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Blood fingerprints are an important subclass of fingerprint evidence when processing a violent crime scene. The commonly used method by the perpetrators to conceal blood stain is rinsed with water or mixed with the blood of livestock or poultry. The aim of the research presented was to overcome the above drawbacks. Herein, NaYF 4 : Yb, Er, Gd fluorescent upconversion nanorods were conjugated with anti-hHb (UCNRs/anti-hHb) through a coupling reaction. We then used the resultant UCNRs/anti-hHb to detect the fingerprints that inked with the blood of human, porcine and chicken. The latent human blood fingerprints showed improved contrast, whereas the blood fingerprints of porcine and chicken did not. The consequence of detection exhibited that UCNRs/anti-hHb offered the ability of specific recognition. To assess the suitability of the UCNRs/anti-hHb for potential operational use, a variety of parameters (e.g., blood concentration, substrate types and aged time) were investigated. The effectiveness of UCNRs/anti-hHb was also assessed in comparison with Acid Yellow 7 (AY7, an effective blood reagent). The results demonstrated that UCNRs/anti-hHb provided high specificity, high sensitivity, good applicability, and low background, enabling practical applications in forensic sciences. [ABSTRACT FROM AUTHOR]

The hollow nanospheres (NSs) composed of lanthanides have become a hot topic owing to their uncommon magnetic and optical properties arising from the 4f electrons. However, only a few novel methods have been developed for effectively integrating small calcium phosphate (CaP) nanoparticles and rare earth oxide drug carriers into an individual hollow mesoporous nanosphere. Herein, we report a facile, reproducible, room-temperature solution method to prepare multifunctional fluorescent hollow mesoporous Gd 2 O 3 :Eu/CaP (designated as HM-Gd 2 O 3 :Eu/CaP) NSs by using polyacrylic acid calcium (PAA-Ca) as a template. The excellent luminescent property and obvious T 1 -enhancement effect as well as the HM structure endow the HM-Gd 2 O 3 :Eu/CaP NSs with the capacity of simultaneous dual-modal fluorescence, magnetic resonance (MR) imaging and drug delivery. The nanocontainer-functionality of the HM-Gd 2 O 3 :Eu/CaP NSs is further validated upon filling with the anti-cancerogenic agent doxorubicin (drug-loading capacity is 749 μg mg −1 ). In addition, the HM-Gd 2 O 3 :Eu/CaP NSs display excellent pH-responsive and sustained drug release property. In vitro cell cytotoxicity tests verify the HM-Gd 2 O 3 :Eu/CaP NSs have good biocompatibility when the concentration ≤25 mg mL −1 . Taken together, the results suggested that the HM-Gd 2 O 3 :Eu/CaP NSs can be applied as fluorescence and MR dual-modal imaging contrast agents and drug delivery vehicles. [ABSTRACT FROM AUTHOR]

In this paper, the NaYF 4 :Yb,Er,Gd fluorescent upconversion nanorods (UCNRs) were successfully employed as a promising fluorescent label for the detection of blood fingerprints with high sensitivity, low background, high efficiency, and low toxicity on a range of substrates including non-infiltrating materials (glass, ceramic tile, aluminium foil, stainless steel sheet, coin and marble), and infiltrating materials (magazine cover and train ticket). To assess the efficiency of this approach, comparisons were performed with Acid Yellow 7 (AY7, an effective blood reagent) on above-mentioned eight substrates. The fingerprints were cut in halves and the halves treated separately with UCNRs and AY7. The results manifested that UCNRs were superior to AY7 on all test substrates. This work shows that UCNRs are a versatile fluorescent label for the detection of blood fingerprints in criminal science for individual identification. [ABSTRACT FROM AUTHOR]

In this paper, we report a facile and reproducible approach to prepare Eu 3+ -doped gadolinium oxide (Gd 2 O 3 ) hollow mesoporous nanoparticles (HMNPs) by using polyacrylic acid sodium salt (PAAS) NPs as templates. The synthesized NPs are well-dispersed with a diameter of 120 nm and a wall thickness around 20 nm, which were utilized as nanoprobes for simultaneous dual-modal fluorescence and magnetic resonance (MR) imaging and drug delivery due to their excellent luminescent property and obvious T 1 -enhancement effect as well as the HM structure. The Eu 3+ -doped Gd 2 O 3 HMNPs possess the loading capacity for doxorubicin (DOX) as high as 310 μg mg −1 and display the pH-responsive drug release property. In vitro cell cytotoxicity tests on cancer cells verify that the DOX loaded Eu 3+ -doped Gd 2 O 3 HMNPs have comparable cytotoxicity with free DOX at the same concentration of DOX, while Eu 3+ -doped Gd 2 O 3 HMNPs alone show no obvious cytotoxicity. In addition, Eu 3+ -doped Gd 2 O 3 HMNPs exhibit excellent capability in dual-modal fluorescence and MR imaging. Taken together, these findings highlight the fascinating features of Eu 3+ -doped Gd 2 O 3 HMNPs as dual-modal imaging contrast agents and drug delivery vehicles. [ABSTRACT FROM AUTHOR]