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Original article
12 (
8
); 4398-4406
doi:
10.1016/j.arabjc.2016.06.015

A novel photonic sensor for the detection of chloramphenicol

, , , ,
 Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Medical University, 300070 Tianjin, China

⁎Corresponding author. Fax: +86 2283336618. huangguowei@tmu.edu.cn (Guowei Huang)

Received: , Accepted: ,
© The Author(s) 2016
Disclaimer:
This article was originally published by Elsevier and was migrated to Scientific Scholar after the change of Publisher.

Peer review under responsibility of King Saud University.

Abstract

A novel photonic sensor using a self-cross-linked imprinting close-packed opal (CPO) as a recognition element was developed for the detection of chloramphenicol (CAP). The self-cross-linked imprinting CPO film was consisted of monodisperse molecular imprinted – N-hydroxymethylacrylamide particles (MI-HAM particles) with self-assembling and self-crosslinking properties. A dilute dispersion of these particles was self-assembled to formation of the highly ordered CPO structure, and at the same time the neighboring particles reacted to form covalent bond to stabilize the CPO structure at the air/dispersion. Thus the obtained self-cross-linked imprinting CPO was characterized by a highly stable three-dimensional (3D) CPO structure without the interference of bulk hydrogel matrix, in which numerous CAP recognition sites were dispersed through the molecular imprinted process. The inherent high affinity of the recognition sites allowed the self-cross-linked imprinting CPO to recognize CAP with high specificity, and changes of the periodic structure enabled the self-cross-linked imprinting CPO to transfer the recognition events into readable optical signals. Then the self-cross-linked imprinting CPO film was packed into a reaction cell with an optical spectrometer to establish a novel photonic sensor. A linear relationship was found between the diffraction intensity decrease and CAP concentration in the range from 2 ng mL−1 to 512 ng mL−1, whereas there was no obvious optical change for CAP analogues, thus indicating that the sensor had selective and sensitive response to CAP molecules. Furthermore, the sensor was applied successfully to detect CAP in drinking water samples. As a result, the developed sensor might offer a potential alternative in routine supervision for residue due to its convenience, low cost, reusability, and high sensitivity as well as selectivity.

Keywords

Photonic sensor
Molecular imprinting technique
Self-cross linking
Close-packed opal
N-hydroxymethylacrylamide
Chloramphenicol
1

1 Introduction

Chloramphenicol (CAP) is a broad-spectrum antibiotic which was widely used in both human and poultry medicine (X.M. Yang et al., 2015; R.R. Yang et al., 2015). However, it has serious side-effects on human beings, such as bone marrow suppression, “gray baby syndrome”, aplastic anemia acute leukemia and so on (Que et al., 2014; X.M. Yang et al., 2015; R.R. Yang et al., 2015). Thus, many countries including USA, Canada and China have controlled CAP contamination in foods and the environment (Wu et al., 2015). There have been traditional analytical techniques used for the determination of CAP content involving immunoassay, high-performance liquid chromatography, gas chromatography-mass spectrometry and electrochemical technique (Yang et al., 2012; Yan et al., 2012; Impens et al., 2003; Shen and Jiang, 2005; Kor and Zarei, 2014). However, these approaches generally need sophisticated equipment and a large number of separate analytical procedures, resulting in more-complex, time consuming and laborious screening procedures (Hassan et al., 2013; Sai et al., 2010). Recently, Alibolandi et al. developed an aptasensor for CAP based on energy transfer of CdTe quantum dots to graphene oxide sheet (Alibolandi et al., 2015). Miao’s research group utilized the DIL-encapsulated liposome as nanotracer to develop a fluorescent aptasensor for sensing CAP (Miao et al., 2016). Ebarvia et al. explored a biomimetic piezoelectric quartz crystal sensor for the detection of CAP (Ebarvia et al., 2015). Yang and the co-workers constructed an immune-sensor based on competitive SERS immunoassay and magnetic separation to monitor CAP (Yang et al., 2016). Although these assays showed great sensitivity and selectivity for CAP, they also required complicated fabrication procedures and expensive sophisticated technical instruments. Therefore, it is still useful and highly desirable to develop a new, facile analytical method to efficiently and rapidly detect CAP levels.

