All NMR spectra were acquired by Varian 400 or Varian Gemini 200 Spectrometers using standard NMR tubes at 298 K, and operating at 400 or 200 MHz for 1H and at 100 or 50 MHz for 13C. Residual protic solvent CHCl3 (δH = 7.26) was used as the internal reference, and 13C NMR spectra were recorded using the central resonance of CDCl3 (δC = 77.0) as the internal reference. Spectrophotometry was performed by a Fourier-Transform InfraRed (FTIR) spectrometer Perkin-Elmer UATR-2 system. Mass spectrum was recorded on an Agilent 5,988 gas-chromatograph with a mass-selective detector MSD HP 5,790 MS, utilizing electron ionization (EI) at an ionizing energy of 70 eV. A fused silica column (30 m × 0.25 mm HP-5; cross-linked 5% PhMe siloxane, 0.10 μm film thickness) was used with helium carrier flow of 30 ml/min. The temperature of the column was varied, after a delay of 3 min from the injection, from 65 to 300°C with a slope of 15°C min−1.
Gemini 200 spectrometer
Manufactured by Agilent Technologies
Sourced in United States
The Gemini-200 spectrometer is a laboratory instrument designed for spectroscopic analysis. It is capable of measuring the absorption or emission spectra of various samples across a range of wavelengths. The core function of the Gemini-200 is to provide accurate and reliable spectroscopic data for research and analytical purposes.
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Lab products found in correlation
Ea 1110 chns o, by Carlo Erba (2 mentions)
Unity 400 spectrometer, by Agilent Technologies (2 mentions)
Avance 500, by Agilent Technologies (1 mentions)
Ft ir 1725x spectrophotometer, by PerkinElmer (1 mentions)
Zetapals, by Brookhaven Instruments (1 mentions)
Silica gel, by Merck Group (1 mentions)
Uv 1601 spectrophotometer, by Shimadzu (1 mentions)
Dsc 60, by Shimadzu (1 mentions)
Model 343 polarimeter, by PerkinElmer (1 mentions)
System 2000 ft ir spectrophotometer, by PerkinElmer (1 mentions)
Spectrum one ftir spectrometer, by PerkinElmer (1 mentions)
5973 mass spectrometer, by Agilent Technologies (1 mentions)
2400 analyzer, by PerkinElmer (1 mentions)
B 540, by Büchi (1 mentions)
Inova 400, by Agilent Technologies (1 mentions)
Mercury plus 400, by Agilent Technologies (1 mentions)
Dip 370 polarimeter, by Jasco (1 mentions)
0.2 mm precoated silica gel aluminium sheets, by Merck Group (1 mentions)
Ltq orbitrap xl mass spectrometer, by Thermo Fisher Scientific (1 mentions)
Discovery c18 column, by Merck Group (1 mentions)
17 protocols using gemini 200 spectrometer
1
Characterization of Organic Compounds
2
Synthesis and Characterization of Steroid Derivatives
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All synthetic reagents were analytically pure and solvents were prepared according to the standard procedures before being used. The starting steroid derivatives were purchased from Galenika AD (Belgrade, Serbia) and were recrystallized from a suitable solvent. Flash column chromatography (FCC) was carried out with Merck silica gel 0.040-0.063 mm. Thin layer chromatography (TLC) was carried out on precoated silica gel 60 F 254 plates. Melting points were determined on a Digital melting point WRS-1B apparatus and are uncorrected. IR spectra were recorded with Perkin-Elmer FT-IR 1725X spectrophotometer. 1 H and 13 C NMR spectra were recorded in DMSO-d 6 and/or CDCl 3 with Bruker Avance 500 ( 1 H at 500 MHz, 13 C at 125 MHz) and Varian Gemini-200 spectrometers ( 1 H at 200 MHz, 13 C at 50 MHz) and TMS was used as an internal reference. Chemical shifts (δ) are measured in ppm and coupling constants (J) in Hz. The homonuclear 2D (NOESY, COSY) and the heteronuclear 2D 1 H- 13 C spectra (HSQC, HMBC) were recorded with the usual settings. The high-resolution mass spectra (HRMS) were taken with Agilent 6210 TOF LC/MS or Thermo Scientific HESI-LTQ Orbitrap XL spectrometers. Elemental analyses were performed on Vario EL III.
