跳至主要内容

Gold nanoparticle-based colorimetric method for the detection of prostate-specific antigen

Author：Ning Xia, Dehua Deng, Yiru Wang, Chao Fang, and Su-Juan Li   《International Journal of Nanomedicine》

ABSTRACTS

Background

Prostate-specific antigen (PSA), a serine protease, is a biomarker for preoperative diagnosis and screening of prostate cancer and monitoring of its posttreatment.

Methods

In this work, we reported a colorimetric method for clinical detection of PSA using gold nanoparticles (AuNPs) as the reporters. The method is based on ascorbic acid (AA)-induced in situ formation of AuNPs and Cu2+-catalyzed oxidation of AA. Specifically, HAuCl4 can be reduced into AuNPs by AA; Cu2+ ion can catalyze the oxidation of AA by O2 to inhibit the formation of AuNPs. In the presence of the PSA-specific peptide (DAHSSKLQLAPP)-modified gold-coated magnetic microbeads (MMBs; denoted as DAHSSKLQLAPP-MMBs), complexation of Cu2+ by the MMBs through the DAH–Cu2+ interaction depressed the catalyzed oxidation of AA and thus allowed for the formation of red AuNPs. However, once the peptide immobilized on the MMB surface was cleaved by PSA, the DAHSSKLQ segment would be released. The resultant LAPP fragment remaining on the MMB surface could not sequestrate Cu2+ to depress its catalytic activity toward AA oxidation. Consequently, no or less AuNPs were generated.

Results

The linear range for PSA detection was found to be 0~0.8 ng/mL with a detection limit of 0.02 ng/mL. Because of the separation of cleavage step and measurement step, the interference of matrix components in biological samples was avoided.

Conclusion

The high extinction coefficient of AuNPs facilitates the colorimetric analysis of PSA in serum samples. This work is helpful for designing of other protease biosensors by matching specific peptide substrates.
KEY WORDS
 colorimetric assay, gold nanoparticles, prostate-specific antigen, ascorbic acid, Cu2+ ion
SCREENSHOT

RELATED PRODUCTS
Peptides
CHAINING
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5923276/
标签：

评论

发表评论

此博客中的热门博文

Deubiquitinating enzyme USP9X regulates cellular clock function by modulating the ubiquitination and degradation of a core circadian protein BMAL1

Author：Yang Zhang, Chunyan Duan, Jing Yang, Suping Chen,  Qing Liu, Liang Zhou, Zhengyun Huang, Ying Xu, Guoqiang Xu     《Biochemical Journal》 ABSTRACTS Living organisms on the earth maintain a roughly 24 h circadian rhythm, which is regulated by circadian clock genes as well as their protein products. Post-translational modifications of core clock proteins could affect the circadian behavior. Although ubiquitination of core clock proteins was studied extensively, the reverse process, deubiquitination, has only begun to unfold and the role of this regulation on circadian function is not completely understood. Here, we use affinity purification and mass spectrometry analysis to identify probable ubiquitin carboxyl-terminal hydrolase FAF-X (USP9X) as an interacting protein of the core clock protein aryl hydrocarbon receptor nuclear translocator-like protein 1 (ARNTL or BMAL1). Through biochemical experiments, we discover that USP9X reduces BMAL1 ubiquitina...
发表评论
阅读全文

CAS:85466-18-8|Thymopoietin II (32-35)|RKDV

Contact： Liven Qian(钱叶华)-Custom Peptide Mobile: 13761298676（微信） Email：cps037@chinapeptides.net QQ：2880526724 ChinaPeptides Co., Ltd./强耀生物科技有限公司 Name Thymopoietin II (32-35) Code [85466-18-8] The alias Thymopoietin II (32-35) Sequence (single letter abbreviation) RKDV Sequence (three-letter abbreviation) H-Arg-Lys-Asp-Val-OH (trifluoroacetate salt) A basic description TP-4 and TP-3; shortest active thymopoietin II fragments described that exhibit potent immunoregulatory properties in vitro and in vivo. solubility The molecular weight 516.6 Chemical formula C21H40N8O7 The purity 80%，90%，95%，98%，99% Weight 1mg,5mg,10mg,50mg,100mg,1g Storage conditions Store at -20°C. Keep tightly closed. Store in a cool dry place. Number of Residues: 4 1-Letter Code: RKDV 3-Letter Code: Arg-Lys-Asp-Val Molecular weight (Mr): 516.6 g/mol Isoelectric point: 10.1 Net charge at pH 7.0: 1.0 Average hydrophilicity: 1.9 Ratio of hydrophilic residues / total number of residues...
1 条评论
阅读全文

Targeting the leptin receptor: To evaluate therapeutic efficacy and anti-tumor effects of Doxil, in vitro and in vivo in mice bearing C26 colon carcinoma tumor

Author：Shahrzad Amiri Darban, Sara Nikoofal-Sahlabadi,  Nafise Amiri, Nafiseh Kiamanesh, Amin Mehrabian, Bamdad Zendehbad, Zahra Gholizadeh, Mahmoud Reza Jaafari     《Colloids and Surfaces B: Biointerfaces》 ABSTRACTS Leptin is an appetite regulatory hormone that is secreted into the blood circulation by the adipose tissue and it functions via its over expressed receptors (Ob-R) in a wide variety of cancers. In the present study, the function of a leptin-derived peptide (LP16, 91–110 of Leptin) was investigated as a targeting ligand to decorate PEGylated liposomal doxorubicin (PLD, Doxil ? ) surface and the anti-tumor activity and therapeutic efficacy of Doxil in C26 (Colon Carcinoma) tumor model were also evaluated. As a result of this, Doxil with different LP16 peptide density (25, 50, 100 and 200 peptide on the surface of each liposome) was successfully prepared and characterized. In vitro results showed significant enhanced cytotoxicity and cellular b...
发表评论
阅读全文