PolyPeptide Synthesis

Protein Introduction

Peptide Custom Synthesis Service Introduction

Peptide custom synthesis service is one of the core services of us Peptide.ltd. We use high-end and professional instruments to ensure that we provide the best quality products and service, for example HPLC detectors,Waters LC-MS etc.

Peptide.ltd R&D team consists of many professional doctors and researchers who have rich professional knowledge and rigorous work attitude. We have establised perfect management system (ISO 9001:2008) and strict production management system. In order to develop and produce the best quality peptide products, Peptide.ltd encourage research and innovation, we have invested a lot of money and technology,achieved excellent results in the field of peptide custom synthesis.

After years of dedicated research and rich experience in peptide production, Peptide.ltd peptide development technology is mature and stable, we can do custom systhesis of various types of peptides to meet the needs of different customers.

Custom Synthesis Services Offer:

1) Linear peptides synthesis: different quantity from “mg” to “Kg”, up to 180 residues

2) Different purity specification: >70%,>80%,>90%,>95%,>98%,>99% and crude,desalted etc, match different customers’ requirements

3) Range of peptide modifications: C-terminal modifications, N-terminal modifications, Fluorescence and Dye Labeling Peptides, Cyclic Peptides Synthesis, Phosphopeptides etc

4) Range of peptides with different structures: Cyclic peptides,MAPs,Linear peptides etc

5) Range of antigen peptides: 0VA coupling,BSA,KLH etc

6) Flexible packaging service: we can do aliquots packing according to customers’ requirements for free

Highlight Specially:

1) Genius quality: the basis for long-term cooperation. COA,HPLC,MS can be provided along with every lot of peptide orders.

2) Fast custom synthesis time: 1-3 weeks

3) Rich experience of custom synthesis skills: Cyclic peptides synthesis,Fluorescence and Dye labeling peptide etc more than 400 kinds of modififcations, up to 180 residues

4) High synthesis success rate: >98%

5) Strict confidentiality system: confidential agreement can be signed

Small Molecules Synthesis Service Introduction

Peptide.ltd has many years rich expreience in the field of small molecule synethesis. Our technology team is mainly consist of Doctors who have rich overseas study experience and chemicals experts, we cooperate with well-known foreign university laboratories to provide high-end technical support for small molecule synthesis service.

At present, Peptide.ltd has an office of 500 square meters and a standard laboratory of 1,200 square meters,equipped with professional imported precision instrucments,fully armed with whole processes from research and development,production and manufacturing,purification,freeze-drying,quality management and quality inspection. For example HPLC,imported lyophlizeer,MS,GC,Ultra pressure liquid chromatography etc instruments,provide customers with comprehensive support.

After continuous efforts,Peptide.ltd has accumulated rich experience in the field of small melecule synthesis. We can provide customers with efficient small molecule synthesis service. Meantime, we have maintainned long-term good cooperative relations with many well-known pharmaceutical factories,university laboratories,research institutes. Our services include research and development,pilot test and batch production of various types of organic intermediates.

What Reactions We Are Good At:

1) Bromination,oxidation-reduction reactions,chiral reactions and separation,condensation etc.

2) Refrigeration(up to 60℃),high-pressure reactions (till 60KGs) etc.

What Compunds We Are Good At:

Fine chemical intermediates and their derivatives,heterocyclic compounds for example Pyrimidine,Thiophene,Pyridine,Iminazole and their derivatives.

What Services We Offer:

1) Custom synthesis service: we offer efficient custom synthesis service of small molecules you want

2) Asymmetric synthesis service: we have the ability to offer asymmetric synthesis

3) Development and scale-up production service: we have rich experience in customized research and development,process optimization and lot commercial production of advanced intermediates,it is no problem to provide custom synthesis and manufacturing service from “gram” to “tons” .

Antibody Production

peptide.ltd provides high-quality and comprehensive custom antibody production services covering every step of monoclonal and polyclonal development.