Due to its unique sensing properties and promising applications, diverse photonic sensors have been developed making use of different photonic crystal (PC) materials (Wang et al., 2014; Olyaee et al., 2014; Cullen et al., 2011; Chakravarty et al., 2013). In present work, the close-packed opal (CPO) is a class of three-dimensional (3D) colloidal arrays with a continuously CPO ordered periodic structure and the face centered cubic (FCC) lattice, which displays a distinct optical property based on the Bragg diffraction effect. The CPO structure is different from the non-closest-packed polymerized colloidal crystal array (PCCA) consisted of highly charged monodisperse polymer spheres (Luo et al., 2010; Ward Muscatello et al., 2009; Zeng et al., 2002), and the inverse opal PC (IOPC) composed of periodically ordered interconnecting porosity-endowed hydrogels (Bohn et al., 2010; Zhou et al., 2012). Some works have been reported about the introduction of stimuli-responsive units or molecular recognition elements into the CPO structures to develop chemical sensors. For instance, through the incorporation of natural receptors (ternary complexes and boronic acid), Zhang et al. and Hong et al. fabricated CPO sensors for ciprofloxacin and glucose respectively (Zhang et al., 2014; Hong et al., 2014). Based on the introduction of acetylcholinesterase, Hirsch and co-workers developed a sensing scheme for the determination of acetylcholine and acetylcholinesterase inhibitors, which responded to acetylcholine in the 1–10 nmol L−1 concentration range (Fenzl et al., 2015). However, the deficiency of using the natural recognition units was obvious since it was usually difficult to the finding such a mature natural recognition unit for matching every target molecules (Y. Liu et al., 2009; N. Liu et al., 2009). In addition, the utility of the natural receptors always suffered from a low selectivity. For example, boronic acid could recognize not only glucose but also other sugars, such as mannose, fructose, and galactose (Hu et al., 2007). To avoid the drawbacks, the novel recognition mechanism, i.e., molecular imprinting polymers, should be introduced into the PC structure. Molecular imprinting polymers are synthetic materials with artificially specific recognition sites complementary in size, shape and functional groups to the template molecules, involving an interaction mechanism based on molecular recognition (Valero-Navarro et al., 2011; González et al., 2009; Fang et al., 2009; Luo et al., 2014; Tiwari and Prasad, 2015). Using this approach, Li’s group developed some remarkable chemical sensors by the combination of the molecular imprinting polymers and the IOPC for the detection of atrazine and atropine (Wu et al., 2008; Hu et al., 2006). Zhou et al. fabricated the imprinted IOPC for sensing CAP (Zhou et al., 2012). However, formation of high-quality IOPC usually takes hours, days, or even months to complete, and the wet etching of the crystal template may also destroy the hydrogel matrix. Imprinted template molecules must be washed away from the fragile inverse opal, which may further destroy the hydrogel. Moreover, relying on the bulk hydrogel response would prolong the sensing time, which was caused by the slow swelling rate of the bulk hydrogel (Y. Liu et al., 2009; N. Liu et al., 2009). Recently, we have developed an imprinting CPO by the assembly of molecular imprinted microgel particles that could easily identify a small change in Bragg diffraction and rapidly detect 17β-estradiol (Sai et al., 2015). However, the imprinting CPO still needs the bulk hydrogel matrix to stabilize the fragile ordered structure of the microgel particles array, which was time-consuming and complex process. Moreover, the hydrogel matrix may significantly reduce the extent of the volume phase transition of the microgel particles (Chen et al., 2013; Guan and Zhang, 2011).

During the past decade, cross-linking of colloidal array has drawn great attention and some efforts have been made for the stabilization of the highly ordered structure. One way is that the particles in colloidal arrays can be cross-linked making use of a suitable cross-linker (Zhao et al., 2009; Zhang et al., 2012). However, addition of the cross-linker solution may disturb the preformed ordered structure, and the cross-linking reaction usually causes a heterogeneous distribution. Alternatively colloidal particles with functional groups such as vinyl groups, were synthesized and then cross-linked under the special polymerization condition (Chen et al., 2013). Unfortunately this method was time-consuming and difficult to control. A facile method was later developed, in which colloidal particles incorporated with N-hydroxymethylacrylamide (HAM) have cross-linked simultaneously when the spheres assembled into colloidal array taking advantage of the self-cross-linking property of HAM (Chen et al., 2014). Based on this principle, monodisperse spheres composed of a copolymer of poly(N-isopropylacrylamide) (PNIPAM) and HAM were synthesized to build a stable colloidal crystal for sensing temperature (Zhou et al., 2009). Therefore, the introduction of HAM into the imprinting CPO would be a promising way to solidify the ordered structure due to its simple and time-saving characteristics.

