This study of the saliva peptid uses a lollipop like ultra filtration probe followed by direct nano lc LT Q mass spectrometry analysis. First, assemble the LLUF probe using a polyether cell phone membrane and an ethylene propylene tube. Next, collect saliva specimens from volunteers and process through the LLUF probe to sample the saliva.
Then proceed directly to nano L-C-L-T-Q mass spectrometry and analyze the data from saliva samples with and without LLUF probe treatment. Ultimately, the saliva peptid can be obtained by analyzing the L-C-M-S-S data and comparing the identified peptides between the two samples. This approach of using a lollipop like ultra filtration probe coupled to a direct nano lc LTQ mass spectrometry analysis offers key advantages over other methods such as digesting saliva proteins into peptides.
Followed by mass spec analysis, The LUF PRO simplifies and cleans the saliva and also enhance the MS dictation of peptides in the whole saliva for clinical application. Using epoxy glue seal the polyether cell phone membranes onto the borders of the triangle polypropylene paddles. Then attach a Teflon fluorinated ethylene propylene tube to a cylinder exit of a triangle.
Polypropylene paddle sterilize the probes with 70%alcohol overnight to evaluate proper seal, immerse the LLUF probes in 50 milligrams per milliliter. Blue dextran solution for two hours. Confirm the absence of blue dextran in the collected samples.
Recruit healthy 20 to 40-year-old volunteers. After an oral rinse with water, ask the subject to spit whole saliva samples onto an ice cooled vessel. Pool all samples and store on ice.
Immediately after the collection, proceed to a four degree Celsius room with 200 microliter saliva for the sampling with LLUF probes. Now soak the polyether cell phone membrane into human saliva in a culture dish. Create negative pressure by withdrawing a syringe to simulate an ultra filtration process for sampling from the saliva.
Next, determine the protein concentrations Prepare one microgram per microliter of the saliva protein samples for nano lc mass spectrometry analysis. For sample analysis, we use an exigent nano lc online coupled with a Finnegan LTQ mass spectrometer. First load five microliters of the undigested saliva samples to the trap column of the nano lc system by the auto sampler.
After a wash step, switch the valve and deliver a zero to 50%linear gradient of buffer B to the trap and the C 18 separation column. Using the data dependent mode of Excalibur, collect ms ms spectra of the four strongest MS ions above an intensity of one times 10 to the fourth. For each sample, perform duplicate runs of three different separate preparations.
Then import the data file into sequester sorcerer two system select to search against an appropriate human NCBI protein database using non enzyme specificity. After sequester searching, the results automatically filter, validate and display in peptide profit and protein profit based on sequester results. Peptide profit estimates a comprehensive probability P score that a peptides assignment is correct versus incorrect, and also identifies additional information on each peptide sequence.
Protein profit computes a probability score from zero to one for each protein on the basis of peptides assigned to Ms.Ms Spectra. This section determines a capability of LLUF probes to remove the oral bacteria for bacterial detection culture, the saliva samples before and after LLUF probe collection on auger plates for a test of aerobic bacteria. Use antibiotic-free LB auger plates at 37 degrees Celsius for one day and for anaerobic bacteria, use gas pack to culture.
The sample on bru broth, auger plates under anaerobic conditions at 37 degrees Celsius for one day. The fabrication of lollipop, like ultra filtration devices facilitate sampling of saliva in an imitated oral environment. In this system, a negatively charged polyether cell phone membrane with a molecular weight cutoff at 30 kilodaltons is glued to a polypropylene paddle and positioned in front of the LLUF probe to filter out larger proteins in saliva.
In order to mimic the human oral environment, a sponge is soaked in saliva using a syringe. The saliva is filtered and collected via the connected tube. Comparing lc chromatograms of saliva before and after LLUF sampling led to the identification of indigenous saliva peptids by nano L-C-L-T-Q mass spectrometry.
Since these differential chromatograms are derived without chemical or enzymatic digestion, they simplify sample preparation for clinical purposes. In this sample. After LLUF elucidation of the different protein compositions identified 131 peptides in undigested saliva.
These peptides are fragments derived from various proline-rich proteins. Actin alpha amylase alpha one globin beta globin, his sustain one keratin, one mucin seven polymeric immunoglobin receptor serin and S 100. A 9 26 Unique peptides identified in saliva after filtering with LLUF probes are fragments mainly derived from various proline-rich proteins.
This peptide derived from alpha amylase was exclusively detected in a saliva sample without collection with LLUF probes illustrating the capacity of LLUF probes in removing large proteins. Most intriguingly after removing larger proteins, several sequence peptides were detectable in the LLUF probe sampled saliva, notably peptides with proline rich c termini were identified in samples after ultra filtration LLUF probes. You should now have a good understanding of you how to use A-L-L-L-L-U-F PRO to simple saliva for the mass.
Better analysis is very important to collect and simple saliva under consistent conditions. Once master, I believe this technique can be performed properly within the three hours. This approach of for lollipop like ultra filtration probe coupled with direct nano L-C-L-T-Q-M-S, spectrum chain analysis facilitates clinical applications for biomarkers in the diagnosis of human disease.