Determination of the radiochemical purity of (99m) Tc medronate injection by thin layer chromatography on iTLC-SG: effect of medronate concentration on the value measured.

Background: When using iTLC-SG thin layer chromatography plates to measure radiochemical impurities in (99m) Tc medronate, falsely high values were obtained for (99m) Tc pertechnetate impurity. Preliminary investigations indicated that the mass of (99m) Tc medronate applied to the plate influences the value.

Aim: The goal of this study was to determine if the concentration of medronate influences the value obtained for (99m) Tc pertechnetate impurity.

Effect of 99Tc on the radiochemical purity of 99mTc radiopharmaceuticals.

Objective: The longer the time between elutions of a technetium-99m (Tc) generator, the greater the Tc : Tc ratio in the eluate. Information is limited on how this affects the radiochemical purity (RCP) of Tc radiopharmaceuticals. The aim was to determine whether the RCPs of Tc radiopharmaceuticals are affected when prepared using Tc-pertechnetate from a generator that remained uneluted for 7 days.

Preparation of 99mTc radiopharmaceuticals: the effect on radiochemical purity of using sodium chloride injection from plastic ampoules that have been exposed to light.

Objective: To determine whether radiochemical purity is affected when 99mTc radiopharmaceuticals are prepared using sodium chloride injection from plastic ampoules that have been exposed to light.

Methods: Sodium chloride injection from plastic ampoules that were either exposed to light for 7 days or protected from light was used in the preparation of nine common 99mTc radiopharmaceuticals: albumin nanocolloid, exametazime, macrosalb, mebrofenin, medronate, pentetate, sestamibi, succimer and tetrofosmin. Five different batches of ampoules (exposed and unexposed) were used for each radiopharmaceutical.

Preparation of 99m Tc-MAG3: the effect on radiochemical purity of using sodium chloride injection from plastic ampoules that have been exposed to light.

Objective: To determine the circumstances under which sodium chloride injection (SCI) that has been exposed to fluorescent light then used to prepare 99m Tc-MAG3 causes low radiochemical purity (RCP).

Methods: Two brands of SCI in plastic ampoules (Braun and Steri-Amp) and one in glass vials (Drytec) were exposed to light for up to 7 days then used to prepare 99m Tc-MAG3. RCP was measured by liquid chromatography.

Preparation of 99mTc-Nanocoll for use in sentinel node localization: Validation of a protocol for supplying in unit-dose syringes.

Objectives: To determine if 99mTc-Nanocoll is affected by storage in a syringe, passage through an R-Lock or mixing with Patent Blue V dye.

Methods: A Nanocoll kit was reconstituted at 280 MBq/5 ml. Samples of 0.

The adaptive response of the reticuloendothelial system to major liver resection in humans.

Objective: To evaluate the contribution of the liver to total circulatory reticuloendothelial system (RES) phagocytosis capacity in patients undergoing liver resection and to compare it with values in end-stage chronic liver disease.

Summary Background Data: The mechanism whereby major liver resection is associated with a high incidence of infection is unknown. Significant impairment of RES phagocytosis has been described in liver failure, rendering such patients susceptible to infection; and we hypothesized that similar impairment might occur following major liver resection.

Preparation of 99mTc-MAG3: radiochemical purity is affected by the residence time of sodium chloride injection in a three-part syringe.

Background: Routine technetium-99m mercaptoacetyltriglycine (99mTc-MAG3) radiochemical purity measurements have revealed occasional unacceptably low values. Preliminary investigations suggested a causal link with the residence time of sodium chloride injection in the syringe used to reconstitute the MAG3 kit.

Objectives: To investigate the cause of this phenomenon, determine how it can be avoided and establish whether it occurs with other 99mTc radiopharmaceuticals.

Do inhaled carbon nanoparticles translocate directly into the circulation in humans?

Rationale: Increased exposure to particulate air pollution (PM(10)) is a risk factor for death and hospitalization with cardiovascular disease. It has been suggested that the nanoparticulate component of PM(10) is capable of translocating into the circulation with the potential for direct effects on the vasculature.

Objective: The study's aim was to determine the extent to which inhaled technetium-99m ((99m)Tc)-labeled carbon nanoparticles (Technegas) were able to access the systemic circulation.

A comparison of techniques for analysing 90Y-Zevalin thin-layer chromatography plates.

Objectives: To simulate 90Y-Zevalin thin-layer chromatograms representing a range of radiochemical purities, to compare the radiochemical purities obtained with five techniques used to quantify 90Y on the plates and to measure the reproducibility of the five techniques at the minimum acceptable radiochemical purity of 95%.

Methods: Yttrium-90 solutions were pipetted onto the origin and solvent front lines of thin-layer chromatography (TLC) plates to simulate radiochemical purities of 90%, 92%, 94%, 95%, 96%, 98% and 100%. Each plate was analysed using three TLC scanners (Bioscan AR2000, Bioscan Mini-scan and an instrument constructed in-house) and two cut-and-count techniques: one using a sodium iodide well detector and the other a liquid scintillation counter.

A comparison of SepPak and high-performance liquid chromatography as techniques for measuring the radiochemical purity of 99mTc-MAG3.

Objective: To compare high-performance liquid chromatography and SepPak as techniques for measuring the radiochemical purity of 99mTc-MAG3.

Methods: Samples of 99mTc-MAG3 (n = 20) with radiochemical purities in the range 43-98% were prepared and analysed by both techniques.

Results: The correlation between the results from the two techniques was excellent (r = 1.