w) emulsions

The effect of the nature of the oil phase of w/o/w emulsions stabilized by interfacial complexation between span 80 (sorbitan mono-oleate) and albumin has been studied. The long-term stability of the systems has been assessed by photomicrography and by measuring the quantity of an internal marker (NaCl) remaining entrapped with time. The number of multiple oil drops and the diameters of the internal aqueous droplets were determined over 6 weeks, and the amounts of NaCl entrapped over the same period were followed. There were no significant changes in w/o/w emulsions prepared with a range of hydrocarbons (octane, dodecane, hexadecane, toluene and cyclohexane), indicating stable multiple emulsions. The release of NaCl and 5-fluorouracil (5-FU) separately entrapped in the internal aqueous phase of w/o/w emulsions was measured. Diffusion of the un-ionized species of 5-FU across the oil phase or through localized thin oil lamellae is the primary transport mechanism. In the presence of surface active agents, water is solubilized in inverse micelles which would possess the ability to solubilize other water-soluble components, such as NaCl and 5-FU. The mixed inverse micellar units of Span 80 and polysorbate (Tween) 80 therefore act as solute carriers across the liquid hydrocarbon membrane separating the two aqueous phases of the emulsions. The main factor in determining the differences in rates of release from the hydrocarbon emulsions appears to be the droplet size of the internal aqueous phase.

Poly(butylcyanoacrylate) nanoparticles for topical delivery of 5-fluorouracil

Poly(butylcyanoacrylate) nanoparticles (PBCN) as a drug carrier of 5-fluorouracil (5FU) intended for topical treatment of skin lesia were investigated. The presence of 5FU (as saline solution, pH 10-11) in the polymerization medium affected the polymerization as well as the nanoparticle formation by influencing the initiation of the polymerization reaction. 5FU acted as an initiator in the anionic polymerization of n-butylcyanoacrylate monomer through its nucleophilic nitrogen centers. The results obtained by GPC, 1H NMR, and X-ray diffraction allude to a possible mechanism of cytostatic immobilization in the polymer matrix, with evidence for both free and bound forms of the drug.

Punctal-canalicular stenosis related to systemic fluorouracil therapy

This is, to our knowledge, the first report in the ophthalmic literature of punctal-canalicular stenosis and concomitant epiphora associated with the prolonged administration of fluorouracil; to our knowledge, fluorouracil is the first systemically administered agent to cause obstruction in the lacrimal system. Each of three patients receiving this antimetabolite alone and one patient receiving it in combination with methotrexate and cyclophosphamide were studied for complaints of epiphora. All four patients exhibited stenosis or occlusion of one or more puncta, while three also had one or four of their canaliculi stenosed. Two patients exhibited recurrent epiphora, beginning one to two days after each administration of fluorouracil and resolving in two to three days. One patient experienced amelioration of her symptoms after Silastic tube intubation of her canalicular system.

Surface-enhanced Raman spectral measurements of 5-fluorouracil in saliva

The ability of surface-enhanced Raman spectroscopy (SERS) to measure 5-fluorouracil (5-FU) in saliva is presented. The approach is based on the capacity of Raman spectroscopy to provide a unique spectral signature for virtually every chemical, and the ability of SERS to provide microg/mL sensitivity. A simple sampling method, that employed 1-mm glass capillaries filled with silver-doped sol-gels, was developed to isolate 5-FU from potential interfering chemical components of saliva and simultaneously provide SERSactivity. The method involved treating a 1 mL saliva sample with 1 mL of acetic acid, drawing 10 microL of sample into a SERS-active capillary by syringe, and then measuring the SER spectrum. Quality SER spectra were obtained for samples containing as little as 2 microg of 5-FU in 1 mL saliva. The entire process, the acid pretreatment, extraction and spectral measurement, took less than 5 minutes. The SERS of 5-fluorouridine and 5-fluoro-2'-deoxyuridine, two major metabolites of 5-FU, were also measured and shown to have unique spectral peaks. These measurements suggest that disposable SERS-active capillaries could be used to measure 5-FU and metabolite concentrations in chemotherapy patient saliva, thereby providing metabolic data that would allow regulating dosage. Tentative vibrational mode assignments for 5-FU and its metabolites are also given.

Determination of 5-fluorouracil in environmental samples by solid-phase extraction and high-performance liquid chromatography with ultraviolet detection

5-Fluorouracil (5-FU) is one of the most widely used antineoplastic drugs. It can be therefore considered to be a model compound for the identification of exposure routes during preparation and administration of cytostatic agents, especially for nucleoside analogue drugs. In this study, an HPLC-UV method was validated for determination of 5-FU in wipe samples by direct analysis of the aqueous solutions and in air samples by using solid-phase extraction (SPE). When samples were pre-treated on styrene-divinylbenzene resin SPE columns, a 20-fold preconcentration of the analyte was achieved. As regards air samples, correlation coefficients were always higher than 0.998 and the limit of detection was assessed at 15 ng on filter. In order to verify the reliability of these procedures, 5-chlorouracil was used as internal standard. The procedure presented here has been applied to the environmental monitoring of occupational exposed subjects. The amount of 5-FU ranged from 0.043 to 0.23 microg/m3 in air samples and from 0.2 to 470.1 microg/dm2 in wipe samples. 5-FU was also detected on the internal side of the gloves (0.07 to 3.77 microg/pair of gloves).

Hydrophilic interaction liquid chromatography–APCI–mass spectrometry determination of 5-fluorouracil in plasma and tissues

A simple and fast analytical method using hydrophilic interaction liquid chromatography (HILIC) coupled with mass spectrometry was developed to analyse 5-fluorouracil (5-FU) in plasma and tissues. The HILIC system overcomes problems reported in obtaining satisfactory retention of 5-FU with other types of HPLC systems. After addition of internal standard (IS) (5-Chlorouracil (5-CU)), plasma proteins were precipitated with acetonitrile, and tissue samples homogenised with a micro-dismembrator. The analysis was performed using a polymer-based column (Ashaipak NH2) and the compounds were eluted under gradient conditions at 1 ml/min using a mobile phase containing a mixture of ammonium formate and acetonitrile. MS detection used a API 4000 mass spectrometry with heated nebulizer source and multiple reaction monitoring operated in the negative ion mode. The mass transitions of 5-FU and its internal standard were 129 m/z-->42m/z and 145 m/z-->42 m/z, respectively. The lower limits of quantitation in plasma and tissues were about 5 ng/ml and 10 ng/g, respectively, using 25 microl of plasma and 50mg of tissue. Good linearity, accuracy and precision were obtained in all matrices tested. The suitability and robustness of the method for in vivo samples were confirmed by analysis of mouse plasma, muscle and tumour from animals dosed with 5-FU.