3
Characterization of FA-MNP/CDDP/TFPI-2 Complexes
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To determine the loaded amount of CDDP, the FA-MNP/CDDP/TFPI-2 complexes were dissolved in 6 mL of 12-oxophytodienoic acid (OPDA)/DMF (1.2 mg/mL) and measured at 1 nm by ultraviolet (UV) spectrophotometry30 (link) (Encapsulation rate%= CDDP content /CDDP integral dose×100%). The benzene ring structure of the FA molecule has characteristic absorption peaks at 256 nm, 283 nm, and 365 nm. With these features, we adopted UV spectrophotometry (UVIKON923 BIO-TEK, USA) to analyze the content of FA in the complexes 31 (link). The 1H NMR spectrum of FA-MPEG-PEI was obtained on a Gemini-200 spectrometer (Varian, CA, USA) using D2O as the solvent to detect the chemical bonds of FA-MPEG-PEI.
Morphological examination of the complexes was performed using a JEM-2010HR high-resolution transmission electron microscopy (TEM) after counterstaining with uranyl acetate. For the resulting complexes, their particle sizes and zeta potentials were determined with a zeta potential analyzer (ZetaPALS, Brookhaven Instruments Corporation, USA).
Morphological examination of the complexes was performed using a JEM-2010HR high-resolution transmission electron microscopy (TEM) after counterstaining with uranyl acetate. For the resulting complexes, their particle sizes and zeta potentials were determined with a zeta potential analyzer (ZetaPALS, Brookhaven Instruments Corporation, USA).
4
Characterization of Organic Compounds
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Infrared (IR) spectra were recorded on a Bruker ALPHA fourier transform (FT)-IR apparatus (Billerica, MA, USA) equipped with a platinum attenuated total reflection module. The nuclear magnetic resonance spectra were recorded in DMSO-d6 solution in 5 mm tubes at 30°C on a Varian Gemini 200 spectrometer (199.98 MHz for 1H, 50.29 MHz for 13C). The center of the solvent multiplet (DMSO-d6) was used as internal standard (chemical shifts in δ ppm), which was related to TMS with δ 2.49 ppm (1H) and 39.5 ppm (13C).
5
Organic Synthesis Protocol Characterization
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Chemicals, solvents, and reagents used for the syntheses were purchased from Sigma-Aldrich (St. Louis, MO), Fluka (Newport News, VA), or Alfa Aesar (Ward Hill, MA), and were used without any further purification. Column chromatography (CC): silica gel (Merck, Darmstadt, Germany). Mps: Büchi apparatus (Büchi, Flawil, Switzerland), uncorrected. 1H NMR and 13C NMR spectra: Varian Gemini-200 spectrometer (Varian Medical Systems (VAR), Palo Alto, CA); CDCl3; δ in ppm rel. to Me4Si as an internal standard; J in Hz. Elemental analyses were performed on a Carlo Erba EA-1110 CHNS-O instrument in the Microanalysis Laboratory of the Department of Pharmacy of Genoa University.
6
Synthesis and Characterization of P407-Folic Acid Conjugate
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P407-FA was synthesized via a previously reported method with modifications [28 (link)]. Firstly, 87.58 mg (0.20 mmol) of FA was dissolved in 5 ml dried DMSO and added to a one-neck flask. Then, 35.32 mg (0.22 mmol) of CDI was added to the solution, and the reaction was stirred for 24 h at room temperature in the dark, then we added 0.62 g (0.05 mmol) of P407 which had been previously dried overnight in a vacuum and the reaction was allowed to proceed in the dark for 1 day at room temperature. After the reaction was completed, the mixture was dialyzed for 5 d in a dialysis bag with a molecular cut off of 3000 to remove free FA. P407-FA was recovered via lyophilization. The resulting product was dried in a vacuum oven for 2 d and stored in a dry box, yielding 56% w/w of product.
Prepared P407-FA was characterized by 1H-NMR and differential scanning calorimetry (DSC-60; Shimadzu Corporation, Kyoto, Japan). 1H-NMR spectrum of P407-FA was recorded on a Gemini-200 spectrometer (Varian, CA, USA) using DMSO-d6 as the solvent. UV-Vis spectra were acquired using a UV-1601 spectrophotometer (Shimadzu Corp., Kyoto, Japan) to determine the degree of conjugation of FA by measuring the absorbance at 360 nm.