Herein, a self-cross-linked imprinting CPO was fabricated using molecular imprinted particles with HAMs (MI-HAM particles) for development of a new photonic CAP sensor without the interference of bulk hydrogel. As shown in Fig. 1, the MI-HAM particles that can be assembled to form the CPO structure and at the same time mutually reacted to form covalent bonds to stabilize the CPO structure. Thus, the obtained self-cross-linked imprinting CPO possessed not only a larger specific surface area with recognition sites for specifically adsorbing CAP molecules, but also the stable high-ordered CPO structure for creating optical signals along with the CAP recognition process. Meanwhile, the developed sensor was employed to detect CAP in real samples. As far as we concerned, there has been few reports on the sensor based on the self-cross-linked imprinting CPO for the detection of CAP or other relevant veterinary drug residues.

The schematic diagram of the novel photonic sensor system.
Figure 1
The schematic diagram of the novel photonic sensor system.

2

2 Materials and methods

2.1

2.1 Chemical and reagents

CAP, chloramphenicol succinate (CAP succinate), penicillin, thiamphenicol, and methyl methacrylate (MMA) were purchased from Aladdin (Shanghai, China). Potassium peroxydisulfate (KPS), methanol, acetic acid, HAM, sulfuric acid and other chemicals were supplied from Tianjin Regent Corp. (Tianjin, China). MMA was treated with activated carbon for 24 h prior to use. KPS was recrystallized using deionized water prior to use. The deionized water used throughout the study was passed through ion-exchange columns. Microscope slides (7 cm × 3 cm × 0.12 cm) were purchased from Haimen Condor Experimental Equipment Factory (Haimen, China). Before use, the slides were immersed in a H2SO4-H2O2 mixture (7:3, V/V) for 12 h, followed by rinsing with deionized water in an ultrasonic bath for 3 times. All solvents and chemicals were of reagent quality and were used without further purification.

2.2

2.2 Instrumentation

As shown in Fig. 1, the schematic diagram of the photonic sensor system basically consists of a Y-shape fiber optical reflection probe (R400-7, Ocean Optics, Dunedin, FL, USA), high resolution fiber-optic spectrometer (HR2000, Ocean Optics, Dunedin, FL, USA), a tungsten halogen light source (HL2000, Ocean Optics, Dunedin, FL, USA), a U-shape brown glass dish and a computer. The surface, the shape and the size of self-cross-linked imprinting CPO were studied using the Thermo-4800 high-resolution field emission scanning electron microscopy (SEM).

2.3

2.3 Preparation of the self-cross-linked imprinting CPO

In a 50 mL glass flask, the CAP (65 mg) and HAM (0.05 mg) were dissolved in MMA (3 mL) and then were stored for 12 h at room temperature (RT) for sufficient complexation. The mixture and KPS (60 mg) were poured into 100 mL flask with a reflux condenser, a teflon stirrer powered by a mechanical stirrer, a temperature sensor and a nitrogen inlet. After degassing and nitrogen purging for about 10 min to remove oxygen, the flask was allowed to polymerization at 80 °C with constant stirring rate of 300 rpm and the presence of nitrogen gas for 45 min. These MI-HAM particles were fully dispersed in deionized water and then were injected into a clean staining jar. After complete evaporation of deionized water, a CPO structure was formed and the self-crosslink reaction between neighboring MI-HAM particles was carried out at the same time. The self-cross-linked imprinting CPO film was finally obtained by the removal of the template molecules CAP with a mixture of acetic acid and methanol (15:1, V/V) until no CAP molecules were detected by a UV-vis spectrophotometer. At the same time, a self-cross-linked non-imprinting CPO was also fabricated with the same manner but under conditions of the absence of CAP. The self-cross-linked imprinting CPO and the self-cross-linked non-imprinting CPO were respectively equilibrated in deionized water before recording reflection measurements.

2.4

2.4 The photonic CAP sensor analytical performance

Technical details on the photonic sensor system used this work have been shown in Fig. 1. The prepared self-cross-linked imprinting CPO was fixed into a piece of U-shape brown glass dish, which served as a reaction cell under the optical fiber probe that linking with a tungsten halogen light source and high resolution fiber-optic spectrometer. The sensitivity of the sensor was examined by adding different concentrations of CAP in methanol solutions. After detection, the used self-cross-linked imprinting CPO film was rinsed with a mixture of acetic acid and methanol (15:1, V/V) solution for recovery. Analogues of CAP including CAP succinate, thiamphenicol and penicillin at different concentrations in methanol solution were detected respectively for measuring the selectivity and specificity. A series of tests on the sensor regarding repeatability and reproducibility were undertaken at the same conditions.

The data analysis was performed by normalizing the changes of Bragg diffraction intensity with the following Eq. (1):

(1)
Δ I = ( h 0 - b 0 ) - ( h x - b x ) where ΔI is the change of the peak intensity of the response, h0 and b0 are the reflection peak height of the spectrum and baseline respectively, and hx and bx represent the reflection peak height values and the baseline values, respectively, after adding CAP solution.

