Analytical Sciences : the international journal of the Japan Society for Analytical Chemistry This is an RSS file. You can use it to subscribe to this data in your favourite RSS reader or to display this data on your own website or blog.

Tag-free protein modification by lipoate ligase A: exploring substrate tolerance
This study delves into the functional intricacies of lipoate ligase A (LplA), an enzyme showing great promise in bioconjugation due to its unique capacity for introducing azido groups into proteins without requiring a genetic tag. We aimed to enhance the understanding of LplA's functionality, particularly its substrate tolerance and the reliability of various analytical techniques. A pivotal aspect of our approach was incorporating azido groups into a range of proteins, followed by the addition of the fluorescent molecule Cy3 via click chemistry. Analysis of fluorescent intensity in the altered proteins indicated varying d...
Source: Analytical Sciences : the international journal of the Japan Society for Analytical Chemistry - March 20, 2024 Category: Chemistry Authors: Shunsuke Yamazaki Kazutoshi Takahashi Yutaka Matsuda Source Type: research

LC-MS/MS analysis of components in smoke from e-cigarettes that use guarana extract as the caffeine source
In this study, an LC-MS/MS analysis of components in the smoke from e-cigarettes with GE was performed. The concentration ranges of Caf and the minor components theophylline (TP), theobromine (TB), and paraxanthine (PX) in e-liquid and cigarette smoke extract (CSE) of five e-cigarette products were determined. The concentration ranges of e-liquid and CSE were 2.17-8.62 mg/mL and 0.17-1.17 µg/puff for Caf, 0.09-37.58 µg/mL and 0.03-11.88 ng/puff for TB, 50.28-185.26 ng/mL and 0.00-0.05 ng/puff for TP, and 0.44-4.09 µg/mL and 0.03-0.20 ng/puff for PX, respectively. By comparing the peak area ratios of e-liquid and CSE, we...
Source: Analytical Sciences : the international journal of the Japan Society for Analytical Chemistry - March 20, 2024 Category: Chemistry Authors: Suzuna Saruwatari Makoto Takada Junpei Mutoh Naoya Kishikawa Naotaka Kuroda Mitsuhiro Wada Source Type: research

Itemized determination of As, Sb, Bi, Se, and Ge in graphite sample by HG-AFS with high-temperature microwave digestion
Anal Sci. 2024 Mar 14. doi: 10.1007/s44211-024-00526-6. Online ahead of print.ABSTRACTIn this paper, we optimized a method for fast and accurate determination of five impurity elements (As, Sb, Bi, Se, and Ge) in graphite samples to overcome the shortcomings of existing methods, such as complicated equipment, cumbersome process, multiple-time preparation, separate determination, and large error in results. Graphite samples were digested with HNO3-H2SO4-HClO4-HF in a high-temperature and high-pressure microwave digestion apparatus, and the elements were extracted and determined separately by AFS (atomic fluorescence spectro...
Source: Analytical Sciences : the international journal of the Japan Society for Analytical Chemistry - March 14, 2024 Category: Chemistry Authors: Jian-Wei Meng Li-Ping Wang Ai-Qin Liu Yan-Qiao Hu Li Wei Chao Chen Xue-Mei Zhang Liang-Cheng Zhao Hua-Jie Liu Meng-Hua Sun Source Type: research

LC-MS/MS determination of pyocyanin-N-acetyl cysteine adduct: application for understanding Pseudomonas aeruginosa virulence factor neutralization
This study investigates the neutralization reaction between PCN and N-acetyl cysteine (NAC) for bacterial inhibition and explores its mechanism of action. The neutralization adduct (PCN-NAC) was synthesized by reacting the purified PCN and NAC. The adduct was analyzed and its structure was elucidated. LC-MS/MS method was developed for the determination of PCN-NAC in P. aeruginosa cultures post-treatment with NAC (0-5 mg/mL). The corresponding anti-bacterial potential was estimated and compared to nanoparticles (NPs) alone and under stress conditions. In silico studies were performed to support explaining the mechanism of a...
Source: Analytical Sciences : the international journal of the Japan Society for Analytical Chemistry - March 13, 2024 Category: Chemistry Authors: Faten Farouk Rania Ibrahim Shebl Source Type: research

Pimonidazole-alkyne conjugate for sensitive detection of hypoxia by Cu-catalyzed click reaction
Anal Sci. 2024 Mar 13. doi: 10.1007/s44211-024-00520-y. Online ahead of print.ABSTRACTHypoxia is involved in various diseases, such as cancers. Pimonidazole has often been used as the gold-standard marker to visualize hypoxic regions. Pimonidazole labels hypoxic regions by forming a covalent bond with a neighboring protein under hypoxic conditions in the body, which is detected by immunohistochemistry performed on tissue sections. To date, some pimonidazole-fluorophore conjugates have been reported as fluorescent probes for hypoxia imaging that do not require immunostaining. They are superior to pimonidazole because immuno...
Source: Analytical Sciences : the international journal of the Japan Society for Analytical Chemistry - March 13, 2024 Category: Chemistry Authors: Iori Tamura Daichi M Sakamoto Bo Yi Yutaro Saito Naoki Yamada Yoichi Takakusagi Shinsuke Sando Source Type: research

Correction for the calculated XANES spectra of 1,4,7,10-alkyltetracenes considering the total electron yield (TEY) efficiency of sp < sup > 2 < /sup > - and sp < sup > 3 < /sup > -carbon atoms
Anal Sci. 2024 Mar 11. doi: 10.1007/s44211-024-00532-8. Online ahead of print.ABSTRACTThe calculated X-ray-absorption-near-edge-structure (XANES) spectra in the CK region of 1,4,7,10-alkyltetracenes, which are composed of both sp2-C atoms in the tetracene ring and sp3-C atoms in the alkyl-chains, can be corrected by considering the total electron yield (TEY) efficiency of sp3-C relative to sp2-C. In the correction, the previously measured TEY efficiency of k = 0.51 is applied to the calculated transition probabilities for sp3-C atoms. Then the calculated CK-XANES obtained from density functional theory (DFT) calculations c...
Source: Analytical Sciences : the international journal of the Japan Society for Analytical Chemistry - March 12, 2024 Category: Chemistry Authors: Yasuji Muramatsu Source Type: research

Micro/nanofluidic device for tamsulosin therapeutic drug monitoring in patients with benign prostatic hyperplasia at point of care
Anal Sci. 2024 Mar 11. doi: 10.1007/s44211-024-00533-7. Online ahead of print.ABSTRACTDiscovering the balance between toxicity and efficacy for many drugs requires therapeutic drug monitoring (TDM) of their concentrations in the blood. Here, a hot-embossed microfluidic device with a new design integrated to a nanofracture is presented for purification of blood samples from numerous proteins and cells, allowing to the separation of small molecules from blood matrix. The device was used to separate and quantitatively detect tamsulosin drug after derivatization with fluorescamine reagent, allowing converting it from a neutral...
Source: Analytical Sciences : the international journal of the Japan Society for Analytical Chemistry - March 12, 2024 Category: Chemistry Authors: Zaidon T Al-Aqbi Hassan T Abdulsahib Faris A J Al-Doghachi Source Type: research