Pentetic acid 20.8mg kit for radiopharmaceutical preparation

Purpose To synthesize two low-molecular-weight iron chelates and compare their T1 contrast effects with those of a commercial gadolinium-based contrast agent for their applicability in dynamic contrast material–enhanced (DCE) magnetic resonance (MR) imaging. Materials and Methods The animal experiments were approved by the local ethics committee. Two previously described iron (Fe) chelates of pentetic acid (Fe-DTPA) and of trans-cyclohexane diamine tetraacetic acid (Fe-tCDTA) were synthesized with stability constants several orders of magnitude higher than those of gadolinium-based contrast agents. The T1 contrast effects of the two chelates were compared with those of gadopentetate dimeglumine in blood serum phantoms at 1.5 T, 3 T, and 7 T. For in vivo studies, a human breast cancer cell line (MDA-231) was implanted in five mice per group. The dynamic contrast effects of the chelates were compared by performing DCE MR imaging with intravenous application of Fe-DTPA or Fe-tCDTA on day 1 and DCE MR imaging in the same tumors with gadopentetate dimeglumine on day 2. Quantitative DCE maps were generated with software and were compared by means of a one-tailed Pearson correlation test. Results Relaxivities in serum (0.94 T at room temperature) of Fe-tCDTA (r1 = 2.2 mmol−1 · sec−1, r2 = 2.5 mmol−1 · sec−1) and Fe-DTPA (r1 = 0.9 mmol−1 · sec−1, r2 = 0.9 mmol−1 · sec−1) were approximately twofold and fivefold lower, respectively, compared with those of gadopentetate dimeglumine (r1 = 4.1 mmol−1 · sec−1, r2 = 4.8 mmol−1 · sec−1). Used at moderately higher concentrations, however, iron chelates generated similar contrast effects at T1-weighted MR imaging in vitro in serum, in vivo in blood, and for DCE MR imaging of breast cancer xenografts. The volume transfer constant values for Fe-DTPA and Fe-tCDTA in the same tumors correlated well with those observed for gadopentetate dimeglumine (Fe-tCDTA Pearson R, 0.99; P = .0003; Fe-DTPA Pearson R, 0.97; P = .003). Conclusion Iron-based contrast agents are promising as alternatives for contrast enhancement at T1-weighted MR imaging and have the potential to contribute to the safety of MR imaging. Online supplemental material is available for this article.

Abstract licence: CC BY

Background and Aims: For endodontic therapy to be successful, the smear layer produced by the root canal instruments must be removed. The study's objective is to evaluate the effectiveness of radicular dentin microhardness modification and smear layer removal utilizing various chelating agents. Materials and Methods: Extracted human mandibular single-rooted premolar teeth were selected for the study. The specimens were sectioned to obtain a standard root length and, working length determination was done. Cleaning and shaping were done in all the samples till the size F3 (Protaper universal). Based on the chelating agents using samples were randomly divided into four groups, Group-I: Saline (negative control), Group-II: 17% EDTA (DeSmear, Ahmedabad, Gujarat) (positive control), Group-III: 0.2% Chitosan (Everest-Biotech, Bengaluru), Group-IV: 20% N-Acetyl cysteine (NAC) (Sisco Research Laboratories, Mumbai), Group-V: 5% Pentetic acid (New Alliance Fine chem Pvt Ltd, Mumbai). All the samples were prepared for smear layer removal and surface roughness evaluation using an atomic force microscope. Results: = 0.000) the mean roughness average was higher among group II EDTA (148 ± 8.5) followed by group III 0.2% Chitosan (92.5 ± 3.42), group IV 20% NAC (85.2 ± 2.17), and group V 5% Pentetic acid (73.3 ± 3.39) and least by group I Saline (59.3 ± 3.31). The highest smear layer removal was seen with group II (EDTA) followed by group III (0.2% Chitosan), group IV (20% NAC), and group V (Pentetic acid). Conclusion: All the chelating agents removed smear layer in coronal third, middle third whereas none of them were able to entirely eliminate from the apical third. Chitosan with smear layer removal capacity equal to EDTA with limited roughness can be considered as a valid alternative as final irrigant.

Abstract licence: CC BY-NC-SA

While bipolar disorder patients can benefit from lithium therapy, high levels of lithium in the serum can induce undesirable systemic side effects. Intranasal (IN) lithium delivery offers a potential solution to this challenge given its potential to facilitate improved lithium transport to brain when delivered to the olfactory mucosa. Herein, a sprayable, in situ forming nanoparticle network hydrogel (NNH) based on Schiff base interactions between chelator-functionalized oxidized starch nanoparticles (SNPs) and carboxymethyl chitosan (CMCh) is reported that can be deployed within the nasal cavity to release ultra-small penetrative SNPs over time. Chelating functional groups including citrate, ethylenediaminetetraacetic acid, and pentetic acid are shown to bind a variety of cations including lithium, magnesium, and calcium, with chelation directly linked to enhancements in the gel mechanics even for monovalent lithium. The hydrogels show high in vitro cytocompatibility with mouse striatal neuron and human primary nasal cell lines. Effective IN delivery of lithium to the brain is demonstrated for the first time, with both solution-based and hydrogel-loaded lithium showing in vivo efficacy in an amphetamine-induced pre-clinical rat bipolar manic phase model; specifically, IN-delivered NNHs can maintain successful attenuation of locomotor activity for up to 6 h while all other tested treatments (drug-only IN or conventional intraperitoneal delivery) failed to retain attenuation for more than two hours at the same lithium dose. As such, in situ-gelling and ion-chelating NNHs represent a new material that can effectively enable metal ion management in biomedical applications.

Abstract licence: CC BY-NC

In this work, nanocomplexes based on chitosan grafted by carboxy-modified polylactic acid (SPLA) were prepared with the aim of loading simultaneously two anticancer drugs – doxorubicin and 5-fluorouracil, as well as to control their release, reduce the initial burst and boost cytotoxicity. The SPLA was prepared by a polycondensation reaction, using pentetic acid as the core molecule, and linked to the chitosan backbone through a coupling reaction. Nanocomplexes loaded with both drugs were formulated by the polyelectrolyte complexation method. The structure of the SPLA was characterized by 1H NMR, while the product CS-SPLA was analyzed by FTIR-ATR to prove the occurrence of the reaction. Results showed that the diameters and ζ-potential of the nanocomplexes fall in the range 120–200 nm and 20–37 mV, respectively. SEM and TEM analysis confirmed the spherical shape and dimensions of the nanocomplexes. The presence of hydrophobic side chain SPLA did not influence the encapsulation efficiency of the drugs but strongly reduced the initial burst and prolonged release over time compared to unmodified chitosan. MS analysis showed that no degradation or interactions between the drugs and carrier were exhibited after loading or 24 h of release had taken place, confirming the protective role of the nanocomplexes. In vitro tests demonstrated an increase in the cytotoxicity of the drugs when loaded in the prepared carriers.

Abstract licence: CC BY-NC-ND