2.5

2.5 Real sample preparation for analysis

Drinking water sample was obtained from the Haihe River in Tianjin. A Millipore filter (0.45 μm) was used to filter the water sample, then CAP standard (20 ng mL−1, 60 ng mL−1 and 180 ng mL−1) was spiked for analysis.

3

3 Results and discussion

3.1

3.1 Preparation of self-cross-linked imprinting CPO films

The self-cross-linked imprinting CPO films were prepared with MI-HAM particles by a self-assembly approach. Firstly, the MI-HAM particles were synthesized by emulsion-free polymerization. The size of the particles can be adjusted in the range of 180–250 nm by changing the polymerization conditions. Concretely, larger sized particles were synthesized by using a more amount of MMA, a less amount of KPS, a slower rotation speed or lower temperatures. In contrary, smaller size particles were obtained using a smaller MMA, larger KPS, higher temperatures or faster rotation speed. In our work, monodisperse particles with an average diameter of 210 nm were used to form CPO structure by a vertical deposition method on glass substrates. During the formation of the CPO structure, constant temperature, humidity and quiet environment were necessary in order to produce a highly ordered CPO structure avoiding the irregular deposition layer conformation. In addition, it should be noted that the CPO structure can be cross-linked by itself. In the process of CPO structure formation, the MI-HAM particles were gradually close to each other by the self-assembly and reacted each other to form covalent bonds to stabilize the CPO structure based on the self-crosslinking property of HAM with the evaporation of water from the particles dispersion. After removal of CAP templates with weak acid solution, the stable self-cross-linked imprinting CPO with numerous recognition sites was fabricated. Generally, the fabrication of molecular imprinted PCs needs considerable time. For imprinted IOPC materials (Zhou et al., 2012; Hu et al., 2006; Wu et al., 2008), it usually takes hours, days, or even months to prepare the material. For our previous material (Sai et al., 2015), the extra process of hydrogel matrix synthesis was required spending tens of minutes. Therefore, the preparation of the self-cross-linked imprinting CPO was an easy and time-saving process as the material had self-assembled and self-crosslinking functions.

Fig. 2 shows SEM images of the self-cross-linked imprinting CPO. The highly ordered monodispersity and the CPO arrangement were clearly observed in Fig. 2A. The monodispersity offered the self-assembly and the production of face-centered cubic (FCC) ordered layers of particles. In addition, there were linkages between neighboring particles for the stabilization of the CPO structure. Fig. 2B demonstrated a random particle touching another six in one layer, evidenced by a highly 3D ordered with a hexagonal symmetry of the imprinting CPO. The self-cross-linked imprinting CPO were arranged over the entire surface with the (1 1 1) plane of the FCC lattice, parallel to the substrate, making it easier for the target molecules to pass in and out. Therefore, the target molecules can be washed off and adsorbed easily. As a result, these special structure characteristics enabled the material not only to immediately create optical signals due to the Bragg diffraction effects, but also to rapidly and sensitively respond to target analytes due to their large integrated area and the easy accessibility of drugs into the recognition sites within the self-cross-linked imprinting CPO.

Morphology of the self-cross-linked imprinting CPO: (A) SEM image was taken at 50 000× and (B) fractured surface showing the FCC array of particles 100 000×.
Figure 2
Morphology of the self-cross-linked imprinting CPO: (A) SEM image was taken at 50 000× and (B) fractured surface showing the FCC array of particles 100 000×.

3.2

3.2 The photonic sensor analytical performance for the determination of CAP

When a series of concentrations of CAP were injected into the senor, the optical signal changes are shown in Fig. 3. As shown in Fig. 3, the diffraction intensity decreased by 1.718 a.u upon exposure to 2 ng mL−1 of CAP. It was found that the sensor was very sensitive to CAP molecules. With an increase of the CAP concentration, the diffraction intensity decreased gradually, and then reached the plateau value around 512 ng mL−1 of CAP due to saturation of accessible imprinting recognition sites. Relationship between CAP concentration and ΔI (the reducing value of the diffraction intensity) was calculated. It was learned that the photonic sensor exhibited an great linear relationship between CAP concentration and ΔI with R value of 0.99122, which was better than our previous work (Sai et al., 2015). This phenomenon may be due to the avoidance of the bulk hydrogel interference in this study. As a result, this sensor can realize quantitative detection of CAP with the help of spectrometer, which establishes a good foundation in order to detect CAP in real samples.

