Msp96 target ground steel bc

After thawing, skimmed milk fractions were centrifuged at 20,000 g for 20 min at + 4°C to remove cell debris and bacteria. Then, each sample was diluted 1:100 with ultrapure water (20 (link)) and mixed (1:1) with a matrix solution composed of sinapinic acid (Bruker Daltonics, Bremen, Germany) saturated in 50% v/v acetonitrile containing 0.1% trifluoroacetic acid (Merck Darmstadt, Germany). An aliquot (0.5 μl) of each sample was spotted in triplicate on an MSP 96 target ground steel BC (Bruker Daltonics), previously overlaid with a thin layer of sinapinic acid saturated in 100% ethanol (Merck), and allowed to dry for 10 min at room temperature. Spectral profiles were acquired using a MALDI-TOF Microflex LRF mass spectrometer (Bruker Daltonics) equipped with the FlexControl (v. 3.4) software (Bruker Daltonics). Spectra were recorded in the positive linear ion mode within the mass range 4,000–20,000 m/z (laser frequency 20 Hz; ion source 1 voltage, 19.53 kV; ion source 2 voltage, 18.12 kV; lens voltage, 8.12 kV). Three independent spectra for each sample (500 shots each at random positions on the same target place, for spectrum) were manually collected, externally calibrated by the Protein Calibration Standard 1(Bruker Daltonics) and subsequently analyzed.

Mass analysis was conducted on a Bruker microflex™ bench-top MALDI-TOF MS (Bruker Daltonics, Bremen, Germany) using dried-droplet method on a micro scout target (MSP96 target ground steel BC, Bruker Daltonics) with α-cyano-4-hydroxycinnamic acid (HCCA, Sigma-Aldrich, Handels GmbH, Vienna, Austria) as matrix. Flex Analysis 2.4 software (Bruker Daltonics, Bremen, Germany) was used for data processing.

100 µL of a 50 µg/mL solution of ^natLu-PSMA I&T in a 1 mL Eppendorf tube was subjected to external irradiation using a ¹³⁷Cs IBL 437L irradiator (CIS US Inc., NY, USA) at a dose rate of about 5 Gy/min for 100 min reaching a dose of 500 Gy. The sample was purified by HPLC (injection volume 50 µL) using HPLC method A and the peaks of the impurity and the main peak due to ^natLu-PSMA I&T were collected and analysed by MALDI-TOF MS.
Mass analysis was conducted on a Bruker microflex® bench-top MALDI-TOF MS (Bruker Daltonics, Bremen, Germany) using dried-droplet method on a micro scout target (MSP96 target ground steel BC, Bruker Daltonics) with α-cyano-4-hydroxycinnamic acid (HCCA, Sigma-Aldrich, Handels GmbH, Vienna, Austria) as matrix. Flex Analysis 2.4 software (Bruker Daltonics, Bremen, Germany) was used for data processing.

Mass spectrometry was conducted on a Bruker microflex bench-top MALDI-TOF MS (Bruker Daltonics, Bremen, Germany). Samples were prepared via dried-droplet on a micro scout target (MSP96 target ground steel BC, Bruker Daltonics) using α-cyano-4-hydroxy-cinnamic acid (HCCA, Sigma-Aldrich, Handels GmbH, Vienna, Austria) as matrix. Recorded data, summation of 800 shots per spot, was processed using Flex Analysis 2.4 software.