Gamma scintigraphy and biodistribution of ^99mTc‐cefotaxime sodium in preclinical models of bacterial infection and sterile inflammation

Abstract

(99m)Tc-cefotaxime sodium ((99m)Tc-CEF) was developed and standardized under varying conditions of reducing and antioxidant agent concentration, pH, radioactivity dose, and reducing agent type. Labeling studies were performed by changing the selected parameters one by one, and optimum labeling conditions were determined. After observing the conditions for maximum labeling efficiency and stability, lyophilized freeze dry kits were prepared accordingly. Simple method for radiolabeling of CEF with (99m)Tc has been developed and standardized. Labeling efficiency of (99m)Tc-CEF was assessed by both radio thin-layer chromatography and radio high-performance liquid chromatography and found higher than 90%. The labeled compound was found to be stable in saline and human serum up to 24 h. Two different freeze dry kits were developed and evaluated. Based on the data obtained from this study, both products were stable for 6 months with high labeling efficiency. The prepared cold kit was found sterile and pyrogen free. The bacterial infection and sterile inflammation imaging capacity of (99m)Tc-CEF was evaluated. Based on the in vivo studies, (99m)Tc-CEF has higher uptake in infected and inflamed thigh muscle than healthy thigh muscle.

Radiolabeling and in vitro evaluation of a new 5‐fluorouracil derivative with cell culture studies

“…The radiochemical purity of 99m Tc radiopharmaceutical is highly dependent on the pH. 6 The effect of pH on the radiochemical purity of [ 99m Tc]TcE was examined for pH 5.0 and 7.4. The potassium phosphate monobasic dibasic solution was used to adjust the pH 7.4.…”

“…99m Tc has ideal properties such as 140 keV pure gamma photon emission, 6 h physical half‐life, low cost, readily availability. These make the usage of Tc‐99m in diagnosis even more widespread . The biomolecules of the radiopharmaceuticals are responsible for the accumulation of the radionuclide in the targeted tissue.…”

“…These make the usage of Tc-99m in diagnosis even more widespread. [6][7][8] The biomolecules of the radiopharmaceuticals are responsible for the accumulation of the radionuclide in the targeted tissue. High accumulation in the target and low accumulation in nontarget tissue is preferred to increase the resolution and sensitivity of the images and to reduce radiation damage in the rest of the body.…”

Imaging bacteria with radiolabelled quinolones, cephalosporins and siderophores for imaging infection: a systematic review

“…Ilem-Ozdemir and coll. [88] labelled with 99m Tc the cefotaxime sodium. Then, they evaluated its biodistribution in rats, infected with 4 × 10 10 CFU of E. coli or turpentine oil as control.…”

“…F. Mirshojaei [87]Na-dithionite9.4 × 10 4 92 % at 12 h85 % at 24 hMouseLiver (+), kidneys (++) 99m Tc-cefotaxime sodiumD. Ilem-Ozdemir [88]Stannous tartrate/Stannous chloride3.4 × 10 3 92 % at 24 h85 % at 24 hRatLiver (+), kidneys (++) 99m Tc-ceftriaxoneM. Mostafa [89]Direct labelling—SnCl 2 ·2H 2 O1.90 × 10 2 n.…”