The typical responses of the photonic sensor using the self-cross-linked imprinting CPO and the regression curve of the photonic sensor using the self-cross-linked imprinting CPO.
Figure 3
The typical responses of the photonic sensor using the self-cross-linked imprinting CPO and the regression curve of the photonic sensor using the self-cross-linked imprinting CPO.

3.3

3.3 Possible reaction mechanisms of the photonic sensor

To further clarify the molecular recognition property of the photonic sensor, the self-cross-linked non-imprinting CPO was used as a recognition element instead of the self-cross-linked imprinting CPO. As shown in Fig. 4, the diffraction intensity responded slightly and changed with irregular fluctuation along with the change of CAP concentration, which was greatly different from the response event of the self-cross-linked imprinting CPO in Fig. 3. This may be explained by the absence of the CAP imprinting sites in the self-cross-linked non-imprinting CPO. Therefore, the sensing properties of the photonic sensor were due to the numerous recognition sites derived from CAP imprinting and obeyed the recognition mechanism of molecular imprinted technology. On the other hand, when applying the bulk imprinting polymer without CPO structure as a recognition element, we found that the diffraction peak disappeared, leading to an ill-defined optical signal (not shown), which may be caused by the absence of Bragg diffraction effects. Thus, just using the self-cross-linked imprinting CPO would be able to play a role in the sensor. When the CAP solution was absorbed on the self-cross-linked imprinting CPO, the recognition event with high affinity can occur and cause reduction of diffraction intensity subsequently in Fig. 3. The phenomenon would be illustrated by the following reasons. Firstly, CAP molecules entering into the self-cross-linked imprinting CPO can form a multitude of simultaneous hydrogen bonds, electrostatic attraction and associated weak interaction between the internal of imprinting CPO and CAP based on the molecular imprinting recognition. These bonds formation made the colloidal particles of the CPO swell. Thus, with the increase of CAP concentration, the size of particles increased, and resulted in an increase in the inter-planar spacing followed by the reflection intensity reducing. The results of our analysis were consistent with those of some reports (Hall et al., 2005; Guo et al., 2012). Moreover, the increase in the effective refractive index can be one of the factors causing the decrease of the Bragg diffraction intensity. The response to CAP adsorption can be resulted in a decrease in the average refractive index (na), causing a decrease in diffraction peak intensity. The effective refractive index na of the CPO is calculated as follows:

(2)
n a = n particle 2 f particle + n water 2 1 - f particle 1 / 2
The typical responses of the photonic sensor using the self-cross-linked non-imprinting CPO versus different concentration of CAP.
Figure 4
The typical responses of the photonic sensor using the self-cross-linked non-imprinting CPO versus different concentration of CAP.

In this case, nparticle = 1.492 and nH2O = 1.333 (Waterhouse and Wat, 2007). Therefore, the refractive index ratios of the self-cross-linked imprinting CPO (nparticle/nH2O = 1.119) were all less than the value of 2.9, which is required for the realization of a full gap. Therefore, they exhibit only pseudo photonic band gaps. The theoretical requirements to achieve a complete band gap in a CPO strcture included a refractive index comparatively higher than 2.9. In short, the swelling of the particles caused a decrease in the refractive index of the spheres (nswell particle < nparticle), so nparticle/nH2O < 1.119 became small. Therefore, the molecular recognition event based on molecular imprinting would affect some of structural characteristics of CPO, which finally evolved into optical signal changes.

3.4

3.4 Selectivity study

The selectivity study of the photonic sensor was investigated by using two structurally similar antibiotics (CAP succinate as well as thiamphenicol), and one structurally unrelated antibiotic (penicillin). Compared to the results in Fig. 3, CAP succinate and thiamphenicol induced slight optical changes of diffractive intensity (Fig. 5). This could be easily explained by their close homologous to CAP and having the same functional group in the specific position, thus forming a similar recognition behavior with CAP as shown in Fig. 6. The selectivity of CAP-imprinted photonic sensors was investigated by several groups previously, and similar results were also observed. For example, Kara et al studied selectivity of a surface plasmon resonance nanosensor using molecular imprinted nanoparticles and found that thiamphenicol could bind the sensor with constants 8.86 for CAP/ thiamphenicol (Kara et al., 2013). On the other hand, there was a low affinity of the structurally unrelated penicillin, causing almost no perceptible optical signal changes of the sensor. Furthermore, it was learned that the average cross selectivity of the sensor for penicillin turned out to be 1.1%, even that for CAP succinate and thiamphenicol that have similar structure to CAP were found to be less than 13%. Therefore, it was suggested that the sensor possessed highly specific and sensitive recognition ability for CAP.