Prepared P407-FA was characterized by 1H-NMR and differential scanning calorimetry (DSC-60; Shimadzu Corporation, Kyoto, Japan). 1H-NMR spectrum of P407-FA was recorded on a Gemini-200 spectrometer (Varian, CA, USA) using DMSO-d6 as the solvent. UV-Vis spectra were acquired using a UV-1601 spectrophotometer (Shimadzu Corp., Kyoto, Japan) to determine the degree of conjugation of FA by measuring the absorbance at 360 nm.
7
Characterization of 2-Phenylindolyl Compounds
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A Reichert Köfler hot-stage apparatus was used to determine the melting points, that are uncorrected. For routine nuclear magnetic resonance spectra, compounds were dissolved in DMSO-d6 and a Varian Gemini 200 spectrometer operating at 200 MHz was utilized. Analytical TLC was carried out on Merck 0.2 mm precoated silica gel aluminum sheets (60 F-254). Optical rotatory powers ([α]D) were determined using a Perkin Elmer model 343 polarimeter, at a temperature of 22°C. The ≥95% purity of tested compounds was confirmed by combustion analysis. 2-Phenylindol-3-ylglyoxylyl chloride 6 was prepared according with reported procedures17 (link)18 (link).
8
Spectroscopic Analysis of Organic Compounds
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Ultraviolet–visible (UV–Vis) electronic absorption spectra were obtained using a Shimadzu UV–Vis Multispec-1500 spectrophotometer (Japan), and steady-state fluorescence was performed using a FLS920 Edinburgh Instruments Spectrophotometer (England). The 1H and 13C NMR spectra were recorded with the use of a Varian Gemini 200 spectrometer operating at 200 MHz. Dimethylsulfoxide (DMSO-d6) was used as a solvent and tetramethylsilane as internal standard.
The elemental analysis was made with a Vario MACRO 11.45-0000, Elementar Analyser System GmbH (Germany), operating with the software VARIOEL 5.14.4.22.
The elemental analysis was made with a Vario MACRO 11.45-0000, Elementar Analyser System GmbH (Germany), operating with the software VARIOEL 5.14.4.22.
9
General Analytical Techniques for Researchers
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Example 1
General. TLC: precoated (0.2 mm) silica gel 60 F254 plates from EM Laboratories, Inc.; detection by UV light (254 nm). M.p.: Electrothermal IA9100 digital melting-point apparatus; uncorrected. 1H and 13C NMR spectra: Varian-Unity-400 spectrometer at 400 and 100 MHz or Varian-Gemini-200 spectrometer at 200 and 50 MHz, chemical shifts 8 in ppm with SiMe4 as an internal standard (=0 ppm), coupling constants J in Hz. Elemental analyses were carried out on a Heraeus CHN—O-Rapid elemental analyzer, and results were within ±0.4% of calculated values.
10
Synthesis of PLGA-PEG-OMe Copolymer
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The synthesis methods of PLGA-PEG-OMe (PP) copolymer were as described previously [20 (link)]. Briefly, the 300 mg (0.025 mmol) of PLGA (50/50) with terminal carboxylic acid was activated with 8 mg (0.039 mmol) of DCC in 3 mL of anhydrous dimethylformamide (DMF) under a nitrogen atmosphere for 4 h (a PLGA: DCC mole ratio of 1:1.5). In another flask, 100 mg (~0.029 mmol) of NH2-PEG-OMe was dissolved in 2 mL of anhydrous DMF with 0.1 mL of triethylamine (TEA) for 4 h and then was added to the DCC-activated carboxylic acid end group of PLGA solution in a dropwise manner (PLGA: NH2-PEG-OMe mole ratio of 1:1.2). The reaction mixture was still stirred under a nitrogen atmosphere for overnight. The solution was dialyzed (molecular weight cut-off; MWCO 1000 Da) against distilled water for 12 h to remove the unreacted NH2-PEG-OMe, and then freeze-dry. The PP copolymer product was identified by infrared (IR) and NMR spectroscopy. Infrared spectra (IR) were obtained using a Perkin-Elmer System 2000 FT-IR spectrophotometer (Waltham, MA, USA). 1H-NMR spectra were recorded on a Varian Gemini-200 spectrometer (Palo Alto, CA, USA) using TMS as an internal standard. The chemical shifts are given in δ (ppm), and the coupling constants are given in Hz.
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