Range of Services

Highlights

Guaranteed results: We guarantee the positive western blot result and high ELISA titer (> 64,000 for polyclonal antibody and > 128,000 for monoclonal antibody).

Customized protocols: We provide customized antibody production services accroding to the requirments.

Full service: Keep close contact and communication with you during the whole project process, and report the project progress at any time.

Differences Between Monoclonal and Polyclonal Antibodies

Monoclonal Antibodies

Polyclonal Antibodies

Advantages

· High specificity to a single epitope

· Low likelihood of cross-reactions and background noise

· Batch to batch homogeneity

· Easy to produce large quantities of identical antibody

· Higher affinity against the antigen due to recognition of multiple epitopes

· Tolerance to antigen changes

· Easy to produce with an inexpensive price and a short period of time

· Highly stable and tolerant of pH or buffer changes

Disadvantages

· Long period of time of production

· Significantly expensive

· Intolerance to changes in the antigen

· Variability between different batches

· High likelihood of cross-reactions

· Background noise

Applications

· Detection for a specific antigen

· Staining cells with less background

· Detection of the changes in molecular conformation or phosphorylation states

·Immunotherapy

· Detection for a known or unknown isoforms of antigens with high antigen homolog

· Detection for targets with possible genetic glycosylation or conformational changes

· Detection a target in solutions with varying pH and salt concentrations

In summary, monoclonal antibodies are ideal solutions for diagnostic manufacturing and therapeutic drug development that require large volumes of identical antibody against a single epitope. Polyclonal antibodies provide more advantages than that of monoclonal antibodies for general research applications.

Differences Between Species

The most commonly used hosts for antibody production are mice and rabbit, while other hosts are rat, goat and chicken. The characteristics are as follows:

Advantages		Disadvantages
mice	· Can be used to produce Monoclonal Antibodies · Short immunization cycle · Low cost
rabbit	· High success rate · larger range of antigens · Higher affinity and specificity · greater variety of epitopes
rat	· Little antigen required · Good for small amount of polyclonal antibody production · Low cost		·Small amount of serum
goat	· Good for large amount of polyclonal antibody production · Serum can be used directly in initial assays		· Large antigen quantities required · High cost
chicken	· High specificity · Moderate cost · Good alternative for highly conserved mammalian proteins		·Difficult to isolate antibodies

peptide.ltd have rich experience in the expression of recombinant proteins (antibodies, enzymes, membrane proteins, cytokines, etc.) in any species. We can provide protein expression and purification services from small-scale to large-scale.

Recombinant Protein Production system

We offer four systems for protein expression, which are mammalian, bacterial (E.coli), yeast and insect cells. Click on the system you are interested in to see a breakdown of the steps involved with approximate pricing.：

E.coli is the most commonly used protein expression system, for its advantages of fast growing, high protein expression level, and low cost (compared to mammalian expression system).

Mammalian cells can correctly and effectively express eukaryotic proteins, including the synthesis, processing, and secretion of proteins.

Yeast protein expression system is a ideally suitable expression system for both secretion and intracellular expression as the yeast offer relatively easy genetic manipulation and rapid growth to high cell densities on inexpensive media.

The baculovirus expression vector system (BEVS) is one of the four major expression systems of genetic engineering. BEVS has several advantages of using the baculovirus-insect cell expression system.

Comparison between different systems for protein expression

System	Bacterial	Mammalian	Yeast	Insect
Turnaround	4-6 weeks	6-9 weeks	6-9 weeks	6-9 weeks
Price	Low	Moderate	High	High
Expression Level	>50%	>10%	>20%	>30%
Protein folding	Part folding	Part folding	Correct Folding	Correct Folding
Production scale	Large	Moderate	Moderate	Moderate
Phosphorylation	No	Yes	Yes	Yes
Acetylation	No	Yes	Yes	Yes
Amidation	No	Yes	Yes	Yes
Glycosylation	No	Yes	Yes	Yes
γ-carboxylation	No	Yes	Yes	Yes