Response comparison of the photonic sensor versus different concentration of CAP, CAP succinate, penicillin as well as thiamphenicol.
Figure 5
Response comparison of the photonic sensor versus different concentration of CAP, CAP succinate, penicillin as well as thiamphenicol.
Structural formulae of CAP and other antibiotics used in this study.
Figure 6
Structural formulae of CAP and other antibiotics used in this study.

3.5

3.5 Response characteristics and reproducibility

The sensing characteristics of the photonic sensor were investigated by the adding CAP solution (256 ng mL−1) for 0–15 min. As shown in Fig. 7A, the sensing time of the sensor reached 7 min and represented a dynamic and continuous response process. This rapid response of our sensor would be caused by the following reasons. Firstly, the small microgel MI-HAM particles can easily identify small change in Bragg diffraction compared with the bulk hydrogel response. In addition, its homogeneous layers and the high surface-to-volume ratio of the self-cross-linked imprinting CPO made the CAP molecules diffuse into the material and occupy the binding sites easily. In addition, the established photonic sensors to determine CAP usually require a longer detection time (Estevez et al., 2012; Ciminellin et al., 2013). For the IOPC bulk hydrogels for CAP (Zhou et al., 2012), the response achieved stability within 8 min. For a surface plasmon resonance sensor (Yang et al., 2016), it usually takes tens of minutes to separate the analyte before determination. For the high-throughput suspension arrays senor (Y. Liu et al., 2009; N. Liu et al., 2009), it generally consumes more than 30 min to get a result.

(A) Response time and (B) recoverability of the photonic sensor.
Figure 7
(A) Response time and (B) recoverability of the photonic sensor.

As the self-cross-linked imprinting CPO was of a highly cross-linked polymeric nature, the corresponding sensors also showed good physical stability and chemical inertness. The recoverability of the sensor was studied by an elution and rebinding method. From Fig. 7B, it can be observed obviously that the sensor possessed a good recoverability in 6 cycles and, the relative standard deviation (RSD) was just within 4.9%. Therefore, the novel photonic sensor can be used repeatedly several times and still maintain its responsive property.

3.6

3.6 Application

The developed sensor was used to analyze CAP in drinking water samples. As shown in Fig. 8, there were obvious diffraction intensity decreases according to different CAP spiked concentrations. Therefore, the application of the sensor platform made the detection of significant amounts of CAP residuals in liquid sample possible.

Diffraction response of the sensor in the Cm spiked drinking water.
Figure 8
Diffraction response of the sensor in the Cm spiked drinking water.

4

4 Conclusion

A novel photonic sensor by using the self-cross-linked imprinting CPO as a recognition element was described. The constructed sensory system is characterized by (a) self-cross linking to get rid of the interference from the bulk hydrogel; (b) low cost, easy construction and simple operation; and (c) rapid, sensitive and selective response. Moreover, the sensor was successfully applied in the real samples for sensing CAP. Therefore, the described assay not only provided an attractive alternative to create optical diffraction-based chemical or biological sensors, but also expanded the applications of CPO films in other areas such as drug separation, surface patterning and clinical assays. Further research should be focused on the improvement of the sensing sensitivity and selectivity of the sensor for other solid samples testing, such as seafood, livestock and poultry meat.

Acknowledgments

The authors gratefully acknowledge the financial supports by National Natural Science Foundation of China (Grant 81302430), China Postdoctoral Science Foundation (Grant 2014M560192), and Tianjin City High School Science & Technology Fund Planning Project (Grant 20110143).

References

  1. , , , , , . Design and fabrication of an aptasensor for chloramphenicol based on energy transfer of CdTe quantum dots to graphene oxide sheet. Mater. Sci. Eng., C. 2015;48:611-619.
    [Google Scholar]
  2. , , , , , , . Charge stabilized crystalline colloidal arrays as templates for fabrication of non-close-packed inverted photonic crystals. J. Colloid Interface Sci.. 2010;344:298-307.
    [Google Scholar]
  3. , , , , , , , , . Multiplexed specific label-free detection of NCI-H358 lung cancer cell line lysates with silicon based photonic crystal microcavity biosensors. Biosens. Bioelectron.. 2013;43:50-55.
    [Google Scholar]
  4. , , , , . Polymerized microgel colloidal crystals: photonic hydrogels with tunable band gaps and fast response rates. Angew. Chem. Int. Ed.. 2013;52:9961-9965.
    [Google Scholar]
  5. , , , , , . Multifunctional electrospun nanofibers prepared from poly((N-isopropylacrylamide)-co-(N-hydroxymethylacrylamide)) and their blends with 1,2-diaminoanthraquinone for NO gas detection. Macromol. Chem. Phys.. 2014;215(3):286-294.
    [Google Scholar]
  6. , , , , , . Label-free optical resonant sensors for biochemical applications. Prog. Quantum Electron.. 2013;37:51-107.
    [Google Scholar]
  7. , , , , , , , . Color changing photonic crystals detect blast exposure. Neuro Image. 2011;54:37-44.
    [Google Scholar]
  8. , , , . Biomimetic piezoelectric quartz crystal sensor with chloramphenicol-imprinted polymer sensing layer. Talanta. 2015;144:1260-1265.
    [Google Scholar]
  9. , , , . Integrated optical devices for lab-on-a-chip biosensing applications. Laser Photonics Rev.. 2012;6:463-487.
    [Google Scholar]
  10. , , , , , , . Flow injection chemiluminescence sensor using molecularly imprinted polymers as recognition element for determination of maleic hydrazide. Biosens. Bioelectron.. 2009;24:2323-2327.
    [Google Scholar]
  11. , , , , , . A photonic crystal based sensing scheme for acetylcholine and acetylcholinesterase inhibitors. J. Mater. Chem. B. 2015;3:2089-2095.
    [Google Scholar]
  12. , , , . An optical sensor for the determination of digoxin in serum samples based on a molecularly imprinted polymer membrane. Anal. Chim. Acta. 2009;638:209-212.
    [Google Scholar]
  13. , , . PNIPAM microgels for biomedical applications: from dispersed particles to 3D assemblies. Soft Matter. 2011;7:6375-6384.
    [Google Scholar]
  14. , , , , , , , . Detection of bisphenol A using an opal photonic crystal sensor. Sens. Actuators B – Chem.. 2012;166:3925-4005.
    [Google Scholar]
  15. , , , , . Non-covalent imprinting of phosphorous esters. Anal. Chim. Acta. 2005;538:9-14.
    [Google Scholar]
  16. , , , , , , . Monitoring the presence of chloramphenicol and nitrofuran metabolites in cultured prawn, shrimp and feed in the Southwest coastal region of Bangladesh. Egypt. J. Aquat. Res.. 2013;39:51-58.
    [Google Scholar]
  17. , , , , , , , . A novel opal closest-packing photonic crystal for naked-eye glucose detection. Small. 2014;10:1308-1313.
    [Google Scholar]
  18. , , , , , . Imprinted photonic polymers for chiral recognition. Angew. Chem. Int. Ed.. 2006;45:8145-8148.
    [Google Scholar]
  19. , , , , , , , . Ultrasensitive specific stimulant assay based on molecularly imprinted photonic hydrogels. Adv. Funct. Mater.. 2007;18:575-583.
    [Google Scholar]
  20. , , , , , , . Screening and confirmation of chloramphenicol in shrimp tissue using ELISA in combination with GC–MS2 and LC–MS2. Anal. Chim. Acta. 2003;483:153-163.
    [Google Scholar]
  21. , , , , . Combining molecular imprinted nanoparticles with surface plasmon resonance nanosensor for chloramphenicol detection in honey. J. Appl. Polym. Sci.. 2013;129:2273-2279.
    [Google Scholar]
  22. , , . Electrochemical determination of chloramphenicol on glassy carbon electrode modified with multi-walled carbon nanotube–cetyltrimethylammonium bromide–poly(diphenylamine) J. Electroanal. Chem.. 2014;733:39-46.
    [Google Scholar]
  23. , , , . New polymerized crystalline colloidal array for glucose sensing. Chem. Commun. 2009:1867-1869.
    [Google Scholar]
  24. , , , , , , , . Development of a high-throughput suspension microarray technology for detection of three kinds of veterinary drug residues: chloramphenicol, clenbuterol and 17-beta-estradiol. Zhonghua Yu Fang Yi Xue Za Zhi. 2009;43:482-488.
    [Google Scholar]
  25. , , , , , . Monodisperse, high refractive index, highly charged ZnS colloids self assemble into crystalline colloidal arrays. J. Colloid Interface Sci.. 2010;345:131-137.
    [Google Scholar]
  26. , , , . Electrochemical sensor for bovine hemoglobin based on a novel graphene-molecular imprinted polymers composite as recognition element. Sens. Actuators B: Chem.. 2014;203:782-789.
    [Google Scholar]
  27. , , , , , . Fluorescent aptasensor for chloramphenicol detection using DIL-encapsulated liposome as nanotracer. Biosens. Bioelectron.. 2016;81:454-459.
    [Google Scholar]
  28. , , , . The sensitivity evanescent-field gas sensor based on modified photonic crystal fiber for gas condensate and air pollution monitoring. Optik-Int. J. Light Electron Opt.. 2014;125:596-600.
    [Google Scholar]
  29. , , , , , . Gold nanocatalyst-based immunosensing strategy accompanying catalytic reduction of 4-nitrophenol for sensitive monitoring of chloramphenicol residue. Anal. Chim. Acta. 2014;830:42-48.
    [Google Scholar]
  30. , , , , , , , , , , . A sensitive immunoassay based on direct hapten coated format and biotin–streptavidin system for the detection of chloramphenicol. Talanta. 2010;82:1113-1121.
    [Google Scholar]
  31. , , , , , . Molecular imprinted opal closest-packing photonic crystals for the detection of trace 17β-estradiol in aqueous solution. Talanta. 2015;144:157-162.
    [Google Scholar]
  32. , , . Screening, determination and confirmation of chloramphenicol in seafood, meat and honey using ELISA, HPLC–UVD, GC–ECD, GC–MS–EI–SIM and GCMS–NCI–SIM methods. Anal. Chim. Acta. 2005;535:33-41.
    [Google Scholar]
  33. , , . Molecularly imprinted polymer based enantioselective sensing devices: a review. Anal. Chim. Acta. 2015;853:1-18.
    [Google Scholar]
  34. , , , , . Synthesis of a novel polyurethane-based-magnetic imprinted polymer for the selective optical detection of 1-naphthylamine in drinking water. Biosens. Bioelectron.. 2011;26:4520-4525.
    [Google Scholar]
  35. , , , , , , , , . Responsive photonic crystal for the sensing of environmental pollutants. Trends Environ. Anal. Chem.. 2014;3–4:1-6.
    [Google Scholar]
  36. , , , . Polymerized crystalline colloidal array sensing of high glucose concentrations. Anal. Chem.. 2009;81:4978-4986.
    [Google Scholar]
  37. , , . Opal and inverse opal photonic crystals: fabrication and characterization. Polyhedron. 2007;26:356-368.
    [Google Scholar]
  38. , , , , , . Label-free colorimetric detection of trace atrazine in aqueous solution by using molecularly imprinted photonic polymers. Chem. – Eur. J.. 2008;14:11358-11368.
    [Google Scholar]
  39. , , , , , , , . Aptamer-based fluorescence biosensor for chloramphenicol determination using upconversion nanoparticles. Food Control. 2015;50:597-604.
    [Google Scholar]
  40. , , , , , , . A simple and sensitive electrochemical aptasensor for determination of Chloramphenicol in honey based on target-induced strand release. J. Electroanal. Chem.. 2012;687:89-94.
    [Google Scholar]
  41. , , , , , , , , , , . Immunomagnetic reduction assay on chloramphenicol extracted from shrimp. Food Chem.. 2012;131:1021-1025.
    [Google Scholar]
  42. , , , , . Preliminary study on handwashing and disinfection procedures of food processing personnel. Journal of Food Safety and Quality. 2015;6:3787-3790.
    [Google Scholar]
  43. , , , , , , . Electrocatalytic determination of chloramphenicol based on molybdenum disulfide nanosheets and self-doped polyaniline. Talanta. 2015;131:619-623.
    [Google Scholar]
  44. , , , . Novel biosensor based on competitive SERS immunoassay and magnetic separation for accurate and sensitive detection of chloramphenicol. Biosens. Bioelectron.. 2016;80:373-377.
    [Google Scholar]
  45. , , , , , , . Urea sensing materials via solidified crystalline colloidal arrays. Sens. Actuators B. 2002;81:273-276.
    [Google Scholar]
  46. , , , , . Assembling of gold nanorods on P(NIPAM–AAPBA) microgels: a large shift in the plasmon band and colorimetric glucose sensing. RSC Adv.. 2012;2:4768-4776.
    [Google Scholar]
  47. , , , . Specific and ultrasensitive ciprofloxacin detection by responsive photonic crystal sensor. J. Hazard. Mater.. 2014;280:46-54.
    [Google Scholar]
  48. , , , , , , . Multiplex label-free detection of biomolecules with an imprinted suspension array. Angew. Chem. Int. Ed.. 2009;48:7350-7352.
    [Google Scholar]
  49. , , , , . The formation of crystalline hydrogel films by self-crosslinking microgels. Soft Matter. 2009;5:820-826.
    [Google Scholar]
  50. , , , , , , , , , , , . Molecularly imprinted photonic polymer as an optical sensor to detect chloramphenicol. Analyst. 2012;137:4469-4474.
    [Google Scholar]

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